SM_230a: Neoplasia Flashcards
Describe classification of major bone tumors
Classification of bone tumors
- Bone marrow: malignant (myeloma, malignant lymphoma)
- Bone: benign (osteoma, osteoid osteoma, osteoblastoma), malignant (osteosarcoma)
- Cartilage: benign (osteochondroma, chondroma, chondroblastoma, chondromyxoid fibroma), malignant (chondrosarcoma)

Describe histology of each bone component
Histology of each bone component
- Bone: pink dense connective tissue composed of osteocytes
- Bone marrow: adipocytes and adipose
- Cartilage: connective tissue w/ each chondrocyte in a lacuna

Describe bone tumors in general
Bone tumors
- Most commonly occur due to metastasis from other sites: usually osteolytic (punched-out lesion), prostate carcinoma is osteoblastic
- Most common primary bone tumors are multiple myeloma and osteosarcoma
- Primary bone tumors often more common in males (some exceptions like giant cell tumor)
- Histology comes last because bone can exhibit limited changes
Benign bone tumors are ____, ____, ____, ____, ____, ____, and ____
Benign bone tumors are osteoma, osteoid osteoma, osteoblastoma, osteochondroma, chondroma, giant cell tumor of bone, and fibrous dysplasia
Describe osteoma
Osteoma
- Benign solitary
- Middle age
- Most commonly arise on surface of facial bones
- Slow-growing, little significance unless blocks the sinus cavity
- Multiple osteomas associated with Gardner’s syndrome

Describe osteoid osteoma
Osteoid osteoma
- Small benign tumor of osteoblasts (< 2 cm)
- Young adults < 25, more common in males
- Nocturnal bone pain relieved by aspirin
- Cortex of long bones (femur)
- X-ray: zone of sclerotic lamellar bone surrounding a lucent focus (nidus): woven bone in vascular stroma
- Surgery or radiofrequency ablation
- Prognosis excellent (must remove nidus)

Osteoid osteoma is a _____ tumor of _____
Osteoid osteoma is a small benign tumor of osteoblasts (< 2cm)

Osteoid osteoma presents as _____ pain relieved by _____
Osteoid osteoma presents as nocturnal bone pain relieved by aspirin

Osteoid osteoma manifests as ____ on X-ray
Osteoid osteoma manifests as zone of sclerotic lamellar bone surrounding a lucent focus (nidus) on X-ray
(woven bone in lamellar stroma)

Osteoid osteoma is treated with ____ or ____
Osteoid osteoma is treated with surgeery or radiofrequency ablation

Describe the nidus in osteoid osteoma
Nidus in osteoid osteoma
- Radiolucent central focus of woven bone with a vascular stroma, surrounding cortical bone is thickened
- Anastomosing woven bone + osteoblastic rimming + vascular stroma

Contrast osteoblastoma and osteoid osteoma
Osteoblastoma and osteoid osteoma
- Tumors of osteoblasts
- Osteoid osteoma: < 2cm, long bone (femur), responds to NSAIDs
- Osteoblastoma: > 2 cm, vertebrae, does not respond to NSAIDs

Describe osteochondroma
Osteochondroma
- Most common benign bone tumor
- Male < 25, after fracture or radiation
- Bone + cartilaginous cap arise from metaphysis (growth plate)
- Distal femur, proximal tibia
- Prognosis: 1-2% recur, rarely can transform to chondrosarcoma

____ is the most common benign bone tumor
Osteochondroma is the most common benign bone tumor

Osteochondroma looks like an ___ on X-ray
Osteochondroma looks like an ice cream cone on X-ray

Osteochondroma has a _____ cap on a bony stalk continuous with the _____ of the bone
Osteochondroma has a cartilaginous cap on a bony stalk continuous with the medulla of the bone

Describe chondroma
Chondroma
- Benign intramedullary cartilaginous neoplasm
- 2nd-4th decades, males and females equally likely
- Medulla of small bones of hands and feet
- X-ray: well-circumscibed, lucent with cartilage matrix calcification (“arc and ring” due to enchondral bone formation at periphery of tumor nodule)
- Observation with serial radiographs, curettage (5% recurrence rate)

Chondroma occurs in the medulla of ____
Chondroma occurs in the medulla of small bones of hands and feet
Chondroma manifests as ______ on X-ray
Chondroma manifests as well-circumscribed lucent with cartilage matrix calcification (“arc and ring” due to enchondral bone formation at periphery of tumor nodule)
Chondroma is managed by ____ and ____
Chondroma is managed by observation with serial radiographs and curettage
Describe giant cell tumor of the bone
Giant cell tumor of the bone
- 20-40 years (skeletally mature), more common in females
- Epiphysis of long bone: most common in distal femur/proximal tibia (knee region)
- Radiograph: soap-bubble lytic lesion on epiphysis
- En bloc excision preferred
- Locally aggressive benign tumor
- May recur

Giant cell tumor of bone occurs more commonly in _____ than _____
Giant cell tumor of bone occurs more commonly in females than males
Giant cell tumor of the bone occurs most often in the ____
Giant cell tumor of the bone occurs most often in the knee region
(epiphysis of long bone: most common in distal femur/proximal tibia)
Giant cell tumor of the boan manifests as ____ on X-ray
Giant cell tumor of the boan manifests as soap-bubble lytic lesion in epiphysis

Giant cell tumor of the bone is treated with ______
Giant cell tumor of the bone is treated with en bloc excision
(locally aggressive benign tumor, may recur)
Describe fibrous dysplasia
Fibrous dysplasia
- Benign, linked to localized developmental arrest
- All normal component of bone present but they do not differentiate into mature structures
- Mostly in first three decades of life
- 3 patterns
- Single bone / monostotic (70%): femur most common
- Multiple bone (polyostotic): 27% w/o endocrine dysfunction, 3% w/ cafe-au-lait spots + endocrinopathy (McCune-Albright syndrome)

Fibrous dysplasia is linked to ____
Fibrous dysplasia is linked to developmental arrest
(all normal components present but do not differentiate into mature structures)
Describe the 3 patterns of fibrous dysplasia
Fibrous dysplasia patterns
- Signle bone (monostotic): 70%, femur most common
- Multiple bone (polyostotic): 27% w/o endocrine dysfunction, 3% w/ cafe-au-lait spots + endocrinopathy (McCune-Albright syndrome)
Summarize benign bone lesions
Benign bone lesions
- Osteoma: benign solitary, surface of facial bone, slow-growing, little clinical significance
- Osteoid osteoma: < 2cm long, long bone (femur), responds to NSAIDs
- Osteoblastoma: > 2 cm, vertebrae, does not respond to NSAIDs
- Osteochondroma: most common benign lesion, male < 25, bone + cartilage cap
- Chondroma: M=F, medulla of small bones of hands and feet
- Giant cell tumor of bone: F>M, epiphysis of long bones, soap-bubble
- Fibrous dysplasia: benign, linked to localized developmental arrest
Malignant bone tumors are ____, ____, and ____
Malignant bone tumors are osteosarcoma, chondrosarcoma, and Ewing sarcoma
Describe osteosarcoma
Osteosarcoma
- Malignant proliferation of osteoblasts
- Bimodal age: peak at 10-20 years and > 65 years
- Males: females is 3:2
- RF: familial retinoblastoma, Li-Fraumeni syndrome (germ line p53 mutation), Paget disease of the bone, bone infarct, radiation
- Metaphysis of long bones: usually distal femur / proximal tibia (knee) and proximal humerus
- Prognosis depends on preoperative chemotherapy

Osteosarcoma most commonly occurs in the ____
Osteosarcoma most commonly occurs in the distal femur / proximal tibia (knee)
(occurs in metaphysis of long bones so can also occur in proximal humerus)
Osteosarcoma manifests as _____ and _____ on X-ray
Osteosarcoma manifests as Codman triangle and sunburst reaction on X-ray
- Codman triangle: new subperiosteal bone that is created raises the periosteum away from bone
- Sunburst reaction due to periositis

Describe management of osteosarcoma
Osteosarcoma management
- >90% necrosis: continue chemo, local therapy if margins positive
- <90% necrosis: change chemo, local therapy if margins positive

Describe chondrosarcoma
Chondrosarcoma
- Peak in 5th-7th decades, M:F is 2:1
- Central portion of skeleton (pelvis, shoulder, rib)
- Most commonly central (within medullary cavity)
- Prognosis depends on grade and surgical adequacy
- Metastases are rare and occur late
(multiple nuclei in lacunae if low grade, very cellular w/ little matrix if high grade)

Chondrosarcoma occurs in the ______ portion of the skeleton
Chondrosarcoma occurs in the central portion of the skeleton (pelvis, shoulder, rib)
Chondrosarcoma manifests as _____, _____, and _____ on X-ray
Chondrosarcoma manifests as a lobulated lytic lesions with cartilage matrix calcification, cortical destruction, and no/minimal periosteal reaction

Describe Ewing sarcoma
Ewing sarcoma (primitive neuroectodermal tumor)
- Malignant neuroectodermal tumor of bone
- Characterized by t(11;22) creating fusion protein EWS-FLI1
- Most at < 20 years, M>F 2:1 (boys < 15)
- Diaphysis of long bones: most common in femur, then pelvis and ribs
- Treated with chemo (like osteosarcoma)
Prognosis: better if non-metastatic than if metastatic

Ewing sarcoma most often occurs in ____ that are ____ years old
Ewing sarcoma most often occurs in boys that are < 15 years old
Ewing sarcoma is characterized by ____, creating fusion protein ____
Ewing sarcoma is characterized by t(11;22), creating fusion protein EWS-FLI1
Ewing sarcoma most commonly occurs in _____
Ewing sarcoma most commonly occurs in femur
(diaphysis of long bones so also occurs in pelvis and ribs)
Ewing sarcoma manifests as _____, _____, _____, and _____ on X-ray
Ewing sarcoma manifests as poorly defined lytic lesion, cortical destruction, “onion skin”, and some soft tissue extension on X-ray

“Onion skin” on X-ray is indicative of the presence of _____
“Onion skin” on X-ray is indicative of the presence of Ewing sarcoma

Summarize malignant bone lesions
Malignant bone lesions
- Osteosarcoma: bimodal age (10-20 and > 65 years), prognosis depends on response to preoperative chemo
- Chondrosarcoma: peak in 5-7th decades, central portion of skeleton (pelvis, shoulder, rib), prognosis depends on grade and surgical adequacy
- Ewing sarcoma: malignant neuroectodermal tumor of bone, characterized by t(11;22) and fusion protein (EWS-FLI1), boys < 15, treated with chemo
Hematopoietic bone tumors are ____
Hematopoietic bone tumors are multiple myeloma
Describe multiple myeloma
Multiple myeloma
- Clonal proliferation of plasma cells (mostly IgG): kappa or lambda
- Most common primary malignant tumor of bone
- M>F, >40 years w/ peak in 65-70 years
- CRAB: C (hypercalcemia), R (renal insufficiency), A (anemia), B (lytic bone lesions)
- X-ray: multiple punched-out lytic lesions
- Location: vertebra, ribs, skull, pelvic bones, femur
- Treatment: chemo, individual lesion radiotherapy
- Prognosis is poor

Multiple myeloma is more common in ____ than ____
Multiple myeloma is more common in males than females
CRAB in multiple myeloma stands for ____, ____, ____, and ____
CRAB in multiple myeloma stands for hypercalcemia, renal insufficiency, anemia, and lytic bone lesions
Multiple myeloma occurs in the ____, ____, ____, ____, and ____
Multiple myeloma occurs in the vertebra, ribs, skull, pelvic bones, and femur
Multiple myeloma manifests as ____ on X-ray
Multiple myeloma manifests as multiple punched-out lytic lesions on X-ray

Prognosis for multiple myeloma is _____
Prognosis for multiple myeloma is poor
Summarize the locations of bone tumors
Locations of bone tumors
