Bone Tumors Flashcards
Bone mets
(a) single or multifocal
(b) axial or appendicular skeleton
(c) distal or proximal
(d) location on the bone
Bone mets
(a) typically multifocal- will often see mets elsewhere
(b,c) In the proximal axial skeleton- proximal femur and humerus
(d) often along the metaphyseal junction, white lesions interrupting the medullary cavity
Differentiate lytic vs. blastic lesions
Which type are
(a) prostate cancer mets
(b) thyroid cancer mets
Radiologic appearance
- lytic lesions = radiolucent (black)
- blastic lesions = radiodense (white)
(a) Prostate mets usually blastic (white)
(b) Thyroid mets usually lytic (white)
Where are the majority of bone mets from in adults? (3 places)
Prostate, breast, lung
Where are the majority of bone mets from in children?
Almost all are going to be neuroblastomas
-then minority will be Wilm’s tumor and osteosarcoma
Are most primary bone tumors benign or malignant?
Benign far outweigh the malignant
What are the three benign bone-forming tumors
(a) What type of bone do they form
3 benign bone-forming primary bone tumors = osteoma, osteoid osteoma, osteoblastoma
(a) produce osteoid- unmineralized bone
Which benign bone-forming tumor:
Is an exophytic mass usually growing out of the skull?
Osteoma
Which benign bone-forming tumor:
Cannot be distinguished from normal bone microscopically
Osteoma
Which benign bone-forming tumor:
Is treated by local excision
Osteoid osteoma and osteoblastomas both treated by local excision
-both as seen in young age ( F (2:1)
Which benign bone-forming tumor:
May be found with GI polyps and skin findings as part of a syndrome
Multiple osteomas + GI polyps + skin and soft tissue tumors = Gardner’s syndrome = autosomally dominant genetic syndrome
-if not as part of this syndrome osteomas are completely benign and clinically insignificant!
Osteoid ostoma vs. osteoblastoma
(a) Major distinguishing feature
(b) Most common location
(c) Type of pain
(d) Response to aspirin
Major distinguishing feature = size
Osteoid osteoma
(a) Less than 2 cm
(b) Appendicular skeleton
(c) Sharp nocturnal pain
(d) Relieved by aspirin
Osteoblastoma
(a) 2 cm, can be huge
(b) axial skeleton (vertebral column)
(c) Dull pain
(d) Not responsive to aspirin
Nidus
Histological characteristic of osteoid osteoma and osteoblastoma
-similar to woven bone but stroma is extra vascularized
How osteoblastomas differ histologically from osteosarcoma
Osteoblastomas = benign cytology and defined margins
(a) 1st
(b) 2nd
(c) 3rd
Most common primary bone cancers
Primary bone cancers, most common
(a) 1st = myeloma
(b) 2nd = osteosarcoma
(c) 3rd = chondrosarcoma
Osteosarcoma
(a) Most common age group
(b) Most common location
(c) Can be secondary to what other disease
Osteosarcoma = malignant bone-forming tumor
(a) Mostly in teens
(b) > 50% around the knee, predilection from metaphysis of long bones
(c) Can be secondary to Paget’s disease
Osteosarcoma
(a) Gross appearance
(b) Significance of Codman’s triangle
Osteosarcoma
(a) Grossly: large destructive lesion destroying the cortex and extending in soft tissue
(b) Codman’s triangle = radiographic finding of the periosteal surface being lifted up as the bone permeates underneath, showing that the tumor has broken thru the cortex and periosteal membrane
Best predictor of prognosis for
(a) Osteosarcoma
(b) Chondrosarcoma
Predictor of prognosis
(a) Osteosarcoma- best prognostic indicator is response to chemo
- post-chemo tumor necrosis of > 90% has the best prognosis
(b) Chondrosarcoma- best prognostic indicator is grade
- grade = histologically how similar the cells look like normal cartilage
Histological findings of osteosarcoma
Pink lace-like osteoid (no inorganic matrix)
- production of both malignant bone and malignant (abnormal) cartilage tissue
- cells are large, dark, pleomorphic w/ high mitotic activity
Which two bone cancers are exostosis
Exostosis meaning they come out of the bone
= osteochondromas (stalk w/ cartilage cap)
= osteoma (just a little bump of bone)
Describe the morphology of an osteochondroma
(a) Differentiate osteochondromas from osteoma
“cauliflower” like lesion w/ a bony stalk growing out of the metaphysis and cartilaginous cap
(a) Osteochondromas have both bony stalk and cartilaginous cap, while osteoma just have a litte bony protuberance
What is special about osteochondroma in a skull bone
UM TRICKED YA DAT SHITS IMPOSSIBLE
Osteochondromas ONLY occur on bones that form by endochondral ossification (so long bones)
Distinguish the difference in metastatic potential btwn osteochondromas and osteomas
Osteochondromas have a small malignant potential- rare but possible malignant transformation into chondrosarcomas
While osteomas DO NOT malignantly transform into osteosarcomas
When do osteochondromas stop growing?
It’s like an irregular growth plate so the osteochondroma stops growing when skeletal maturity is reached
What is a chondroma?
Benign tumor of hyaline cartilage
-so different from osteochondroma b/c there’s no ‘osteo’ => no bony component
Chondroma
(a) Radiologic appearance
(b) Gross appearance
Chondroma
(a) Radiolgoically: popcorn shaped lucent lesions in appendicular skeleton
(b) Grossly- slate blue (cartilage is slate blue/whiteish color) circumscribed lobulated nodules that do not infiltrate soft tissue
Which tumor is associated w/ Maffucci’s syndrome
Rare syndrome (w/e) but associated w/ large chondromas
-so chondromas are not clinically relevate unless associated w/ bone deformities + hemangiomas = Maffucci’s
What are chondrosarcomas?
(a) Radiologic appearance
(b) Age group
(c) Common areas
Chondrosarcoma = malignant neoplasm producing cartilaginous matrix
(a) Radiologically: “soap bubble” appearance, think circulatr like the isogenous groups that cartilage grows in
(b) Always > 40
- many bone tumors cna present w/ clinically enlarging mass, but isn’t a chondrosarcoma if pt is
How are most chondrosarcomas treated?
Most (luckily) chondrosarcomas are low grade and indolent => treatable by large resection