Chapter 146 - Malignant Soft Tissue Lesions

Question 1

pre-op radiation

Answer 1

lower dose
twice the wound complications
forms a fibrotic shell around the tumor
decreases surrounding tumor edema

*surgery should be delayed 3-4 weeks following completion of radiation

Question 2

chemotherapy for soft tissue sarcoma

Answer 2

only indicated in soft-tissue predominant ewings and rhabdomyosarcoma

Question 3

what is the most important factor in determining overall prognosis/outcome in soft tissue sarcoma?

Answer 3

tumor stage

Question 4

lymph node mets in what??

Answer 4

SCARE

synovial sarcoma
clear cell sarcoma
angiosarcoma
rhabdomyosarcoma
epitheloid sarcoma

Question 5

undifferentiated pleomorphic soft tissue sarcoma

Answer 5

age 55-80
male 2:1

deep slow growing painless mass

low on T1
bright on T1

tx = surgery + radiation

Question 6

Liposarcoma

Answer 6

age 50-80
males>females

well differentiated variant = ALT in the extremitites, ring chromosome 12, MDM2 expression

myxoid liposarcoma t(12;16)
can met to spine, and abdomen
Need CT C/A/P and MRI/CT spine for staging

Question 7

histo of myxoid liposarcoma

Answer 7

Question 8

histo of dedifferentiated liposarcoma

Answer 8

Question 9

histo of pleomorphic liposarcoma

Answer 9

Question 10

fibrosarcoma

Answer 10

males>females 30-55
slow growing painless mass around the knee/thigh
can get ulceration of the skin in superficial lesions

histo: fasiculated herringbone pattern with bland fibroblasts

tx: wide resection and radiation

Question 11

dermatofibrosarcoma protuberans

Answer 11

t(17;22)

dermal skin layers

wide margins, imatinib (tyrosine kinase inhibitors)

Question 12

synovial sarcoma

Answer 12

juxta-articular - these are NOT intra-articular lesions

young people -15-40
male>females

t(X;18) - SYT-SSX

calcifications on plain XR
Low T1, high T2 (like all soft tissue sarcomas)

path: biphasic - gland-like epithelia plus elongated spindle cells

lymph node mets in 10-12%
heavily calcified lesions = better prognosis

Question 13

epitheloid sarcoma

Answer 13

age 10-35
males 2:1

expresses Ca-125

frequently involves the hands, forearm, fingers - most common soft tissue sarcoma of the hand/wrist

nodular pattern with central necrosis

Question 14

clear cell sarcoma

Answer 14

20-40yo, females>males
malignant melanoma of soft parts

t(12;22)

foot, ankle, knee, hand

frequently mets to nodes
frequently mets to lungs with a terrible prognosis
no effective chemo

tx : wide excision and radiation

Question 15

rhabdomyosarcoma

Answer 15

occurs in children 0-20

embryonal occurs age 0-4 males>females

alveolar more in adolescents <20 male=female
t(2;13) Pax-Fkr

head/neck, retroperitoneal, or GU

staging needs to include a bone marrow biopsy

path: stains for desmin, myoglobin, and MyoD1

treatment: multimodal chemo!!!! (besides soft tissue ewings this is the ONLY soft tissue sarcoma that is treated with chemo)
vincristine, cyclophosphamide
ifosfamide

regional node mets common