Bone Tumors

Question 1

Gardner Syndrome

Answer 1

famililial adenomatous polyposis, fibromatosis in retroperitoneum, osteoma of facial bone

Question 2

Osteoma

Answer 2

Benign tumor of bone

Question 3

Osteoid Osteoma

Answer 3

Benign tumor of osteoblasts surrounded by a rim of reactive bone. Young adults, M > F, cortex of long bones, bone pain relieved by aspirin, bony mass with radiolucent core on imaging

Question 4

Osteoblastoma

Answer 4

Like osteoid osteoma but larger (> 2cm), arises in vertebrae, bone pain that is not relieved by aspirin

Question 5

Osteochondroma

Answer 5

Tumor of bone with an overlying cartilage cap, MC benign tumor of bone, lateral projection of growth plate, bone continuous with marrow space

Question 6

Osteosarcoma

Answer 6

Malignant prolif of osteoblasts, peak incidence in teenagers, but bimodal with incindence in elderly. Famililial retinoblastoma, paget disease, and radiation exposure are risks. Arises in metaphysis, pathologic fx, bone pain with swelling, “sunburst” and Codman triangle on imaging. Bx pleomorphic cells that produce osteoid

Question 7

Giant Cell Tumor

Answer 7

multinucleated giant cells and stromal cells, young adults, epiphysis of long bones, “soap bubble” appearance on xray, locally aggressive, may recur

Question 8

Ewing Sarcoma

Answer 8

Malignant prolif of poorly diff cells derived from neuroectoderm, diaphysis of long bones, male children on xray, 11;22 translocation, presents with metastasis, responsive to chemo. Bx small round blue cells that resemble lymphocytes.

Question 9

Chondroma

Answer 9

Benign tumor of cartilage, medulla of small bones of hands and feet

Question 10

Chondrosarcoma

Answer 10

Malignant cartilage forming tumor, medulla of pelvis or central skeleton.

Question 11

Metastasis

Answer 11

Usually lytic lesions, but can be osteoblastic (prostate cancer), more common than primary

Question 12

“Soap Bubble”

Answer 12

Giant Cell Tumor

Question 13

“onion Skin”

Answer 13

Ewing Sarcoma

Question 14

Sunburst and lifting of periosteum

Answer 14

Osteosarcoma

Question 15

Epiphyseal Tumor

Answer 15

Think Giant Cell of Bone

Question 16

Homer Wright Rosette

Answer 16

Seen in Ewing Sarcoma; dark blue tumor cells surrounding pink fibrillar material resembling neuropil

Question 17

metaphysis malignancies

Answer 17

osteosarcoma, juxtacortical osteosarcoma

Question 18

diaphysis malignancies

Answer 18

ewing sarcoma, chondrosarcoma

Question 19

epiphysis benign

Answer 19

chondroblastoma, giant cell tumor

Question 20

metaphysis benign

Answer 20

osteoblatoma, osteochondroma, non-ossifying fibroma, osteoid osteoma, chondromyxoid fibroma, giant cell tumor

Question 21

diaphysis benign

Answer 21

enchondroma, fibrous dysplasia

Question 22

sheets of uniform oval mononuc cells and numerous osteoclast type giant cells with 100+nuclei

Answer 22

giant cell tumor of bone - benign but locally aggressive. Do not produce bone or cartilage

Question 23

osteochondromas develop only in

Answer 23

bones of endochondral origin

Question 24

EXT1 or 2 loss of function mutation

Answer 24

Hereditary exostoses - germline mutations (Au Dom)

Question 25

EXT genes encode

Answer 25

enzymes that synthesize heparan sulfate glycosaminoglycans. If these are abnormal or absent, diffusion of Ihh may be prevented. Ihh is a local regulator of cartilage growth

Question 26

circumscribed lucencies with central irregular calcifications, a sclerotic rim and an intact cortex

Answer 26

chondroma

Question 27

Ollier disease

Answer 27

nonhereditary syndrome of multiple enchondromas

Question 28

Maffucci Syndrome

Answer 28

nonhered syndrome with multiple enchondromas plus multiple soft tissue hemangiomas. Increased risk of ovarian carcinomas and brain gliomas

Question 29

IDH1 and 2 mutations associated with

Answer 29

enchondromas - gene encodes isocitrate dehydrogenase

Question 30

mutated isocitrate dehydrogenase

Answer 30

produces 2-hydroxyglutarate - “oncometabolite” that interferes with regulation of DNA methylation

Question 31

well circumscribed nodules of hyaline cartilage containing cytomorphologically benign chondrocytes

Answer 31

enchondromas

Question 32

large destructive mixed blastic lytic mass with infiltrative margins

Answer 32

osteosarcoma- mc primary malign tumor of bone ~20%

Question 33

RB mutation association

Answer 33

osteosarcoma

Question 34

TP53 mut association

Answer 34

osteosarcoma

Question 35

INK4A inactivation association

Answer 35

osteosarcoma - encodes p16 and p14 tumor suppressors

Question 36

MDM2 and CDK4 overexpressed

Answer 36

osteosarcoma

Question 37

mc subtype of osteosarcoma

Answer 37

primary, intramedullary, osteoblastic, high grade occurring in metaphysis of long bones

Question 38

large, gritty gray white tumor with areas of hemorrhage and cystic degeneration

Answer 38

osteosarcoma

Question 39

formation of bone by the tumor is diagnostic

Answer 39

osteosarcoma

Question 40

foci of flocculent densities

Answer 40

chondrosarcoma on imaging

Question 41

Silencing of CDKN2A by DNA methylation association

Answer 41

chondrosarcoma

Question 42

chondrosarcoma prognosis determined by

Answer 42

tumor grade

Question 43

t(11;22) causes fusion of

Answer 43

EWS gene with FL11 gene

Question 44

metastasis to small bones of hand and feet usually from

Answer 44

lung, kidney, colon - uncommon

Question 45

produce lytic lesions upon metastasis

Answer 45

carcinomas of lung, kidney, GI tract and malignant melanoma