Bone Tumors Flashcards
What are the 4 things that you should be aware of for bone tumors to make the dx easier?
- age 2. sex 3. location 4. radiologic appearance of lesion
What is fibrous dysplasia?
benign, localized developmental arrest, no maturity of bone even though bone is present * 3 patterns - polyostotic, monostotic and McCure Albright Syndrome (poly)
What is McCure Albright syndrome?
cafe au lait skin pigmentation, endocrinpathies associated w/ this
What does histo for fibrous dysplasia look like?
- loose whorled pattern of fibroblastic tissue w/ irregular spicules of woven bone. 2. small islands of cartilage, chinese characters, poorly formed islets of bone. 3. Can undergo cystic degeneration.
x-ray for fibrous dysplasia?
large expansile, apparently medullary mass with a somewhat moth-eaten appearance adjacent to it
What is fibrous cortical defect?
- Eccentric, sharply delineated, metaphyseal lesion in long bones of adolescents
- usually occurs at metaphysis of femur and proximal tibia.
- Spontaneously resolves.
- 1/2 are bilateral or multiple, seen incidentally on xrays
What is the appearance of fibrous cortical defect?
- scooped out appearance w/ sclerotic margin.
What is a nonossiffying fibroma?
a large fibrous cortical defect (> 5/6 cm)
What is characteristic of nonossifying fibroma?
woven mat or storiform pattern
What are solitary bone cysts?
- benign fluid filled cysts
- thin, lytic bone lesions in males
- humerus/femur
- asymtompatic
- large lesion can lead to a fracture
What are aneurysmal bone cysts?
- bloody, cystic lesions
- usually in long bones/vertebral column,
- lesion is from the surface of the bone
- slow growing but can rapidly expand
This is aneurysmal bone cyst. What can be found in microscopic pathology?
- clotted blood
- giant cells – dont’ misDx giant cell tumor or TB
Tell me about benign bone neoplasms
- happens in 1st 3 decades in life mostly
- found on incidental xrays
- rarely undergo malignant transformation EXCEPT CHONDROMA
- usually removed only if cause pain
- examples : Osteoma, osteoid osteoma, osteochrondroma/chondroma, fibroma, giant cell tumor
What is an osteoma?
- round, projects from sub/endosteal surface of cortex
- slow growing
- usually solitary, mutiple seen in Gardner’s syndrome
What is osteoid osteoma?
- one of the more common representations of osteoma
- generally less than 2 cm
- teens/20’s – MALES
- 50% - in tibia/fibula
What is a primary characteristic of osteoid osteoma?
- Painful due to lesion making PGE2
- pain is more common at night, relieved by aspirin and alcohol
What is osteochrondroma?
- also known as exostosis
- cartilage capped tumor – attached to underlying skeleton by stalk
- grows proximally to epiphyseal plate
What is osteochrondoma due to?
- displacement of growth plate in endochrondal bones
- you can have a multiple hereditary exotosis which is AD and can give rise to chondrosarcoma
What is a chrondroma?
- hyaline cartilage tumor
What are the 2 types of chrondromas?
- endochrondroma - arises in medullary cavity
- juxtacortical - arises on surface of bones
Where is an endochrondroma usually found?
- Metaphyses of tubular bones: hands/feet – usually solitary
- here is a pic of a phalanx - radiolucent nodules of hyaline cartilage scalloped endosteal surface
What is it called when endochrondromas present w/ mutiple lesions?
- Ollier dz - nonhereditary syndrome
- Muffucci Syndrome - multiple enchondromas form as well as soft tissue hemangiomas
What is Giant Cell Tumor of Bone?
- multinucleated osteoclast type giant cells that are locally aggressive
- cystic degeneration
where is giant cell tumor of bone normally found?
in knee than bones of wrist.
* here is a pic of a soft, hazy neoplasm which appears to be destroying the distal femur
tell me about malignant bone tumors
- rare
- 50% from blood forming cells and CT cells
- Mets are more common than primary bone tumors
What is most common primary malignant bone tumor and where is it found in the body?
Osteosarcoma – in knee
* smaller peak of these in the elderly, in patients who have Paget disease of bone
What is 2nd most common primary malignant bone tumor and where is it found in the body?
chrondrosarcoma – trunk and limb girdles
What else has osteosarcoma been associated with?
- Retinoblastoma
- 20% have lung mets at time of dx
- Painful, progressively enlarging; fracture
What is seen microscopically in osteosarcoma?
poorly formed bone spicules in between which is a cellular matrix with osteoid and malignant cells
What is characteristic of an osteosarcoma? — BOARD QUESTION!
periosteal elevation on x-ray = Codman’s triangle
What is chondrosarcoma?
- occur in the axial skeleton, characteristically in the trunk, pelvis, vertebrae and ribs
- May arise in association with preexisting enchondroma
- 35-60
- Rx = SURGERY
What is characteristic of malignant bone tumor?
bulk of tumor is distal and some is proximal meaning that it doesn’t respect the joint spaces
This is a chondrosarcoma - what do the cells look like at this level and what would they look like at a higher power?
- cellular neoplasm - mimic chondrocytes
- at higher power - look like malignant cells w/ high N:C ratio, nuclei, and mitotic figures
What is Ewing Sarcoma?
- small, round blue cell tumor
- 10-15 yr, white
- arise in medulla of bone - diaphysis of long joints
- good prognosis - srugery and chemo!
What cancer is this and what are you supposed to see in these cells?
- Ewing Sarcoma
- glycogen rich
- Homer-Wright Rosettes - tumor cells arranged in a circle about a central fibrillary space – possibly neural differentiation
What do you see on xray for Ewing sarcoma – also what is the translocation?
- onion skin – layers of reactive perisoteum
- 11;22
Tell me about bone Met tumors
- Adults > 75% of skeletal metastasis originate from prostate, breast, lung, and kidney
• Kids: neuroblastoma, Wilms’ tumor, osteosarcoma, Ewing sarcoma (extraosseous) and rhabdomyosarcoma
• Usually multifocal: vertebrae, pelvis, ribs, skull and sternum (marrow-rich areas)
• XR: lytic, blastic or mixed lytic and blastic
• Secrete substances that promote bone resorption
