Bone Tumors

Question 1

clinical presentation of bone tumors

Answer 1

pain, mass, pathological fracture, asymptomatic

Question 2

diagnostic factors

Answer 2

age, sex, skeletal location (bone, area of bone), radiographic appearance

Question 3

sclerotic margin indicates?

Answer 3

benign, slowly-growing neoplasm

Question 4

ill-defined margin indicates?

Answer 4

malignant, rapidly growing neoplasm

Question 5

solid, ivory-like pattern indicates?

Answer 5

malignant bone matrix-forming tumors

Question 6

rings and arcs (moth-eaten holes) indicate?

Answer 6

chondroid matrix-forming tumors

Question 7

most common major primary tumors involving bones

Answer 7

hematopoietic (40%), myeloma + malignant lymphoma

Question 8

most common primary bone malignancy?

Answer 8

osteosarcoma

Question 9

benign bone-forming tumors

Answer 9

osteoid osteoma & osteoblastoma (histologically similar)

Question 10

osteoid osteoma characteristics

Answer 10

long bones, femur & tibia, < 2 cm, night pain that responds to aspirin. radiolucent lesion within sclerotic cortex

Question 11

osteoblastoma characteristics

Answer 11

vertebrae or long bone metaphysis, > 2 cm, painful, not responsive to aspirin, expansile radio-lucency with mottling

Question 12

malignant mesenchymal tumor in which cells produce bony matrix or bone

Answer 12

osteosarcoma

Question 13

osteosarcoma

Answer 13

most common sarcoma of bone (35%), bimodal age distribution (M > F) mean age 15, 2nd peak 55-80. infiltrative tumor extending into soft tissue. malignant cells producing osteoid.

Question 14

osteosarcoma location + mets?

Answer 14

metaphysis of long bones, may be polyostotic. hematogeneous spread to lungs common

Question 15

osteosarcoma pathogenesis

Answer 15

inherited mutant allele of RB gene, mutation of p53 suppressor gene (Li-Fraumeni), overexpression of MDM2, INK4 and p16; sites of bone growth/dz (Paget), prior irradiation

Question 16

osteosarcoma radiography

Answer 16

poorly delineated, bone destruction, cortical disruption, bone matrix, soft tissue extension, codman’s triangle

Question 17

osteosarcoma treatment

Answer 17

1. neo-adjuvant chemo

2. surgical resection

Question 18

osteosarcoma prognosis

Answer 18

post chemo: 60-65% 3-5 year survival if non-mets. (before chemo 5 year survival 20%) >90% necrosis after chemo means near 90% survival.

Question 19

cartilaginous tumors

Answer 19

osteochondroma, enchondroma, multiple chondromatosis

Question 20

osteochondroma

Answer 20

most common benign bone tumor. metaphysis of long bones. autosomal dominant mutations in EXT-1 hereditary multiple exostoses (40% risk for malignant transformation).

Question 21

enchondroma

Answer 21

benign hyaline cartilage lesion. intramedullary chondroma. usually asymptomatic, on appendicular skeleton (eg finger)

Question 22

periosteal chondroma

Answer 22

juxtacortical chondroma (on cortical surface under periosteum)

Question 23

enchondroma on x-ray, micro?

Answer 23

x-rays: lytic, lobulated, cortical thinning.

micro: lobules of hyaline cartilage, minimal atypia

Question 24

enchondroma treatment

Answer 24

non, unless lesion shows changes (symptomatic, or evidence of recent growth after skeletal maturity)

Question 25

multiple chondromatosis

Answer 25

frequent point mutations in IDH1 or IDH2

Question 26

ollier’s disease

Answer 26

multiple enchondromata, regional distribution, w or w/o severe skeletal malformation

Question 27

maffucci’s syndrome

Answer 27

multiple enchondromata + ANGIOMATA. severe skeletal malformation. higher incidence of malignant transformation into chondrosarcoma

Question 28

chondrosarcoma

Answer 28

malignant, neoplastic cells produce cartilaginous matrix. second most common bone sarcoma (26%). older adults, above 40-50. peak during 6th and 7th decades. in central skeleton.

Question 29

chondrosarcoma imaging

Answer 29

medullary loction. present calcifications (lost in grade 3 tumors). cortical erosion or destruction. occasional soft tissue extension. popcorn like on xray

Question 30

chondrosarcoma pathology

Answer 30

more cellular, nuclei more pleomorphic than in enchondromas. binucleation frequent. myxoid change. size and grade correlate w behavior.

Question 31

chondrosarcoma survival

Answer 31

grades 1, 2 5 year survival: 80-90%, grade 3 5 yr 29% (pulmonary mets)

Question 32

chondrosarcoma variants

Answer 32

de-differentiated

Question 33

de-differentiated chondrosarcoma

Answer 33

cells look generic, no cartilage formation

Question 34

fibrous bone tumors

Answer 34

non-ossifying fibroma, fibrous dysplasia

Question 35

non-ossifying fibroma

Answer 35

common devo cortical defect, 25% multifocal. tibia, femur (metaphysis) in 1-3rd decades. eccentric, lytic, peripheral sclerosis. incidental finding or pathologic fracture. starry night histo.

Question 36

fibrous dysplasia

Answer 36

devo arrest of bone. monostotic is most common- adolescents: ribs, jaw, femur. polyostotic- infancy/childhood: crippling deformities, craniofacial involvement

Question 37

McCune-Albright syndrome

Answer 37

polyostotic FD with endocrinopathies, cafe-au-lait spots. rare, F > M. sexual precocity, acromegaly, cushing. activating germline mutations of GNAS lead to excess cAMP leads to endocrine gland hyperfunction

Question 38

fibrous dysplasia on radiograph

Answer 38

expansile, circumscribed, thinned cortex, ground glass appearance, may be multiple

Question 39

fibrous dysplasia pathology

Answer 39

haphazard, curvilinear chinese characters surrounded by fibroblastic stroma. no significant osteoblastic rimming.

Question 40

ewing sarcoma /PNET

Answer 40

2nd most common malignant bone tumor in kids. M > F. adolescents, young adults. painful, often enlarging mass on diaphysis of long tubular bones, ribs and pelvis

Question 41

ewing sarcoma /PNET x-ray

Answer 41

moth eaten, permeative medullary lesion with large soft tissue mass. onion skin pattern.

Question 42

ewing sarcoma /PNET pathology

Answer 42

sheets of primitive small round blue cells, neural phenotype. CD99. abundant glycogen. hemorrhage and necrosis common. mitotic activity

Question 43

ewing sarcoma /PNET pathogenesis

Answer 43

EWS involved in > 95% of ES/PNET. t(11;22) in 85% of tumors (EWS on 22q fused with FLI-1 transcription factor on 11q)

Question 44

ewing sarcoma /PNET treatment

Answer 44

chemo + surgery, radiation therapy. stage 1: 5 year survival 70% w chemo/RT

Question 45

giant cell tumor of bone

Answer 45

20-40 yo, older adolescents; F > M. epiphyseal location (knee, prox humerus, radius). most are benign, locally aggressive, may destroy cortex of bone and extend into soft tissue. infiltrative but no mets.

Question 46

metastatic bone tumors

Answer 46

most common malignant bone tumor esp in adults. mostly multiple. solitary lesions may mimic primary bone tumor; 70% to axial skeleton, mostly lytic, may be blastic. 80%: BLT-KP.