Oncology

Question 1

Smooth muscle actin (SMa)

Answer 1

smooth muscle –> leiomyosarcoma

Question 2

Desmin

Answer 2

skeletal muscle –> rhabdomyosarcoma

Question 3

S-100

Answer 3

neural –> schwannoma, MPNST

Question 4

CD34/CD31

Answer 4

endothelial cell –> hemangioma, angiosarcoma

Question 5

beta catenin

Answer 5

membrane marker/WNT pathway –> fibromatosis

Question 6

CD99

Answer 6

Ewing’s

Question 7

IN1 (integrase interactor 1)

Answer 7

epithelioid sarcoma

Question 8

Keratin

Answer 8

epithelioid sarcoma, synovial sarcoma, carcinoma

Question 9

EMA (epithelial membrane antigen)

Answer 9

epithelioid sarcomas, synovial sarcomas

Question 10

Myod1/Myogenin (Myf-4)

Answer 10

skeletal muscle –> rhabdomyosarcoma

Question 11

vimentin

Answer 11

soft tissue sarcoma

Question 12

Ewing’s chromosomal abnormality and gene

Answer 12

t(11;22)

EWS-FLI1

Question 13

Myxoid liposarcoma chromosomal abnormality and gene

Answer 13

t(12;16)

TLS-CHOP

Question 14

Alveolar rhabdomyosarcoma chromosomal abnormality and gene

Answer 14

t(2;13)

PAX3-FKHR

Question 15

Clear cell sarcoma chromosomal abnormality and gene

Answer 15

t(12;22)

EWS-ATF1

Question 16

Synovial Sarcoma chromosomal abnormality and gene

Answer 16

t(X;18)

SSX1-SYT

Question 17

Myxoid chondrosarcoma chromosomal abnormality and gene

Answer 17

t(9;22)

EWS-CHN

Question 18

Fibrosarcoma histology

Answer 18

herringbone pattern

Question 19

Malignant peripheral nerve sheath tumor gene and histology

Answer 19

gene: NF1
histology: spindle cells in a whirling pattern, S100 positive

Question 20

Angiosarcoma histology

Answer 20

• epithelioid nests
• spindle cells
• rudiementary vascular channels (how to differentiate from other sarcomas)
• CD 34

Question 21

Loss of IN1

Answer 21

epithelioid sarcoma

Question 22

Epithelioid sarcoma histology

Answer 22

nodular growth pattern, mixed polygonal cells with eosinophilic cytoplasm mixed with spindle and epithelioid cells

Question 23

Fibromatosis on MRI

Answer 23

dark on T1 and T2

Question 24

Pathology of extra abdominal desmoid

Answer 24

spindle cells in a collagenous stroma
invades muscle
IHC beta catenin
estrogen receptor

Question 25

Schwannoma/Neurilemmoma histology

Answer 25

nuclear palisading with verocay bodies (Antoni A) and loose haphazard collagen matrix (Antoni B)

Question 26

Periosteal osteosarcoma histology

Answer 26

chondroblastic components with malignant bone formation

Question 27

Treatment of periosteal osteosarcoma

Answer 27

same as conventional (chemo and surgery)

Question 28

Histology of telangiectatic OSA

Answer 28

• malignant osteoid
• vascular lakes and channels
• giant cells

Question 29

Histology of NOF

Answer 29

spindle shaped fibroblasts, whorled pattern, giant cells, hemosiderin

Question 30

Lymphoma differentiators from other blue cell tumors

Answer 30

CD45+

LCA (leukocyte common antigen)

Question 31

Ewings differentiators from other blue cell tumors

Answer 31

vimentin positive
keratin positive
CD99 positive

Question 32

Rhabdomyosarcoma differentiators from other blue cell tumors

Answer 32

Desmin positive

Question 33

Neuroblastoma differentiators from other blue cell tumors

Answer 33

NSE (neuron specific endolase)

NB 84

Question 34

Myeloma differentiators from other blue cell tumors

Answer 34

CD56+

CD20+

Question 35

Skeletal metastases most commonly occur in…

Answer 35

the spine due to batson’s plexus.

Question 36

The most common location for localized PVNS is…

Answer 36

anterior knee.