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0. Harty > Oncology > Flashcards

Oncology Flashcards

1
Q

Approach to benign aggressive lesion

A
  1. Comprehensive history
  2. Comprehensive physical
  3. Radiographs
  • Look for neocortex
  • Usually epiphyseal/metaphyseal
  • Usually lytic
  • DDx
    • ABC
      • (Telangiectactic osteosarcoma) Include in DDx for ABC
    • GCT
    • CMF
    • Osteoblastoma
    • Chondroblastoma
      • If epiphyseal, DDx includes clear cell chondrosarcoma
  1. MRI
  2. CXR
  • Lung mets
    • GCT
    • Chondroblastoma
  1. Biopsy
  2. Treatment
  • Generally, extended intralesional curettage and bone grafting
    • ***NOTE:
      • Augments include high speed burr, phenol, liquid nitrogen
  • En bloc resection and reconstruction
    • If eroded through cortex
  1. Followup
  • History and physical examination
  • GCT - limb and chest radiographs q3m x 2y, then q6m to 5y, then yearly to 10y
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2
Q

Approach to Osteosarcoma

A
  1. Comprehensive history
  2. Comprehensive physical
  3. Radiographs
  • Ddx
    • Osteosarcoma
    • Ewing’s
    • Infection
    • EG
    • Hematologic malignancy
  1. Full length MRI
  2. Bone scan
  3. CT chest
  4. Biopsy
    * CT or US guided core needle biopsy OR open
  5. Consult medical oncology
  • Prior to chemo:
    • BW – LDH, ALP, CBC, LFTs, urea/Cr
    • Echo
    • Audiogram
      1. Neoadjuvant chemotherapy
  • Doxorubicin, methotrexate, cisplatin
  • 10 week course preop

10.Re-stage

  • Radiographs
  • Full length MRI
  • Bone scan
  • CT chest
  1. Surgery
  • Limb sparing surgery with wide margin resection and reconstruction
    • Tumor prosthesis
    • Intercalary allograft/autograft
    • Rotationplasty
    • APC
  • Amputation
    • Pathological fracture
    • Encasing neurovascular structures
    • Poor response to chemo
      1. Adjuvant chemotherapy
  • Doxorubicin, methotrexate, cisplatin
  • ?6 months
  1. Followup (Surveillance)
  • History, physical, CXR, extremity x-ray
  • Every 3 months for 2 years, 6 months until year 5, then annually until year 10
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3
Q

Approach to Ewing’s Sarcoma

A
  1. Comprehensive history
  2. Comprehensive physical
  3. Radiographs
  • Ddx
    • Osteosarcoma
    • Infection
    • EG
    • Hematologic malignancy
  1. Full length MRI
  2. Bone scan
  3. CT chest
  4. *Bone marrow biopsy
  5. Biopsy
    * CT or US guided core needle biopsy OR open
  6. Consult medical oncology
  • Prior to chemo:
    • BW – LDH, ALP, CBC, LFTs, urea/Cr
    • Echo
    • Audiogram
  1. Neoadjuvant chemotherapy
  • *Doxorubicin, Vincristine, Cyclophosphamide, ifosfamide and etoposide
  • ~10 week course (4-8 cycles)
  1. Re-stage
  • Radiographs
  • Full length MRI
  • Bone scan
  • CT chest
  1. Surgery
  • Limb sparing surgery with wide margin resection and reconstruction
    • Tumor prosthesis
    • Intercalary allograft/autograft
    • Rotationplasty,
    • APC
  • Amputation
    • Pathological fracture
    • Encasing neurovascular structures
    • Poor response to chemo
    • Lesions of foot or ankle
      1. Adjuvant chemotherapy
  • ?6 months
    14. *Radiation if inadequate surgical margins OR surgery would be too morbid or unresectable (pelvis, spine, etc)
    15. Followup (Surveillance)
  • History, physical, CXR, extremity x-ray
  • Every 3 months for 2 years, 6 months until year 5, then annually until year 10
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4
Q

Approach to Soft Tissue Sarcoma

A
  1. Comprehensive history
  2. Comprehensive physical
  3. (Radiographs)
  4. MRI
  5. CXR
  6. CT chest
    * If myxoid liposarcoma = CT chest/abdo/pelvis
  7. Biopsy
    * US guided core needle biopsy
  8. Consult radiation oncology
  • Pre-operative
    • Lower dose (~50Gy) over ~5 weeks with surgery ~4 weeks after completion
    • Higher wound complication
  • Post-operative
    • Higher dose (~66Gy)
    • More fibrosis and joint contractures
  1. Surgery
    * Wide surgical resection (>1cm margins)
  2. Followup
  • History, physical, CXR
  • Every 3 months for 1 year, q6months for 1 year, then annually for 10 years
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5
Q

Approach to isolated destructive bone lesion in an adult

A
  1. Comprehensive history
  2. Comprehensive physical
  3. Radiographs
  • Ddx
    • Mets
    • Myeloma
    • Lymphoma
    • Primary bone tumor
    • Infection
  1. Bloodwork
  • CBC, Lytes, extended lytes, Cr, urea
  • ALP, LDH, PTH, LFTs
  • SPEP
  • ESR/CRP
  • PSA
  1. Urine
  • Urinalysis
  • UPEP
  1. Imaging
  • Full length radiographs
  • Bone scan
  • CT chest/abdo/pelvis
  • CT/MRI of lesion (full length bone involved)
  • Optional:
    • Skeletal survey
    • Thyroid US
    • Mammography
      1. Biopsy
  • CT/US core needle biopsy OR open
    8. Treatment of confirmed metastatic bone lesion
  • +/- preoperative IR embolization for RCC/thyroid mets
  • Construct providing immediate stability and protection of entire bone
    • IM nail vs. plate
    • Possible tumor prosthesis for joint involvement
    • +/- cement augmentation for stability
  • Local control
    • Surgical curettage/resection of bone segment
    • Consult radiation oncology for postoperative radiation
  • Bisphosphonate
    9. Followup
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6
Q

Radiographic assessment of a bone lesion should assess/describe the following factors?

A
  1. Type of radiograph (eg. AP/lateral right knee)
  2. Skeletally immature or mature
  3. Site of the lesion
  • Epiphysis, metaphysis, diaphysis
  • Central, eccentric, cortical, periosteal
  1. Geographic vs. nongeographic border
    * Nongeographic = moth-eaten or permeative
  2. Matrix
  • Osteoid
  • Chondroid (stippled, rings and arcs, flocculent)
  • Myxoid
  • Fibrous
  1. Cortex involvement
  • Endosteal scalloping
  • Thinning
  • Expanded
  • Neocortex
  • Disrupted
  1. Periosteal reaction
  • None
  • Continuous (cortical thickening)
  • Sunburst (hair-on-end)
  • Onion skin
  • Codman’s triangle
  1. Soft tissue mass
  2. Size and number of lesions
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7
Q

Pediatric aggressive malignant lesions

A
  1. Ewing’s sarcoma
  2. Osteosarcoma
  3. Infection
  4. Eosinophilic granuloma
  5. Hematologic malignancy
  6. Metastatic tumor (Wilm’s, Neuroblastoma)
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8
Q

Benign Aggressive bone tumour

A
  • ABC
    • (Telangiectactic osteosarcoma) Include in DDx for ABC
  • GCT
  • CMF
  • Osteoblastoma
  • Chondroblastoma
    • If epiphyseal, DDx includes clear cell chondrosarcoma
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9
Q

Lesions in the posterior elements of the spine

A
  1. Osteoblastoma
  2. Osteoid osteoma
  3. Osteochondroma
  4. ABC
  5. Metastasis
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10
Q

Lesions in the epiphysis

A
  1. Chondroblastoma
  2. Clear cell chondrosarcoma
  3. Geode
  4. Infection
  5. EG
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11
Q

Anterior tibial cortical thickening differential?

A
  1. Stress fracture
  2. Osteoid osteoma
  3. Infection
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12
Q

What are the ‘small round blue cell’ tumours?

A

LEARN

  • Lymphoma
  • Ewings
  • Acute leukemia
  • Rhabdomyosarcoma
  • Neuroblastoma
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13
Q

What types of surgical margins can be considered?

[AAOS comprehensive review 2, 2014, pg. 487]

A
  1. Intralesional
  2. Marginal
  3. Wide
  4. Radical
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14
Q

Tumors treated with wide resection alone?

[AAOS comprehensive review 2, 2014]

A
  1. Chondrosarcoma
  2. Adamantinoma
  3. Parosteal osteosarcoma
  4. Chordoma
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15
Q

What are the most common bone tumours?

[Orthobullets][AAOS comprehensive review 2, 2014]

A
  1. Most common malignancy of bone = metastasis
  2. Most common malignancy of bone in children = intramedullary osteosarcoma
  3. Most common primary bone malignancy = myeloma
  4. Most common bone sarcoma = intramedullary osteosarcoma
  5. Most common soft tissue sarcoma of hand/wrist = epitheliod sarcoma
  6. Most common soft tissue sarcoma of foot = synovial sarcoma
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16
Q

What are complications of radiation treatment in skeletally immature patients?

A
  • Joint contractures
  • Fibrosis
  • Growth arrest (LLD)
  • Fracture
  • Secondary malignancy
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17
Q

What are the syndromes associated with the following tumors?

A
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18
Q

What are the biopsy principles?

A
  1. Incision in line with planned resection incision
    * Longitudinal in extremities
  2. Go through muscle compartments (not around)
  3. Meticulous hemostasis
  • Prevents hematoma and tumor spread
  • Drain if needed, avoid if possible, place distal in line with incision
  1. Do not undermine or raise flaps
  2. Avoid neurovascular structures and joints
  3. Biopsy soft tissue mass if present
    * If not, enter bone through weakest cortex, drill oval/round window if needed
  4. Send frozen section for lesional tissue
  • Should also always send fresh tissue
    • Lymphoma of bone needs fresh tissue for flow cytometry
  • Consider sending for C&S if infection on differential
  1. Water tight closure

***NOTE: if biopsy bleeds do not extend incision

  • Manage bleed with gel foam, packing, cement or drain
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19
Q

What is the differential for an isolated destructive bone lesion in an adult?

A
  1. Metastasis
  2. Multiple myeloma
  3. Lymphoma
  4. Primary bone tumours
  • Chondrosarcoma
  • Malignant fibrous histiocytoma
  • Chordoma
  • Osteosarcoma
  1. Benign lesions
    * Giant cell tumour
  2. Non-neoplastic
  • HyperPTH
  • Osteomyelitis
  • Gorham vanishing bone disease
    • Progressive bone loss (osteolysis) and the overgrowth (proliferation) of lymphatic vessels
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20
Q

Workup for unknown primary?

A

Undertaken when an adult presents with a destructive bone lesion without a history of cancer

  • Must differentiate between metastatic disease and primary bone tumour
    1. Bloodwork
  • CBC, Lytes, extended lytes, Cr, urea
  • ALP, LDH, PTH, LFTs
  • SPEP
  • ESR/CRP
  • PSA
  1. Urine
  • Urinalysis
  • UPEP
  1. Imaging
  • Full length radiographs
  • Bone scan
  • CT chest/abdo/pelvis
  • CT/MRI of lesion (full length bone involved)
  • Optional:
    • Skeletal survey
    • Thyroid US
    • Mammography
      1. Biopsy
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21
Q

What primary tumors commonly metastasize to bone?

A

BLT KP

  • Breast
  • Lung
  • Thyroid
  • Kidney
  • Prostate
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22
Q

Consider preoperative (pre-open biopsy) embolization for which bone lesions?

A
  1. Renal cell carcinoma mets
  2. Thyroid carcinoma mets
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23
Q

What malignant lesions are commonly cold on bone scan?

A
  1. Multiple myeloma
  2. Thyroid mets
  3. Renal mets
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24
Q

What metastatic cancers are sensitive to radiation and which are resistant?

A
  1. Radiosensitive
  • Lung
  • Breast
  • Prostate
  • Lymphoma
  • Myeloma
  1. Radioresistant (think cold bone scan)
  • RCC
  • Thyroid carcinoma
  • Melanoma
  • GI adenocarcinoma
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25
Q

What nonoperative management can benefit lytic destructive lesion in adult?

A

Bisphosphonate

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26
Q

What is Mirel’s Classification/Score?

A
  1. The goal is to predict impending fractures and prophylactically fix in an elective setting
    * Avoids urgent hospitalisation and severe pain associated with pathological fractures and allows for medical optimization to minimize the risk of surgery
  2. Considers
  • Site of lesion (UE, LE, trochanteric region)
  • Nature of lesion (blastic, mixed, lytic)
  • Size of lesion (<1/3, 1/3-2/3, >2/3 of cortex)
  • Pain (mild, moderate, functional)
    3. According to Mirels’ recommendations:
  • Score >8 - prophylactic fixation is indicated
  • Score <8 - lesion can be managed with radiation or drugs
  • Score = 8 - clinical dilemma
    • Probability of fracture is 15% and clinician should use clinical judgement
  1. Sensitivity = 91%, specificity = 35%
    * Specificity of 35% may lead to false positives and unnecessary procedures
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27
Q

What are the benefits of prophylactic fixation of a metastatic bone lesion?

[AAOS comprehensive review 2, 2014, pg. 487]

A
  1. Avoids urgent hospitalization
  2. Decreased perioperative pain
  3. Allows for medical optimization
  4. Technically easier surgery
  5. Shorter OR time
  6. Faster recovery/decreased length of stay
  7. Allows for coordination with medical oncology
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28
Q

What are the surgical goals and options for the management of metastatic bone disease?

[JBJS 2009; 91(6): 1503]

A
  1. Immediate stability, protect the entire bone, reduce pain and increase function
  2. Local tumor control
    * Radiation or local surgical curettage/resection of bone segment
  3. Long bones
  • Closed IM nailing preferred
    • Without cement if minimal bone destruction
    • With cement if significant bone destruction
  • Plates if nonWB bone (eg. humerus) or lesion too proximal or distal for nail
  • Tumour prosthesis if joint involvement
  1. Acetabulum
    * Harrington technique – threaded pins in ilium as rebar support for cemented acetabular component
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29
Q

What is the management of massive bleeding during local tumor control (eg. RCC)?

[CORF]

A
  1. Remove tumor as fast as possible
  2. Be prepared for blood loss – have cement available
  3. Notify anaesthesia
  4. Call for blood products
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30
Q

When can a solitary destructive bony lesion be nailed?

A
  1. Known metastatic malignancy
  2. Frozen section sent at time of surgery confirming ‘carcinoma’
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31
Q

What is the management of hypercalcemia of malignancy?

[Am Fam Physician. 2003 May 1;67(9):1959-1966.]

A
  1. Recognize symptoms
  • “Stones, bones, abdominal moans, and psychic groans”
  • Confusion, malaise, fatigue*
  • Abdominal pain, nausea*
  1. ECG
  2. Hydration
  • Insert Foley
  • Bolus IV normal saline 1-2L, then run freely to achieve urine output of 150-200cc/h
  1. Loop diuretic (eg. Lasix)
    * Start once intravascular volume restored
  2. Medicine consult
  • Bisphosphonate
  • Calcitonin
  • Dialysis
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32
Q

What type of resection is required when a bone sarcoma involves a joint?

A

Extra-articular resection

  • E.g. knee involvement is performed either by en-block resection or resection with preservation of the extensor mechanism (splitting the patella and detaching suprapatellar pouch from quads tendon and fat pad from patellar tendon)
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33
Q

Hemipelvectomy:

What is the difference between an internal vs. external hemipelvectomy?

What 3 structures must be considered when deciding between internal and external hemipelvectomy?

What are flap closure options for hemipelvectomy?

A
  1. Internal vs External
  • Internal – limb-sparing surgery
    • Hemipelvis resected, leg preserved
  • External – hindquarter amputatio
    • Hemipelvis and leg amputated
  1. Important structures
  • Sciatic nerve
  • Femoral neurovascular bundle
  • Hip joint
  • ***General rule = should two of these structures require resection to obtain an adequate margin, then external hemipelvectomy should be performed
    3. Flap closure options:
  • Anterior flap – femoral blood supply
    • Indicated if tumor involves buttock or internal iliac vessels
  • Posterior flap (classic) – internal iliac blood supply
    • Indicated if tumor involves external iliac or femoral vessels
  • Free flap
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34
Q

Osteoid Osteoma

Classification

Age

Presentation

Location

Imaging

Treatment

DDx

A
  1. Classification - Benign active
  2. Age = 5-30
  3. Presentation:
  • Classically night pain relieved with ASA or NSAIDs
  • May cause a painful scoliosis
    • If so lesion located at the centre of the concavity of the curve
  1. Location:
    * Most common = proximal femur
  2. Imaging:
    * Radiographs = round, well-circumscribed intracortical lesion with radiolucent nidus, surrounding reactive sclerosis, benign periosteal reaction
    • Nidus is always less than 1.5cm (sclerosis may extend beyond)
      * CT (thin slice) = identifies radiolucent nidus (often key to diagnosis)
      * MRI = also can show nidus as well as adjacent edema (not needed routinely)
  3. Treatment
  • Expectant observation and NSAIDs
    • Pain is self-limiting treated with NSAIDs, burns out on average in 3 years
  • Radiofrequency ablation (RFA)
    • Failure of NSAIDs
    • Contraindicated if adjacent to nerve roots or spinal cord
    • Recurrence = 10-15%
  • Surgical resection/currettage
    • Indicated if close to spinal cord/nerve root/skin, painful scoliosis, digits
      1. Differential for cortical osteoid osteoma
  • Cortical bone abscess
  • Stress fracture (linear radiolucency)
  • Intracortical osteosarcoma
  • Osteoblastoma (>2cm)
  1. Differential for an intramedullary osteoid osteoma
  • Brodies abscess
  • Osteoblastoma
  • Bone island
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35
Q

Osteoblastoma

Classification

Age

Presentation

Location

Imaging

Treatment

DDx

A
  1. Classification - Benign aggressive
  2. Age = 10-30
  3. Presentation
  • Slow, progressive dull, aching pain
    • Differs from osteoid osteoma in that it is less severe, not night pain, not relieved with ASA
  1. Location
  • Most common = posterior elements of the spine
  • 2/3 are cortically-based, 1/3 are medullary-based
  1. Imaging
  • Radiographs = radiolucent nidus >2cm
    • Surrounding reactive sclerosis
    • Expansile with neocortex
  • CT = indicated to evaluate extent of lesion
  1. Treatment
  • Currettage and bone grafting or en bloc resection
  • Not self limiting so observation not indicated
  1. Differential diagnosis
  • Osteoid osteoma
  • Brodies abscess
  • ABC
  • Osteosarcoma
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36
Q

Bone Island

Classification

Presentation

Location

Imaging

Treatment

Assoc Conditions

A
  1. Classification - Benign latent (?)
  2. Presentation
    * Incidental finding
  3. Location
  • Most common = pelvis and proximal femur
  • Medullary cavity
  1. Imaging
  • Radiographs = round focus of dense bone occasionally with radiating spiculus of bone
  • MRI = no surrounding edema
  1. Treatment
  • None
  • Repeat radiographs if diagnosis is in doubt
  1. Associated Conditions
    * Osteopoikilosis = hereditary multiple bone islands
37
Q

Enchondroma

Classificatino

Age

Presentation

Location

Imaging

Treatment

Assoc Conditions

DDx

A
  1. Classification - Benign latent (cartilage)
  2. Age = 20-50
  3. Presentation
  • Asymptomatic, incidental finding most common
  • Pain may be associated with:
    • Lesions in small bones of hands/feet
    • Pathological fracture
    • Malignant transformation (<1% Chondrosarcoma)
  1. Location
  • Most common = hand
    • Also feet, diaphysis and metaphysis of long bones
  • Medullary cavity
  1. Imaging
  • Radiographs = rings and stippled calcifications within the medullary cavity
    • Minimal endosteal erosion (<50%)
    • Cortical expansion and thinning may be present in hands and feet (not in long bones)
  1. Treatment
  • Observation
  • Intralesional currettage and bone grafting
    • Indications:
      • Large lesion at risk of recurrent fracture
      • Radiographs suspicious for low-grade chondrosarcoma
      • Serial radiographs showing change in lesion
  1. Associated Conditions
  • Ollier disease
    • Spontaneous mutation
    • Multiple enchondromas
    • Associated with shortening and bowing deformities
    • 25-30% chance of malignant degeneration to low grade chondrosarcoma
  • Maffucci syndrome
    • Multiple enchondromas and soft-tissue angiomas
    • Up to 100% chance of malignant degeneration to low grade chondrosarcoma
      1. DDx for solitary enchondroma
  • Bone infarct
  • Chondrosarcoma
  • Chondroblastoma (if affects end of bone)
  • GCT (if affects end of bone and no calcifications)
38
Q

Periosteal Chondroma

Classification

Age

Presentation

Location

Imaging

Treatment

A
  1. Classification: Benign active (?) (Cartilage)
  2. Age = 10-30
  3. Presentation
    * Pain or incidental finding
  4. Location
    * Surface of long bones and hands
  5. Imaging
  • Radiographs = surface lesion
    • Saucerization of underlying cortex with rim of sclerosis
    • Variable calcification
  1. Treatment
  • Observation
  • Marginal exicision
    • Symptomatic
39
Q

Osteochondroma

Classification

Presentation

Imaging

Treatment

Assoc Conditions

A
  1. Classification - Benign (Cartilage)
  2. Presentation
  • Asymptomatic, palpable immobile mass
  • Pain if inflamed overlying bursa, fracture of stalk, nerve compression, malignant degeneration (higher risk in sessile form)
  1. Imaging
  • Radiographs = Sessile or pedunculated
    • Cortex of stalk continuous with adjacent bone
    • Medullary canal continuous with stalk (“corticomedullary continuity”)
    • Pedunculated grow away from joint
  1. Treatment
  • Observation
    • Asymptomatic
  • Marginal resection at base of stalk including cartilage cap (delay until skeletal maturity preferred)
    • Indications = symptomatic, cosmetic, vascular or nerve compression
      1. Associated condition
  • Multiple Hereditary Exostosis
    • Autosomal dominant mutation in EXT 1, EXT 2
      • EXT-1 has more serious disease manifestations
    • Associated with:
      • Short stature
      • Metaphyseal widening
      • Primarily sessile lesions
      • Long bone deformities
      • Higher risk of malignant transformation (5-10% Chondrosarcoma)
  • Trevor’s disease
    • Osteochondroma arising from epiphysis
      • Most commonly located in tarsals followed by knee
40
Q

Chondroblastoma

Classification

Age

Presentation

Location

Imaging

Histology

Treatment

DDx

A
  1. Classification - Benign Aggressive (Chondroid)
  2. Age = <25 (80%)
  3. Presentation
  • Progressive pain, limp, decreased ROM, tenderness
  • Benign pulmonary metastasis (<1%)
  1. Location
  • Most common = knee (distal femur, proximal tibia)
    • Also proximal humerus, proximal femur, calcaneus, flat bones
  • Epiphysis or apophysis, often with extension into the metaphysis
  1. Imaging
  • Radiographs = well circumscribed lytic lesion with sclerotic rim
    • Stippled calcification (25-40%)
    • May have cortical expansion
  1. Histology
    * ‘Chicken Wire Calcifications’ surround chondroblasts
  2. Treatment
  • Extended intralesional curretage with bone grafting
    • Adjuvants include phenol or liquid nitrogen to reduce recurrence
  • Surgical resection of benign pulmonary metastasis when present
  1. Differential diagnosis
  • Clear cell chondrosarcoma
  • Bone abscess
  • Osteonecrosis
  • Intraosseous ganglion
  • GCT
  • Osteoblastoma
  • Enchondroma
41
Q

Chondromyxoid Fibroma

Classification

Age

Presentation

Location

Imaging

Histology

Treatment

DDx

A
  1. Classification - Benign active (chondroid)
  2. Age = 10-30
  3. Presentation
  • Pain and mild swelling
  • May be incidental finding
  1. Location
  • Most common = long bones of lower extremity and pelvis
    • Also hands and feet
  • Metaphysis
  1. Imaging
  • Radiographs = lytic, eccentric metaphyseal lesion
    • Thinning and expansion of adjacent cortical bone
    • Sharp sclerotic rim
  1. Histology
    * Stellate cells
  2. Treatment
    * Intralesional currettage and bone grafting
  3. Differential diagnosis:
  • NOF
  • Fibrous dysplasia
  • ABC
  • Osteofibrous dysplasia (if in tibia)
  • GCT (if extends to epiphysis)
42
Q

Nonossifying Fibroma (NOF)

Classification

Age

Presentation

Location

Imaging

Treatment

Assoc Conditions

A
  1. Classification - Benign latent (fibrous)
  2. Age = 5-15
    * 30% of children with open physes have NOF
  3. Presentation
  • Asymptomatic, incidental finding
  • Pathological fracture
  1. Location
  • Most common = long bones of lower extremities
  • Cortically based, start in metaphysis and migrate to diaphysis
  1. Imaging
  • Radiographs = eccentric, lytic, ‘bubbly’
    • Cortically based lesion with sclerotic rim
    • Cortex may be expanded and thinned
      • As patient reaches skeletal maturity the lesion ossifies and becomes sclerotic
  1. Treatment
  • Observation
    • Serial radiographs should be considered for larger lesions
  • Intralesional currettage and bone grafting
    • If symptomatic and large lesion
  • Pathological fractures are treated as per fracture and allowed to heal
    • Consider intralesional currettage and bone grafting if high risk of recurrence
  1. Associated conditions
  • Familial multifocal
  • Neurofibromatosis
  • Jaffe-Campanacci syndrome
43
Q

Fibrous Dysplasia

Classification

Age

Presentation

Location

Imaging

Histology

Treatment

Assoc Conditions

A
  1. Classification - Benign active (fibrous)
  2. Age = all ages (75% seen in patients younger than 30)
  3. Presentation
  • Asymptomatic, incidental finding
  • Pathological or fatigue fractures resulting in pain
  1. Location
  • Most common = proximal femur, rib, maxilla, tibia (can affect any bone)
  • Medullary cavity
  • Monostotic (single bone) or polyostotic (more than one bone)
  1. Imaging
  • Radiographs = central, lytic lesion
    • Often ground glass appearing in diaphysis/metaphysis
    • Surrounding sclerotic rim
    • May be expansile with cortical thinning
      • Bowing deformity in proximal femur (Shepherd’s crook) or tibia
      • Vertebral collapse and kyphoscoliosis
  1. Histology
  • “Chinese letters” or “alphabet soup” appearance
    • Immature fibrous tissue surrounding islands of woven bone
  1. Treatment
  • Observation
    • Asymptomatic
  • Bisphosphonate
    • Indicated in symptomatic polyostotic fibrous dysplasia
  • Internal fixation with bone grafting
    • Indications:
      • Pain
      • Impending/actual pathological fracture
      • Severe deformity
      • Neurological compromise (spine)
    • Technique – IM nail preferred over plate
      • Do not use cancellous autograft as it turns into dysplastic woven bone
      • Use cortical allograft
  • Osteotomies
    • Indication – coxa vara deformity (intertrochanteric osteotomy)
      1. Associated conditions
  • McCune-Albright syndrome
    • Triad of polyostotic fibrous dysplasia, precocious puberty, café-au-lait spots (coast of Maine)
  • Mazabraud syndrome
    • Polyostotic fibrous dysplasia and multiple intramuscular myxomas
  • Cranial deformities and blindness with craniofacial involvement
44
Q

Osteofibrous Dysplasia

Classification

Age

Presentation

Location

Imaging

Treatment

A
  1. Classification - Benign active (fibrous)
  2. Age = <10
  3. Presentation
  • Painless swelling over anterior border of tibia
  • Anterior or anterolateral tibial bowing
    • Pseudoarthrosis in 10-30%
  1. Location
  • Most common = anterior tibia
  • Cortically-based, usually diaphyseal
  1. Imaging
  • Radiographs = eccentric, anterior tibia cortical lytic lesion surrounded by sclerosis
    • No periosteal reaction
  1. Treatment
  • Observation (avoid surgery if possible)
  • Bracing – if deformity present
  • Deformity correction
    • Rarely needed, perform after skeletal maturity if significant deformity present
45
Q

Desmoplastic Fibroma

Classification

Age

Presentation

Location

Imaging

Treatment

A
  1. Classification - Benign aggressive (fibrous)
    * Extremely rare
  2. Age = 10-30
  3. Presentation
    * Pain, mass, swelling
  4. Location
  • Any bone
  • Metaphysis
  1. Imaging
  • Radiographs = lytic lesion central in the metaphysis with soap-bubbly/trabeculated appearance
    • May appear aggressive
  1. Treatment
    * Wide surgical resection vs. intralesional currettage
46
Q

Eosinophilic Granuloma

AKA Langerhans cell histiocytosis, histiocytosis X

Classification?

Age

Presentation

Location

Imaging

Histology

Treatment

A
  1. Classification -
  2. Age = <20
  3. Presentation
  • Solitary disease (EG)
    • Pain, swelling
  • Hand-Schuller-Christian disease
    • Chronic, disseminated form with visceral involvement
    • Triad = multiple lytic skull lesions, diabetes insipidus, exopthalmus
  • Letterer-Siwe disease
    • Infantile, fatal
  1. Location
  • Most common = skull, ribs, clavicle, scapula, vertebrae, long bones, pelvis
  • Can occur in any bone
  1. Imaging
  • Radiographs = ‘the great mimicker’
    • Diaphyseal lesions = classically punched out lytic lesions
      • Cortex may be thinned or destroyed
      • May have periosteal reaction (can be geographic or permeative)
    • Vertebral plana, kyphosis
    • Cranial lesions = multiple punched out lytic lesions
      1. Histology
  • Mixed inflammatory cell infiltrate
    • Langerhans cells = indented nuclei (‘coffee bean’)
      • Stain with CD1a
      • On electron microscope = Birbeck granules (‘tennis racket’)
    • Eosinophils = pink cytoplasm
    • Giant cells are present
      1. Treatment
  • Observation – solitary lesions
  • Corticosteroid injections (intralesional) – solitary lesions
  • Low dose irradiation
    • Reserved for lesions in the spine or lesions not amenable to injection or surgery
  • Bracing
    • Prevents kyphosis in vertebra plana (90% effective)
  • Chemotherapy
    • Reserved for Hand-Schuller-Christian disease
  • Intralesional currettage and bone grafting
    • Risk of impending fracture or articular involvement
47
Q

Unicameral Bone Cyst (UBC)

Classification

Age

Presentation

Location

Imaging

Treatment

A
  1. Classification - Benign active (cystic)
  2. Age = <20
  3. Presentation
    * Most common = pathologic fracture

4, Location

  • Most common = proximal humerus, proximal femur, ilium, calcaneus
  • Medullary cavity
  1. Imaging
  • Radiographs = central, lytic, well-demarcated metaphyseal lesion
    • Expansion and thinning of the cortex
    • Expansion is no wider than the physis
    • ‘Fallen Leaf Sign” – pathognomonic
      • Pathologic fracture where a cortical fragment falls into the base of the lesion
    • Start adjacent to physis (active) then progress towards diaphysis (latent)
    • Trabeculated appearance after multiple fractures
  • MRI = bright on T2, dark on T1
  1. Treatment
  • Observation – asymptomatic lesions
  • Pathological fracture:
    • Proximal humerus – nonop
    • ~15% of lesions fill in with native bone after fracture
  • Intralesional injection of methylprednisolone
    • Indicated for active lesions, may require multiple injections
  • Intralesional currettage, bone grafting and ORIF
    • Indicated in proximal femur fractures at high risk of pathological fracture or re-fracture
    • Symptomatic latent cysts that have not responded to injections
48
Q

Aneurysmal Bone Cyst (ABC)

Classification

Age

Presentation

Location

Imaging

Histology

Treatment

Assoc Conditions

DDx

A
  1. Classification - Benign aggressive (cystic)
  2. Age = <20 (75%)
  3. Presentation
  • Most common = pain, swelling
  • Pathological fracture
  • Neurological symptoms with spine involvement
  1. Location
  • Most common = knee (distal femur, proximal tibia)
    • Also pelvis, posterior elements of spine
  • Metaphysis, eccentric
  1. Imaging
  • Radiographs = expansile, eccentric, lytic lesion with soap-bubbly appearance
    • Neocortex
    • Can expand wider than the width of the physis
  • MRI = fluid-fluid levels (separation of serum from blood products)
  1. Histology
  • Blood-filled cysts without a true endothelial lining
  • Lining contains giant cells and spindle cells
  • “Snakes and blood”
  1. Treatment
  • Extended intralesional currettage and bone grafting
    • Consider adjuvants phenol and liquid nitrogen
    • If pathological fracture, treat fracture nonoperative first then currettage (unless spontaneous resolution of ABC)
  1. Associated conditions
  • Arises from other tumours 30% of cases
    • GCT, chondroblastoma, CMF, NOF, osteoblastoma, FD
  • Telangiectactic osteosarcoma – radiographic and histological differential
  1. Differential diagnosis
  • UBC
  • CMF
  • GCT
  • Telangiectatic osteosarcoma
49
Q

Giant Cell Tumour

Classification

Age

Presentation

Location

Imaging

Histology

Treatment

Assoc Conditions

A
  1. Classification - Benign aggressive
  2. Age = 30-50
  3. Presentation
  • Pain and swelling
  • Pathological fracture
  1. Location
  • Most common = knee (distal femur, proximal tibia)
    • Distal radius, proximal humerus, proximal femur, sacral ala, pelvis
    • Vertebral body when spine involved
  • Metaphysis, epiphysis, apophysis
  • Eccentric
  1. Imaging
  • Radiographs = eccentric, lytic lesion located in metaphysis/epiphysis
    • Often extending to subchondral bone
    • Expands bone
    • Neocortex

​6. Histology

  • Scattered giant cells on background of mononuclear stromal cells (neoplastic cells)
    7. Treatment
  • Extensive intralesional currettage and bone grafting or cement
    • Consider adjuvants phenol or liquid nitrogen
    • 10-15% recurrence
      • Adjuvants (PMMA) decrease recurrence compared to bone graft
    • If cement used WB can be immediate
  • En bloc resection and reconstruction
  • Denosumab (controversial)
    • Assoc complications:
      • Increased recurrence, arthralgia, headache, nausea, fatigue, pain, anemia, hypercalcemia and osteonecrosis in jaw
  • Radiation
  • Lung metastasis (2%)
    • Thoracotomy, radiation, chemo, or observation
    • 10-15% die due to mets
      1. Associated conditions
  • Malignant transformation to high grade sarcoma (<1%)
  • Secondary ABC
50
Q

What is the Enneking Classification of Malignant Bone Tumours?

A
  1. Stage IA = low grade, intracompartmental
  2. Stage IB = low grade, extracompartmental
  3. Stage IIA = high grade, intracompartmental
  4. Stage IIB = high grade, extracompartmental
  5. Stage III = metastatic disease

A = confined to bone, no soft tissue involvement

B = penetration of the cortex with a soft tissue mass

51
Q

Intramedullary Osteosarcoma

Classification

Age

Presentation

Location

Imaging

Histology

Staging

Treatment

Prognosis

Assoc Conditions

A
  1. Classification - Malignant
  2. Age = most common 2nd decade (late peak in 6th decade)
  3. Presentation
  • Constant pain (day/night), unrelieved by analgesics
  • Swelling, decreased ROM, limp, weakness
  • Pathological fracture (10%)
  1. Location
  • Most common = knee (distal femur, proximal tibia)
    • Also proximal humerus, pelvis, proximal femur
  • Typically, medullary cavity
  1. Imaging
  • Radiographs = mixed blastic and lytic non-geographic lesion
    • Sun-burst periosteal reaction
    • Codman’s triangle
    • Soft-tissue mass
  • MRI full-length bone involved = assess for skip lesions, neurovascular involvement, soft tissue mass
  • Bone scan = primary lesion very hot
    • Evaluate for skip lesions
  • CT chest = order at presentation and assess for lung mets
  1. Histology
    * ‘Lacelike pattern’ of osteoid formed by malignant cells (atypia, abnormal mitotic figures, high nuclear to cytoplasmic ratio)
  2. Staging
  • Enneking
    • Most common = Stage IIB (high grade, extracompartmental, no metastasis)
  1. Treatment
  • Neoadjuvant chemotherapy
  • Restage (MRI local, CT chest, bone scan, radiographs)
  • Surgery
    • •Limb-sparing surgery with wide-margin resection and reconstruction (preferred)
      • Reconstructive options include tumour prosthesis, intercalary allograft, APC, rotationplasty
    • Amputation
      • Indications:
        • Pathological fracture
        • Encasing neurovascular bundle
        • Poor response to chemotherapy
  • Adjuvant chemotherapy
    9. Prognosis
  • 70% 5 year survival for localized osteosarcoma in an extremity
    • 25% 5 year survival for localized pelvic osteosarcoma
  • Poor prognostic factors
    • Advanced tumour stage (most important)
      • Metastatic disease is poor prognostic factor
      • Most common site = lung (61%), bone (16%)
    • Response to neoadjuvant chemotherapy
      • >90% tumour necrosis associated with increased survival
    • Skip lesions
      • Occur in 10%, similar prognosis as lung metastasis
    • Inadequate surgical margins
    • Vascular involvement
    • Elevated LDH, ALP
    • Expression of VEGF, P-glycoprotein
    • Expression of multi-drug resistance (MDR)
    • Axial/pelvic involvement
      1. Associated conditions
  • Retinoblastoma tumour suppressor gene (RB1) carriers
  • Paget disease
  • Prior radiation
  • Rothmund-Thomson syndrome
52
Q

Parosteal Osteosarcoma

Classification

Age

Presentation

Location

Imaging

Treatment

DDx

A
  1. Classification - Malignant
  2. Age = 20-45
  3. Presentation
  • Painless mass of long duration
  • May have limited joint ROM, limp, pain
  1. Location
  • Most common = posterior distal femur (75%)
    • Also proximal tibia, proximal humerus
  • Surface of metaphysis
  1. Imaging
  • Radiographs = dense/ossified, lobulated mass arising from the cortex
  • MRI full length bone = assess for skip lesions, soft tissue involvement, marrow involvement
  • Bone scan = lesion will be hot
    • Assess for skip lesions
  • CT chest = assess for lung mets
  1. Treatment
  • Wide local surgical resection
  • No chemo or radiation
  1. Differential diagnosis
  • Parosteal osteoma
  • Melorheostosis
  • Sessile osteochondroma
  • Fracture callus
  • Myositis ossificans
53
Q

Periosteal Osteosarcoma

Classification

Age

Presentation

Location

Imaging

Treatment

A
  1. Classification - Malignant
    * Extremely rare
  2. Age = 15-25 ‘
  3. Presentation
    * Pain
  4. Location
  • Most common = femoral or tibial diaphysis
  • Cortical/periosteal (no medullary canal involvement)
  1. Imaging
  • Radiographs = sunburst periosteal reaction
    • Underlying cortex may be saucerized (no medullary involvement)
  • CT chest = assess for lung mets
  • Bone scan = hot
  1. Treatment
  • Same as intramedullary osteosarcoma
    • Neoadjuvant Chemo
    • Restage
    • Wide margin resection
    • Adjuvant Chemo
54
Q

Telangiectatic Osteosarcoma

Classification

Age

Presentation

Location

Imaging

Histology

Treatment

A
  1. Classification - Malignant
    * Rare
  2. Age, presentation = similar to intramedullary osteosarcoma
    * Most common 2nd decade (late peak in 6th decade)
  • Constant pain (day/night), unrelieved by analgesics
  • Swelling, decreased ROM, limp, weakness
  • Pathological fracture (10%)
  1. Location
    * Proximal humerus, proximal femur, distal femur, proximal tibia
  2. Imaging
  • Radiographs = purely lytic lesion
    • Expansile, occasionally obliterates cortex
  • MRI = fluid-fluid levels, extensive edema
  1. Histology
  • Differentiates from ABC
  • Gross = “bag of blood”
  • Atypical mitosis
  1. Treatment
  • Same as intramedullary osteosarcoma
    • Neoadjuvant Chemo
    • Restage
    • Wide margin resection
    • Adjuvant Chemo
55
Q

Secondary Osteosarcoma

Classification

Arises from

Prognosis

A
  1. Classification - Malignant
  2. Arises from:
  • Pagets
  • Fibrous dysplasia
  • Bone infarct
  • Chronic osteomyelitis
  • Osteogenesis imperfecta
  • Irradiation
  1. Prognosis
    * Very poor (as per CORR)
56
Q

Undifferentiated Pleomorphic Sarcoma of Bone

AKA Malignant Fibrous Histiocytoma

Classification

Age

Presentation

Location

Imaging

Histology

Treatment

A
  1. Classification - Malignant
  2. Age = 20-80 (most common >40)
  3. Presentation
  • Pain
  • Swelling, limp, decreased ROM
  • Pathologic fracture
  1. Location
  • Distal femur, proximal tibia, proximal humerus
  • Metaphysis
  1. Imaging
  • Radiographs = lytic lesions, often with cortical destruction and soft tissue mass
    • Variable periosteal reaction
  • MRI = characterize lesion
  1. Histology
    * Spindle cells arranged in herringbone pattern
  2. Treatment
    * Similar to intramedullary osteosarcoma
    • Neoadjuvant Chemo
    • Restage
    • Wide margin resection
    • Adjuvant Chemo
57
Q

Chondrosarcoma

Classification

Age

Presentation

Location

Imaging

Histology

Treatment

Assoc Conditions

Subtypes

Prognosis

A
  1. Classification - Malignant
  2. Age = 40-75
  3. Presentation
  • Pain of prolonged duration
  • Slow growing firm mass
  • Pathological fractures
  1. Location
    * Most common = pelvis, proximal femur, scapula
  2. Imaging
  • Radiographs
    • Low grade = similar appearance to enchondroma
    • High grade = cortical destruction and soft tissue mass
    • Dedifferentiated = low grade lesion with superimposed high grade destructive area
  • MRI = assess for cortical destruction, marrow involvement, soft tissue involvement
  1. Histology
    * Low grade = bland appearance, few mitotic figures
    * High grade = hypercellular cartilaginous lesion with atypical cells that permeate the bone trabeculae
  2. Treatment
  • Intralesional currettage or wide resection = grade I
  • Wide surgical resection = grade II, III, dedifferentated and pelvic
  • ***NOTE – chemotherapy and radiation are generally not effective
  1. Associated conditions
  • Ollier’s
  • Mutliple hereditary exostosis
  • Osteochondroma
  • Enchondroma
  • Maffucci’s
  1. Subtypes
  • Clear cell chondrosarcoma
    • Epiphysis
    • Confused with chondroblastoma
    • Histology shows extensive clear cytoplasm
    • Treatment is wide surgical resection
  • Mesenchymal chondrosarcoma
  1. Prognosis
  • Secondary chondrosarcoma is better than primary
    • Result is low grade chondrosarcoma
  • Dedifferentiated chondrosarcoma is the worst
58
Q

Ewing Sarcoma

Classification

Age

Presentation

Location

Imaging

Histology

Genetics

Bone Marrow Biopsy

Treatment

Prognosis

A
  1. Classification - Malignant
  2. Age = 5-25
    * Median age 15, >50% adolescents
  3. Presentation
  • Pain
  • Often fever (20-28% - mistaken for infection)
  • Swelling, limp, decreased ROM
  • Palpable mass (34%)
  • Pathologic fracture (15%)
  • Delayed presentation/diagnosis common
  1. Location
  • Pelvis, distal femur, proximal tibia, diaphysis of femur, proximal humerus
    • Presents equally in flat and long bones
  • Diaphysis
  1. Imaging
  • Radiographs = ill-defined, motheaten, permeative lytic bone destruction
    • Periosteal reaction (onion skin or sunburst)
  • MRI = assess for soft tissue and marrow involvement
    • Soft tissue component in 80%
  • Bone scan = hot
  • CT chest = assess for lung mets
  1. Histology
  • Small round blue cells
  • Immunohistochemical staining positive for CD99 (95%), MIC-2
  1. Genetics
  • t(11:22) [11:22 chromosomal translocation]
    • Spontaneous translocation
    • Produces EWS/FLI1 identified by PCR
  1. Bone Marrow Biopsy
    * Done because Ewing’s sarcoma can metastasize via the marrow
  2. Treatment
  • Neoadjuvant chemotherapy (4-8 cycles)
  • Limb-sparing surgery with wide-margin resection and reconstruction (preferred)
    • Consider amputation for:
      • Extremely large tumours involving NV structures
      • Unmanageable or displaced pathologic fracture
      • Lesions in the foot or ankle
  • Adjuvant chemo
  • Radiation (instead of surgery) for inoperable or metastatic disease
  • Adjuvant radiation
    • Reserved for positive margins
  1. Prognosis
  • 80% 5 year survival for localized extremity
    • 63% 10y survival
  • 39% 5 year survival for metastasis
    • 32% 10y survival
    • Most commonly to lung and bone
  • Poor prognostic factors
    • Metastatic disease (most important)
      • Especially nonpulmonary mets and distant mets
    • Large tumour (>8cm, >100-200mL)
    • Pelvic tumour
    • Chemotherapy response (<90% necrosis)
    • Older age (>14)
    • Male (More common than female 1.5:1)
    • Elevated LDH (>200)
    • Relapse within 2y
59
Q

Chordoma

Classification

Age

Presentation

Location

Imaging

Histology

Treatment

DDx

A
  1. Classification - Malignant
  2. Age = >40
  3. Presentation
  • Insidious onset of low back or sacral pain
  • Bowel/bladder symptoms
  • 50% palpable on rectal exam
  • Motor/sensory deficits rare (occur below S1)
  1. Location
  • Sacrococcygeal region (50%)
    • Spheno-occipital region (35%)
    • Spine (15%)
  • Central, always has an anterior component
  • Metastasizes late (lung)
  1. Imaging
  • Radiographs = difficult to assess due to overlying bowel gas
  • CT = midline bone destruction with soft tissue mass
    • Calcifications may be present in soft tissue
  • MRI = lesion bright on T2
  1. Histology
  • Transrectal biopsy contraindicated
  • Physaliferous cell (signature cell) contains vacuoles and appears bubbly
  • Keratin positive (differentiated from chondrosarcoma)
  1. Treatment
  • Wide surgical resection
  • Radiation
    • Reserved for inoperable tumours, positive margins, local recurrence
  1. Differential diagnosis
  • Chondrosarcoma
  • Plasmacytoma
  • Metastasis
  • Osteomyelitis
  • Lymphoma
60
Q

Adamantinoma

Classification

Age

Presentation

Location

Imaging

Histology

Genetics

Treatment

DDx

A
  1. Classification - Malignant
  2. Age = 20-40
  3. Presentation
  • Pain and tenderness to anterior tibial border
  • Occasional tibial deformity or mass
  • History of preceding trauma common
    4. Location
  • Most common = tibial diaphysis (90%)
  • Intracortical or intramedullary
  1. Imaging
  • Radiographs = multiple well circumscribed lucent defects (soap-bubbly appearance)
  • No periosteal reaction
  1. Histology
    * Nests of epithelial cells in a benign fibrous stroma
  2. Genetics
    * Controversial whether evolves from osteofibrous dysplasia
  3. Treatment
  • Wide margin surgical resection
    • Reconstruction often with intercalary allograft
  • ***Note – late mets to lung, bones, lymph nodes
    • Requires long term followup
  1. Differential diagnosis
  • Osteofibrous dysplasia
  • Fibrous dysplasia
  • NOF
  • Osteomyelitis
61
Q

What are the general treatments for malignant bone tumours?

[3x3 table]

62
Q

Multiple Myeloma

Classification

Age

Presentation

Location

Imaging

Labs

Histology

Treatment

A
  1. Classification - Systemic (Marrow)
  2. Age = >40
  3. Presentation
  • Bone pain
  • Pathologic fractures
  • Cord compression
  • Recurrent infections
  1. Location
    * Most common = skull, spine, long bones
  2. Imaging
  • Radiographs = multiple, punched out lytic lesions throughout skeleton
    • No surrounding sclerosis
    • Skeletal survey to look for additional lesions (bone scan cold)
  1. Labs
  • SPEP, UPEP
  • Anemia, hypercalcemia, elevated creatinine, elevated ESR
    • “CRAB”
      • Calcium high
      • Renal insufficiency
      • Anemia
      • Bone lesions
  1. Histology
  • Plasma cells with eccentric nuclei
    • Chromatin arranged in ‘clockface’
  • Immunohistochemistry = CD38+
  1. Treatment
  • Chemotherapy (mainstay)
  • Stem cell transplant - not curative but increases survival
  • Bisphosphonates – decreases number of bone lesions, bone pain and lowers serum calcium
  • Surgical stabilization – pathological or impending fractures
    • Treatment similar to metastatic disease
      • IM devices preferred
      • Protect full length of bone
63
Q

Solitary Plasmacytoma

A
  • Plasma cell tumour in a single skeletal location
  • Progresses to multiple myeloma in 50% of cases
  • Negative SPEP/UPEP/bone marrow aspirate

Treatment

  • Radiation alone
64
Q

Lymphoma

Classification

Age

Presentation

Location

Imaging

Histology

Treatment

Prognosis

A
  1. Classification - Systemic (marrow)
  2. Age = 35-55
  3. Presentation
  • B symptoms = fever, weightloss, night sweats
  • Constant pain unrelieved with rest
  • Large tender, warm soft tissue mass
  • Pathologic fracture (25%)
    4. Location
  • Most common = femur, spine, pelvis, ribs
    5. Imaging
  • Radiographs = lytic, permeative lesions
    • Often subtle bone destruction
    • Soft tissue mass
    • Multiple sites is common
    • Ivory vertebrae
  • CT chest, abdo, pelvis = required for staging
  • MRI = extensive marrow involvement with soft tissue mass
  • PET scan = useful for staging and followup
  1. Histology
  • Small round blue cell
  • Immunohistochemical staining = CD20+, CD45+
  1. Treatment
  • Chemotherapy
  • Radiation
    • Reserved for persistent disease
  • Surgery
    • Only for pathological fractures
  1. Prognosis
    * 70% 5 year survival for disseminated disease
65
Q

Lipoma

Classification

Age

Presentation

Location

Imaging

Histology

Treatment

A
  1. Classification - Benign (fat)
  2. Age = 40-60
  3. Presentation
  • Superficial lipoma – soft, painless, mobile mass
  • Deep lipoma – usually intramuscular, fixed, painless
  1. Location
  • Superficial
    • Upper back, shoulders, arms, buttocks, proximal thigh
  • Deep
    • Thigh, shoulder, calf
  1. Imaging
  • XR
    • Radiulucent area within radiodense skeletal muscle
  • MRI
    • Isointense with fat on all sequences
    • T1 = bright
    • T2 = intermediate
    • Fat suppressed = suppresses
  1. Histology
    * Mature fat cells
  2. Treatment
  • Observation
  • Marginal resection
    • Indicated when symptomatic, growing rapidly
66
Q

Atypical Lipoma

AKA Well differentiated liposarcoma

ATL vs WDL

Location

Population

Presentation

Imaging

Histology

Genetics

Treatment

Prognosis

A

ALT vs WDL

  • Tumours with identical histology but differ in anatomic location and clinical outcomes
  • Precancerous
    • Risk of malignant transformation depends on location and lesional duration

ALT

  • Location
    • Extremity based or superficial trunk
      • Most common = thigh
    • Deep to fascia
      • ~25% of deep lipomatous masses are ALT
  • Population
    • Middle age, peak 50-60s
    • M=F
  • Presentation
    • Deep, large, painless, enlarging mass
  • Imaging
    • MRI
      • Similar to lipomas (isointense to fat)
        • Differentiated by:
          • Deep to fascia
          • Larger (>10cm)
          • Thick fibrous septae (>2cm)
          • Post-gad enhancement
  • Histology
    • In contrast to lipoma:
      • Pleomorphism
      • Nuclear atypia
      • Hyperchromatic stromal cells
  • Genetics
    • MDM2 amplification (distinguishes from lipoma)
    • CDK4 also amplified
  • Treatment
    • Marginal excision
      • Wide excision decreases local recurrence but may be overly morbid for benign tumour
      • Adjuvant therapies not beneficial
  • Prognosis
    • 100% survival
    • 10% local recurrence (range 8-50%)
      • Avg 6-8y after surgical excision
      • 52% re-recurrence
    • 0-5% risk of malignant dedifferentiation

WDL

  • =ALTs in anatomical locations not amenable to complete surgical resection
  • Location
    • Retroperitoneum
      • 50% of lipomatous masses are WDLs and 45% are dedifferentiated liposarcomas
    • Mediastinum
    • Paratesticular
  • Presentation
    • Larger than ALTs prior to symptoms/diagnosis
    • Pain, neuro symptoms, GI bleeding possible
  • Imaging
    • CT C/A/P
      • Required for retroperitoneal masses for planning and staging
  • Treatment
    • Wide surgical excision
      • ~50% of patients require organ removal to achieve en bloc resection
    • Debulking surgeries for recurrent retroperitoneal tumours have a role in prolonging survival
  • Prognosis
    • Mortality rate >80%
      • Avg 6-11y to death
    • Lack metastatic potential but incurable
    • 10-20% risk of malignant dedifferentiation
67
Q

Intramuscular Hemangioma

Classification

Age

Presentation

Location

Imaging

Treatment

A
  1. Classification - Benign (vascular)
  2. Age = <30
    * Most common soft tissue mass in kids
  3. Presentation
    * Pain
  4. Location
    * Most common = lower extremities
  5. Imaging
  • Radiographs = phleboliths or calcifications
    • Adjacent bony erosion may be present
  • US = helps to differentiate type of lesion
  • MRI = increased signal intensity on T1 and T2
    • “Bag of worms”
  1. Treatment
  • Observation, NSAIDs, compression stockings
    • Most lesions
  • IR embolization or sclerotherapy
    • Reserved for large, painful lesions failing non-op treatment
68
Q

Schwannoma/Neurilemoma

Classification

Age

Presentation

Location

Imaging

Histology

Treatment

A
  1. Classification - Benign (nerve)
    * Benign encapsulated tumor on surface of peripheral nerves composed of Schwann cells
  2. Age = 20-50
  3. Presentation
  • Usually asymptomatic
  • Pain associated with stretch or activity
  • Positive tinel sign
  1. Location
    * Flexor surfaces of extremities, pelvis
  2. Imaging
  • MRI
    • T1 = low signal
    • T2 = high signal
      • Target sign
        • Low signal intensity surrounded by high intensity on T2
    • Enhances with gadolinium
    • Nerve may be seen entering and exiting the schwannoma
    • ‘Split fat sign’
      • Fine fat deposition around the lesion and is usually seen as a tapered rim of fat signal adjacent to the proximal and distal ends of the lesion on T1-weighted coronal or axial images
      • Split fat is produced as a mass grows and normal intermuscular fat is displaced and effaced around the lesion
  1. Histology
  • Verocay body – pathognomonic
    • Two rows of aligned nuclei in a palisading formation
  1. Treatment
  • Observation – asymptomatic lesions
  • Marginal excision with nerve fibre preservation – symptomatic
69
Q

Nodular Fasciitis

Classification

Age

Presentation

Location

Imaging

Treatment

A
  1. Classification - Benign (Reactive/Fibrous)
  2. Age = 20-40
  3. Presentation
  • Rapidly enlarging mass over 1-2 weeks (usally 1-2cm in size)
  • Painful in ~50%
  1. Location
    * Volar forearm, back, chest, head, neck
  2. Imaging
  • MRI = nodularity, usually small
    • Extension along fascial planes
    • Enhances with gadolinium
  1. Treatment
    * Marginal resection
70
Q

Intramuscular Myxoma

Classification

Age

Presentation

Location

Imaging

Histology

Treatment

Associated Conditions

A
  1. Classification - Benign (Mesechymal/Mucoid)
  2. Age = 40-70
  3. Presentation
    * Painless mass (20% painful)
  4. Location
  • Most common = thigh, buttock, shoulder, upper arm
  • Often close to neurovascular structures
  1. Imaging
  • MRI = homogenous
    • T2 = high signal
    • T1 = low signal
    • Within muscle groups
  1. Histology
  • Minimal cellularity, no atypia
  • Cells suspended in abundant mucoid material
  1. Treatment
    * Marginal excision
  2. Associated conditions
  • Mazabraud syndrome
    • Multiple intramuscular myxomas in same general area as fibrous dysplasia
71
Q

Desmoid Tumour

Classification

Age

Presentation

Location

Imaging

Histology

Treatment

Assoc Conditions

A
  1. Classification - Benign (Fibrous)
    * Locally invasive
  2. Age = 15-40
  3. Presentation
  • Painless mass
  • Hard, fixed and deep
  1. Location
  • >50% are extra-abdominal = shoulder, chest, back, thigh
  • <50% are intra-abdominal = pelvis, mesentery
  1. Imaging
  • MRI = T1 - low signal
    • T2 = low-medium signal
    • Infiltrative within muscle
    • Usually 5-10cm in size
    • Enhances with gadolinium
  1. Histology
  • Bland fibroblasts with abundant collagen
  • No tumour capsule, often infiltrates into adjacent tissue
  1. Treatment
  • Wide surgical resection
    • Indicated if resectable
    • Adjuvant radiation (high risk of recurrence)
  • Chemotherapy/tamoxifen
    • Reserved for inoperable lesions
  1. Associated conditions
  • Dupuytrens
  • Ledderhose disease (plantar fibromatoses)
  • Gardener syndrome
  • Familial adenomatous polyposis
72
Q

Synovial Chondromatosis

Classification

Age

Presentation

Location

Imaging

Histology

Treatment

A
  1. Classification - Benign (Synovial)
  2. Age = 30-50
  3. Presentation
  • Pain, clicking, decreased ROM
  • Warmth, erythema, tenderness depending on joint
  • Slow progression of symptoms
  1. Location
  • Most common = hip and knee
    • Also shoulder and elbow
  1. Imaging
  • Radiographs = variable depending on stage (not visible initially until calcify)
    • Stippled calcification
  • MRI = lobular appearance
  1. Histology
  • Gross = hundreds of osteocartilaginous loose bodies
  • Nodules are hyaline cartilage
    • Chondrocytes have mild atypia
  1. Treatment
  • Observation = Mild symptoms
  • Open or arthroscopic synovectomy = symptomatic
    • May help prevent degenerative changes
73
Q

Pigmented Villonodular Synovitis (PVNS)

Classification

Age

Presentation

Location

Imaging

Histology

Treatment

A
  1. Classification - Benign (synovial)
  2. Age = 30-50
  3. Presentation
  • Recurrent atraumatic hemarthrosis = hallmark
  • Diffuse form = pain, swelling, effusion, erythema, decreased ROM
  • Focal form = mechanical symptoms
  • Extra-articular form
    • Giant cell tumour of tendon sheath
    • = small, painless, superficial soft-tissue nodule
  1. Location
  • Most common = knee (80%)
    • Also hip, shoulder, ankle
  • Extra-articular form = giant cell tumour of tendon sheath
    • Most common = hand/wrist
  1. Imaging
  • Radiographs = may show cystic erosions on either side of joint with sclerosis
  • MRI = T1 and T2 - low signal intensity
    • “Blooming artifact”
      • Signal loss on gradient echo sequences
    • May show extra-articular extension
  1. Histology
  • Gross = frond-like papillary projections
  • Mononuclear stromal cell infiltrate within the synovium
  • Hemosiderin-laden macrophages and multinucleated giant cells
  1. Treatment
  • Arthroscopic and open synovectomy
    • Indicated in symptomatic disease
  • Marginal excision
    • Indicated in giant cell tumour of tendon sheath
  • TKA
    • Indicated in advanced disease with secondary degeneration
  • Radiation
    • Reserved for multiple recurrences
74
Q

Myositis Ossificans

Classification

Age

Presentation

Location

Imaging

Histology

Treatment

A
  1. Classification - Benign (reactive)
  2. Age = 15-35
  3. Presentation
  • Pain, tenderness, swelling, decreased ROM after injury
    • Followed by mass increasing in size over several months then growth stops and becomes firm
  1. Location
    * Most common = quadriceps, brachialis, gluteal
  2. Imaging
  • Radiographs = initially, irregular, fluffy densities in the soft tissue
    • Followed by peripheral mineralization and radiolucent centre
  • MRI = rim enhancement with gadolinium seen within first 3 weeks
  • CT = defines ossified lesion, looks like an egg-shell
  1. Histology
  • Periphery = mature lamellar bone
  • Intermediate = poorly defined trabeculae with osteoblasts, fibroblasts and mitoses
  • Centre = immature, loose, fibrous tissue
  1. Treatment
  • Observation
    • Self limited process
    • Size decreases after 1 year
  • Surgical excision
    • Indicated only after mature (~6-12 months) and symptomatic
75
Q

Soft Tissue Sarcomas

Classification

Age

Presentation

Location

Imaging

Histology

Staging

Treatment

Prognosis

A
  1. Classification - Malignant
    * Hetergenous group of >50 types which behave in a similar fashion according to their size, location and grade
  2. Age = >15 (80%)
  3. Presentation
  • Painless enlarging mass
  • Nontender, firm, well-circumscribed
  • Constitutional symptoms and lymphadenopathy are uncommon
  1. Location
  • Most common = extremities (60%)
  • Mets = most commonly lung
  1. Imaging
  • Radiographs = generally nonspecific and nondiagnostic
  • MRI = enhance with gadolinium, usually respect fascial boundaries
  • CXR and CT chest = required for staging
  • CT chest/abdo/pelvis and Bone scan = for myxoid liposarcoma
  1. Histology
  • Core needle biopsy required for indeterminate lesions
    • Indetermine lesion = MRI cannot diagnose
    • Determinate lesion = MRI diagnostic
      • Includes lipomas, hemangiomas, ganglion and synovial cysts, myositis ossificans, and PVNS
  • Grow in a centripital fashion surrounded by a pseudocapsule
    • ‘Pushing tumor’ rather than ‘infiltrating tumor’
  • Appearance depends on type of sarcoma
    7. Staging
  • AJCC (American Joint Committee on Cancer)
    • Primary tumour (T)
      • TX – primary tumour cannot be assessed
      • T0 – no evidence of primary tumour
      • T1 - <5cm
        • T1a – superficial
        • T1b – deep
      • T2 - >5cm
        • T2a – superficial
        • T2b – deep
    • Regional lymph nodes (N)
      • NX – cannot be assessed
      • N0 – no lymph node mets
      • N1 – lymph node mets
    • Distant metastasis (M)
      • M0 – no distant mets
      • M1 – distant mets
    • Histological grade (G)
      • G1 – well differentiated
      • G2 – moderately well differentiated
      • G3 – poorly differentiated
      • G4 – dedifferentiated
        8. Treatment
  • Wide surgical resection with cuff of normal tissue (>1cm)
  • Radiation
    • Pre-operative – lower dose (~50Gy) over ~5 weeks with surgery ~4 weeks after completion
      • Higher wound complication (35% vs. 17%)
    • Post-operative – higher dose (~66Gy)
      • More fibrosis and joint contractures
  • Chemotherapy
    • Reserved for high grade, large tumours and mets
    • 3 soft tissue sarcomas are chemo sensitive:
      • Embryonal rhabdomyosarcoma
      • Ewing’s soft tissue sarcoma of bone
      • (synovial sarcoma)
  • Surgical resection of lung mets
    9. Prognosis
  • Low grade = 90% 5 year survival
  • High grade = 50% 5 year survival
  • Metastasis = 15% 5 year survival
  • Poor prognostic factors:
    • Masses >5cm
    • Masses deep to fascia
    • Histologic high-grade
    • Malignant tumor ulceration
    • Radiation-induced STS
    • Bony invasion
    • Older patient age
    • Lymph node involvement and mets
    • Positive margins
      • Risk factor for local recurrence but not shown to affect survival
76
Q

What sarcomas can metastasize to the lymph nodes?

A

SCARE

  • Synovial sarcoma
  • Clear cell sarcoma
  • Angiosarcoma
  • Rhabdomyosarcoma
  • Epitheloid sarcoma
77
Q

Undifferentiated Pleomorphic Sarcoma (UPS) of soft tissue

Classification

Age

Presentation

Location

Imaging

Histology

Treatment

A
  1. Classification - Malignant (fibrogenic)
    * Previously MFH - Malignant Fibrous Histiocytoma
  2. Age - 30-80
    * Most common soft tissue sarcoma in adults 55-80
  3. Presentation
    * Most common = slow growing, painless mass
    • May present with fever
      * May have history of trauma that draws attention to the mass
      * Painless soft tissue mass may be palpable
  • Lack of ecchymosis suggests an encapsulated mass
    • Differentiates from hematoma, which typically presents with ecchymosis after trauma
  • Neurovascular
    • Mass effect may cause neurovascular symptoms
  1. Location
    * Lower > upper extremities > retroperitoneum
  2. Imaging
  • MRI = T1 - low signal intensity (isointense with muscle)
    • T2 - high signal intensity
  1. Histology
  • Gross
    • Nodular, gray-white
  • 3 subtypes
    • Pleomorphic (80-85%)
    • Giant cell (10%)
    • Inflammatory (<10%)
  • Spindled, histiocytic, and multinucleated eosinophilic giant cells
  • Cells arranged in storiform (cartwheel) pattern arranged around small vessels
  • Atypia and mitoses present
  1. Treatment
  • Wide surgical resection & radiation therapy
    • Standard of care in most cases
    • Radiation is an important adjunct to surgery decreasing local recurrence
      • 50 Gy pre-op and 66 Gy postop is standard dose for soft-tissue sarcomas
    • Chemotherapy may be administered in some cases
    • 50-60% 5-year survival
  • Amputation
    • Indication
      • If unable to resect tumor with negative margins
      • Resection would result in irreversible damage to major nerves
      • Patient comorbidities limit potential for recovery after limb-sparing surgery
    • Good prognosis in absence of metastatic disease
78
Q

Liposarcoma

Classification

Subtypes

Imaging

Histology

Genetics

Treatment

A
  1. Classification - Malignant (fat)
    * 2nd most common soft tissue tumour (behind UPS)
  2. Subtypes
  • Dedifferentiated liposarcoma
    • Result of malignant transformation of ALT/WDL
    • 18% of liposarcomas
  • Myxoid liposarcoma
    • Continuum from low-grade well-differentiated myxoid tumours to high grade poorly differentiated round cell tumours
    • <20% of liposarcomas
    • Most common in lower extremity
      • 2/3 in deep thigh
    • Can metastasize to sites other than lung including retroperitoneum (mets to fat)
    • CT chest/abdo/pelvics required for staging
  • Pleomorphic liposarcoma
    • 5-15% of liposarcomas
    • Older patients (>60)
    • 2/3 in extremities
      • Most deep to fascia, 25% subcutaneous
  1. Imaging
    * MRI
    • Heterogeneous
    • T1 = hypointense
    • T2 = hyperintense
    • Post-gad = heterogeneous enhancement
      * CT Chest
    • To assess for lung mets
    • Myxoid liposarcoma requires CT C/A/P
  2. Histology
  • Dedifferentiated
    • Discrete areas similar to UPS/fibrosarcoma adjacent to ALT/WDL
  • Myxoid
    • Lipoblasts within myxoid stroma
      • Lipoblast (signet ring-type cell) is a hallmark of liposarcomas
  • Pleomorphic
    • Lipoblasts in background of high-grade pleomorphic sarcoma
      • Lipoblasts differentiate from UPS
  1. Genetics
  • Dedifferentiated = MDM2 and CDK4 amplification
  • Myxoid = t(12;16) translocation –> FUS-DDIT3(CHOP)
  1. Treatment
  • Well differentiated = marginal resection
  • Intermediate and high grade = treat as soft tissue sarcoma
    • Wide surgical resection with cuff of normal tissue (>1cm)
    • Radiation - Pre (~50Gy) or postop (~66Gy)
    • Chemotherapy for high grade, large tumours and mets
  • Myxoid
    • Responsive to chemo and radiation
      • Especially if high round cell component
      • Particularly useful in reducing tumour size
  1. Prognosis
  • Dedifferentiated
    • Local recurrence >40%
      • ~100% in retroperitoneum
    • Distant mets in 15-20%
      • Most common = lungs, then liver
    • 5y mortality = 30%
    • Anatomic location best predictory of outcome
      • Retroperitoneal is the worst
  • Myxoid
    • Depends on % of high grade/round cell component
    • Low grade has <10% metastatic risk
    • High grade has <35% metastatic risk and mortality rate
      • Poor prognostic factors
        • >10cm
        • >25% round cell component
        • Age>45
        • Spontaneous necrosis
  • Pleomorphic
    • Metastatic rate <50%
    • 5y survival = 60%
    • Superficial tumours have better prognosis
      • Local recurrence <10%
      • 0% mets
    • Poor prognostic factors
      • Large
      • Retroperitoneal
      • Older patient
79
Q

Fibrosarcoma (of soft tissue)

Classification

Age

Presentation

Imaging

Histology

Treatment

A
  1. Classification - Malignant (fibrogenic)
    * Same as MFH - Malignant Fibrous Histiocytoma
  2. Age - 30-80
  3. Presentation
  • Most common = slow growing, painless mass
    • Symptomatic when >10cm
  1. Imaging
    * MRI = deep seated inhomogeneous mass
  2. Histology
    * Fasiculated growth pattern
    * Spindle-shaped cells with scant cytoplasm and indistinct borders
    * Cells separated by interwoven collagen fibers
    * Tissue may be organized in herringbone fashion
  3. Treatment
    * wide local resection with perioperative radiation

indications

* Add radiation if tumor is \> 5 cm (5000 cGy before resection and 2000 cGy after resection) * Local adjuvant treatment
* Phenol or cryotherapy
80
Q

Dermatofibrosarcoma Protuberans

Classification

Age

Presentation

Location

Imaging

Histology

Genetics

Treatment

A
  1. Classification - Malignant (fibrogenic cutaneous)
  2. Age - 20-50
  3. Presentation
  • Most common = slow growing, painless mass
    • Composed of firm irregular nodules
    • May have dark red or blue discoloration
      1. Location
  • Trunk > proximal extremities > head/neck
    5. Imaging
  • Radiographs
    • CXR to screen for lung mets in high-risk cases
      • i.e. recurrence or suspicion for a fibrosarcoma variant of DFSP
  • MRI
    • Preop assessment in larger or atypical lesions and recurrent disease
  • Ultrasound
    • ​Monitoring of local DFSP or regional lymph node metastasis
  • PET
    • Monitoring of metastatic disease
      1. Histology
  • Biopsy required for diagnosis
  • Classically = uniform fibroblasts arranged in storiform pattern around an inconspicuous vasculature
    • Bednar variant has scattered melanin-containing dendritic cells
  • Fibrosarcomatous variant has a characteristic herringbone pattern
    7. Genetics
  • Mutations associated with t(17;22)
    • Encodes for PDGF-beta chain (PDGFB)/collagen type I alpha 1 (COL1A1) fusion protein
  1. Treatment
  • Imatinib
    • 65% response rate
      • No response in patients who lack the t(17,22) mutation
    • Indicated in adult patients with unresectable, recurrent, and/or metastatic DFSP
    • Inhibits PDGF-receptor tyrosine kinase
  • Wide surgical resection +/- adjuvant radiation therapy
    • Adjuvant radiation therapy is useful in patients with positive margins or in whom adequate wide excision alone may result in major cosmetic or functional deficits
    • 15.7% recurrence for lesions on the body
    • 51.8% recurrence rate for lesions on the head/neck
  1. Prognosis
  • Local recurrence is common
  • Distant metastasis is rare (< 5%)
    • Lung is the most common site
    • Occurs via hematogenous spread
    • Usually preceded by multiple local recurrences
  • Worse prognosis:
    • Regional lymph node involvement
    • Fibrosarcomatous progression DFSP variant
    • Histologic features: high number of mitotic figures, increased cellularity, DNA aneuploidy, TP53 gene overexpression, and the presence of fibrosarcomatous changes
    • Age > 50 years old
81
Q

Synovial Sarcoma

Classification

Age

Presentation

Location

Imaging

Histology

Genetics

Treatment

A
  1. Classification - Malignant
    * Unknown origin - not synovial
  2. Age = 15-40
  3. Presentation
    * Slow growing mass, 50% have pain
  4. Location
  • Arises near joints but rarely involves a joint
  • Most common = knee, shoulder, arm, elbow, foot
    • Most common malignant sarcoma of the foot
  • Can metastasize to regional lymph nodes
    • Lung mets still more common
  1. Imaging
  • Radiographs = calcification in ~20%
  • MRI = indeterminate
    • T1 = low signal
    • T2 = high signal
  1. Histology
  • Biphasic appearance with two cell types
    • Spindle cells
    • Epithelial cells
  1. Genetics
  • t(X;18) chromosomal translocation
  • SYT-SSX1, 2, or 4 fusion protein
  1. Treatment
  • Same as soft tissue sarcoma
    • Wide surgical resection with cuff of normal tissue (>1cm)
    • Radiation - Pre (~50Gy) or postop (~66Gy)
    • Chemotherapy for high grade, large tumours and mets
82
Q

Epithelioid Sarcoma

A
  • Most common soft tissue sarcoma of the hand/wrist
  • CA125 highly expressed in tumour
  • Firm, painless nodule often confused with RA nodule, granuloma, or skin cancer
83
Q

Clear Cell Sarcoma

AKA Malignant melanoma of skin

A

Has ability to produce melanin

84
Q

Rhabdomyosarcoma

Classification

Subtypes

Histology

Treatment

A
  1. Classification - Malignant (mesenchymal)
    * Most common soft tissue sarcoma in children
  2. 4 subtypes
  • Embryonal – occurs in infants and young children
  • Alveolar – occurs in adolescents and young adults
    • t(2;13) translocation
  • Botryoid – occurs in infants and young children
  • Pleomorphic – occurs in adults (40-70)
  1. Histology
    * Immunohistochemistry postive for desmin, myoglobin, MyoD1
  2. Treatment
  • Pleomorphic = as for soft tissue sarcoma
    • Wide surgical resection with cuff of normal tissue (>1cm)
    • Radiation - Pre (~50Gy) or postop (~66Gy)
    • Chemotherapy for high grade, large tumours and mets
  • Pediatric rhabdomyosarcoma = chemotherapy and wide surgical excision
85
Q

Malignant Peripheral Nerve Sheath Tumour

A

• 50% associated with NF-1

  • Patients with NF-1 have 5% risk of malignant transformation

• Treat as soft tissue sarcoma

  • Wide surgical resection with cuff of normal tissue (>1cm)
  • Radiation - Pre (~50Gy) or postop (~66Gy)
  • Chemotherapy for high grade, large tumours and mets
86
Q

Melorheostosis

Classification

Age

Presentation

Location

Imaging

Treatment

A
  1. Classification - Benign (Bone/periosteum)
  2. Age = presents before age 40
  3. Presentation
  • Pain, decreased ROM, contractures
  • Fibrosis of skin common with tense, erythematous, indurated skin
  1. Location
    * Most common = lower extremities
  2. Imaging
  • Radiographs = cortical hyperostosis
    • ‘Dripping candle wax appearance’
    • May flow across joints
  1. Treatment
  • Analgesics
  • Hyperostotic bone resection with contracture release
    • Reserved for severe contractures, limited mobility, and pain
87
Q

Neurofibroma

Classification

Population

Presentation

Imaging

Genetics

Treatment

DDx

A
  1. Classification - Benign peripheral nerve sheath tumour
  2. Population - Patients with NF
  3. Presentation
  • May be painful
  • Firm, possibly tender
    • Tinel’s sign at mass
  • Mobile in transverse plane but not longitudinal plane
  1. Imaging
  • MRI
    • Enhancing heterogeneous lesion
    • Target sign on T2
      • Circumferential high signal (myxoid) around centre of low signal (nerve fibres)
    • Serial MRI used for monitoring for degeneration to malignancy
    • To differentiate from Schwannoma:
      • Schwannoma are eccentric to nerve fibres
      • Solitary neurofibromas are central to nerve fibres
  1. Genetics
  • Associated with inactivation of NF1 tumor suppressor gene (17q11.2)
  • Loss of expression of protein neurofibromin
  • Neurofibromin negatively regulates RAS-mediated pathway
  • Loss of neurofibromin leads to increased RAS activity
  • Affects RAS-dependent MAPK activity which is essential for osteoclast function and survival
  • Rapid hyperplasia of nonmyelinating Schwann cells into neurofibromas after NF1 inactivation
    • Recruits perineural cells, fibroblasts, mast cells, endothelial cells
  1. Treatment
  • Observe if asymptomatic
  • Surgical resection if symptomatic
    • May require nerve grafting
  1. DDx
  • MPNST (malignant peripheral nerve sheath tumor or neurofibrosarcoma)
    • 5% of patients with NF, 10-25% lifetime risk
    • Symptoms include painful, enlarging soft tissue mass
    • Usually from plexiform neurofibroma
      • 10% of plexiform neurofibromas transform into MPNST
    • Associated with loss of expression of CDKN2A or TP53 genes in non-myelinating Schwann cells (that also have biallelic inactivation of NF1)
    • Poor prognosis
      • Widespread metastasis
      • High rate of local recurrence
88
Q

What are the associated translocations?

Myxoid Lipsarcoma

Ewing Sarcoma

Synovial Sarcoma

Myxoid Chondrosarcoma

Rhabdomyosarcoma

89
Q

What are the associated stains?

Langerhans cell histiocystosis

Lymphoma

Ewing Sarcoma

Chordoma

Myeloma

Adamantinoma

0. Harty (30 decks)

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