Tumour Flashcards
What lesion is improved with ibuprofen?
Osteoid osteoma
Describe Mirel’s criteria. What is it used for?
Score for prophylactic fixation of pathological fractures Score: 8 or more indicated prophylactic fixation - Site 1: upper limb 2: lower limb 3: peritrochanteric - Lesion: 1: blastic 2: mixed 3: lytic - Size of lesion: 1: 2/3 - Pain: 1: mild 2: moderate 3: severe
What is the clinical vignette of a patient with Osteoid osteoma?
Young patient with pain totally relieved by NSAIDs.
Pain worse at night
May spontaneously resolve in 2-4 years
What levels are increased in Osteoid osteoma?
Cox 1 & 2
Islands of epithelial cells in a spindle-cell stroma +/- nuclear atypia with mitotic figures
Adamantinoma
Loose, storiform fibrous background containing spicules of woven bony trabeculae that are lined with layers of osteoblasts
Osteofibrous dysplasia
What is typical of an osteoid osteoma radiograph?
A nidus of bone
Slowly enlarging, painless soft tissue mass. what are you worried about?
Soft-tissue sarcoma
A mutation in which gene causes multiple hereditary exostosis?
EXT1 & EXT2
“Stuck on” appearance:
parosteal osteosarcoma
A genetic abnormality in the cyclic AMP signaling pathway:
Fibrous dysplasia
Life expectancy of bone mets, from Best to Worst
The Pit Bulls Keep Laughing:
Thyroid, Prostate, Breast, Kidney, Lung
What percentage of Paget’s disease transforms into osteosarcoma?
1%
What are the 5 most common primary sites of metastatic bone lesions?
Thyroid, prostate, breast, kidney, lung
Prostate bony mets: Lytic of blastic?
Blastic
Name 3 lytic mets:
Renal, lung, thyroid
What are the requisite steps of bony metastasis?
- Tumor cell intravasation (entry into blood vessels)
- Avoidance of immune surveillance
- Target tissue localization,
- Induction of angiogenesis
What percentage of enchondromas transform into chondrosarcoma?
<1%
What sarcoma’s to go the LNs?
RACES: (RACES to the LN) Rhabdomyosarcoma Angiosarcoma (vascular) Clear cell sarcoma Epithelioid sarcoma Synovial sarcoma
Is sending reamings a good option for biopsy? Why or why not?
No, because reamings could contaminate adjacent tissue (muscle, fat, additional compartments), risking successful limb salvage if bx comes back + for malignancy (b/c you’ve just spread it).
NO definitive treatment until biopsy is back.
What is the constellation of signs and symptoms of multiple myeloma?
CRAB
- Calcinosis
- Renal dysfunction (increased Cr)
- Anemia
- Bony (lytic) lesions
What are the tumor biopsy principles?
- Longitudinal incision (allows for extension of incision during definitive management)
- Do not expose neurovascular structures
- Maintain meticulous hemostasis
- Approach through affected compartment
- Can biopsy adjacent soft tissue if its an extension of the bony tumor
- Insert any drains in line with the wound
What tumors should be biopsied?
All
What does post-operative radiation achieve?
Pain reduction
Slowing of progression
Reduction in tumor burden
What laboratory test should be ordered in the setting of osteosarcoma?
ALP
- Can be increased 2-3x
What is the risk of malignant transformation of multiple hereditary exostosis (MHE)? What does it transform to?
5-10% risk of transformation to chondrosarcoma
What is Maffuci syndrome?
Variant of enchodroma:
Multiple enchondromatosis
Hemangioma/angioma
Lymphangioma
Visceral malignancy (brain - astrocytoma, GI)
High risk of transformation to chondrosarcoma
What is the Enneking tumour staging system?
Benign: 1: Latent 2: Active 3: Aggressive Malignant: I: Low grade, no mets: - IA: intracompartmental - IB: extracompartmental II: High grade, no mets: - IIA: intracompartmental - IIB: extracompartmental III: Metastatic - IIIA: intracompartmental - IIIB: extracompartmental
What is the AJCC tumour staging system?
American Joint Committee on Cancer System
What works better on osteosarcoma? Radiation or chemotherapy?
Chemotherapy
- Osteosarcoma is highly resistant to radiation therapy
What are the absolute and relative contraindications for limb-salvage surgery?
- Inability to obtain a wide surgical margin
- Neurovascular involvement
- Pathologic fracture
What is the survival rate for non-metastatic and metastatic osteosarcoma?
10 year survival:
Non-metastatic: 60-80%
Metastatic: 20-30%
What effect of chemo has been reported to improve survival?
> 90% tumor necrosis with neoadjuvant chemotherapy
What are the types of osteosarcoma?
Intramedullary: - Conventional: most common - Telangeictatic - Low grade - Small-cell Surface: - Parosteal - low-grade - Periosteal - intermediate grade - High-grade - high grade
Describe conventional osteosarcoma?
Intramedullary osteosarcoma
Most common variant (80%)
X-ray: Osteolytic and/or blastic bone lesion with cortical destruction
Histo:
- Malignant mesenchymal cells
- Spindle to polyhedral shape
- Pleomorphic nuclei and occasional mitotic figures
- Evidence to bone or osteoid matrix
Further divided into:
- Osteoblastic, chondroblastic, fibroblastic, depending on matrix
Describe Telangiectatic osteosarcoma?
Intramedullary osteosarcoma
Eccentric and osteolytic lesion expanding or disrupting the metaphyseal surface
- Lesion may resemble an ABC as it contains multiple blood-filled sinusoids
- High signal intensity on T2- weighted MRI
Histo:
- Multiple dilated hemorrhagic cavities, small amounts of osteoid and high grade osteosarcoma cells found within the septa
Describe low-grade intramedullary osteosarcoma
Intramedullary osteosarcoma
- Unaggressive appearing lytic, mixed lytic/blastic or blastic process
- Appears fibro-osseous
- Varying amouts of septal ossification and sclerosis
Histo:
- Well-differentiated cells dispersed with women microtrabeculae of bone and fibrous stroma
- Small amounts of osteoid, atypia and mitotic figures
Describe small-cell osteosarcoma
Intramedullary. Rare
- Lytic areas with variable amounts of sclerosis
- MRI: large circumferential soft-tissue mass
Histo:
- Small, round, malignant cells within an osteoid matrix
Describe parosteal osteosarcoma:
Surface osteosarcoma
- Densely ossified and lobulated mass sparing IM cavity
- Often posterior on femur
Histo:
- low-grade, well differentiated fibrous stroma with osseous components
- “Pulled steel wool” pattern with presence of bony trabeculae with a parallel orientation
Describe periosteal osteosarcoma:
Surface juxtacortical tuour
- More aggressive than parosteal
- Lytic, radiolucent mass sparing IM cavity
- Sunburst appearance common
Histo:
- Intermediate grade tumour containing cartilagenous matrix with areas of calcification
- Small amounts of osteoid
Describe high grade osteosarcoma:
- Surface osteosarcoma with partial mineralization and tumour extension in surrounding ST
Histo: - High grade spindle cells with atypia and varying amounts of osteoid
What is the common origin of the Ewing Sarcoma Family of Tumours?
Mesenchymal stem cells capable of differentiation into multiple lineages
Describe Ewing’s Sarcoma
Ill-defined, mottled or focally moth-eaten destructive intramedullary lesion. Laminated or onionskin peristeal reaction. May have sunburst or codman’s triangle
What are the differences between Osteosarcoma & Ewing’s sarcoma?
Osteosarcoma: Metaphysis
ES: diaphysis/metadiaphyseal
Osteosarcoma: Codman’s triangle/sunburst more common
Both 2nd decade of life
What is the common genetic abnormality in Ewing’s?
EWS-ETS (FLI1) fusion gene
11;22 translocation
Describe the histopathology of de-differentiated chondrosarcoma:
Often not of the same type as the primary chondrsarcoma/osteochondroma (ie it’s something else like osteosarcoma)
What part of the osteochondroma becomes malignant in secondary chondrosarcoma?
The cartilagenous cap
dDx for “Bubbly” or “Soap bubble” appearance on x-ray
aneurysmal bone cyst (ABC)
non-ossifying fibrooma (NOF)
unicameral bone cyst (UBC)
“metaphyseal eccentric “bubbly” lytic lesion surrounded by sclerotic rim”
Non-ossifying fibroma
What is MHE?
Multiple hereditary exostosis. Multiple osteochondromas
Maliganancy risk: 5-10% with MHE (vs. 1% with solitary osteochondroma)
EXT gene
multiple hereditary exostosis
What is the risk of malignancy for solitary osteochondroma & MHE
Risk of transformation into chondrosarc:
1% for solitary
5-10% for MHE
Ollier’s & Maffuci:
Multiple enchondromas:
Ollier’s: multiple enchondromatosis. 30% malignancy
Maffuci: 100% malignancy from enchondromatosis & angioMa and visceral malignancies (GIs)
What is the most malignant form of chondrosarcoma?
Dedifferentiated chondrosarcoma
What is the 10 year survival rate of dedifferentiated chondrosarcoma?
10% at 10 years - it is the most malignant form of chondrosarcoma
Risk factors for fracture in bone mets (not mirel’s)
Resistant tumour
Widespread disease
Visceral involvement
End stage disease
