E2L20 Soft Tissue Tumors Tullot

Question 1

What are the tumors of adipose tissue?

Answer 1

Lipoma

Liposarcoma

Question 2

What are the myofibroblastic tumors?

Answer 2

Nodular Fasciitis
Myositis Ossificans
Superficial Fibromatoses
Deep Fibromatoses (Desmoid)

Question 3

What are the fibrohistiocytic tumors?

Answer 3

Dermatofibroma

DFSP

Question 4

What are the tumors of uncertain origin?

Answer 4

Synovial Sarcoma

Undifferentiated Pleomorphic Sarcoma

Question 5

Patient has the most common benign soft tissue tumor of adulthood. Diagnosis, cell type, clinical presentation, variants.

Answer 5

Lipoma of mature fat cells
Clinical: soft, subQ, mobile, painless, slow growing
Variant: Angiolipoma= multiple, painful, on extremities

Question 6

Tumor found in deep soft tissue of proximal extremities and retroperitoneum, Histo shows lipoblasts. Diagnosis?

Answer 6

Liposarcoma
Most common soft tissue sarcoma
Malignant tumor of fat cells

Question 7

Patient young adult with fast growing tumor on flexor surface of forearm. Likely diagnosis? Px? Other features?

Answer 7

Nodular fasciitis
myofibroblastic proliferation
Self-Limited, tumor-like but benign
Resembles sarcoma and often called pseudosarcomatous fasciitis
Grows fast, poorly defined, nodular, usually

Question 8

Name the superficial fibromatoses

Answer 8

Palmar fibromatosis: dupuytren flexion contracture
Plantar fibromatosis: tends to recur after excision, contracture of toes uncommon
Peyronie’s disease: penile

All will be smooth muscle actin positive

Question 9

Postpartum woman presents with aggressive locally growing tumor assoc. c rectus abdominis muscle. Diagnosis? Other features? Mutations? Risk factors? Histo?

Answer 9

Deep fibromatosis (Desmoids)
Deep masses appearing in young adults and especially postpartum women in the abs and in scars from abd surgery
Aggressive local growth, tend to recur, benign
Mutations in APC gene or Beta-catenin
Assoc. c FAP, Gardner syndrome
Histo: myofibroblast (smooth muscle actin +)

Question 10

Patient has a fast growing mass that is found to be + APC gene mutation and an accumulation of beta-catenin. Diagnosis?

Answer 10

Deep Fibromatosis (Desmoids)

Question 11

Tumor found to be SMA positive. What does this mean?

Answer 11

Smooth Muscle Actin positive

Means it resembles smooth muscle and is likely a Myofibroblastic tumor

Question 12

What tumor has a herringbone pattern on histo?

Answer 12

Fibrosarcoma

Question 13

Small brown/tan papule found on leg of a woman that is non-tender and appeared after local trauma. Diagnosis? Test? Histo?

Answer 13

Dermatofibroma
Benign FIbrous Histiocytoma
Common on LE of females after traums
Dimple or Collar Button Sign
Histo: positive for factor XIIIA normally found in dendritic cells

Question 14

Tumor found on trunk/back and shows storiform pattern on histo. Diagnosis? Group? Other features?

Answer 14

Dermatofibrosarcoma Protruberans
Primary tumor of the skin of fibrohistiocytic origin
Slow growing, rarely metastasizes
Recurs after incomplete excision
Trunk location
Involved with collagen gene translocation with PDGF gene

Question 15

Describe features of Embryonal rhabdomyosarcoma

Answer 15

Most common rhabdomyosarcoma
Children most commonly
Includes Sarcoma Botryoides which is grape-like clustering
Most often found in the vagina of young girls

Question 16

Describe features of Undifferentiated Pleomorphic Sarcoma

Answer 16

Broad category for all high grade sarcomas that don’t fit other categories
Proximal extremities and retroperitoneum
Aggressively malignant and often metastasize
Morphology: spindle cells, storiform/cartwheel pattern, xanthoma cells and bizarre giant cells

Question 17

Sarcoma found to have a biphasic growth pattern of epithelial gland-like cells and fibroblast-like spindle cells. Diagnosis and other features?

Answer 17

Synovial Sarcoma
Highly malignant soft tissue tumor most common in 20-40y
Unknown cell origin
Commonly in knee or thigh but can be in viscera, head, neck
t(X:18) balanced translocation; fusion gene protein transcription factors

Question 18

How do sarcoma like to spread?

Answer 18

Hematogenously

Therefore lymph dissection not often needed