Smooth muscle, cartilage, fat, connective tissue tumors

Question 1

Where do piloleiomyomas arise from?

Answer 1

Errector pili muscle

Question 2

Staining for myocytes?

Answer 2

Desmin +, SMA +

Question 3

M/c presentation of angioleimyomas?

Answer 3

Lower extremity of middle-aged females

Question 4

3 variants of leiomyosarcomas?

Answer 4

Superficial, dermal and subQ

Question 5

Conditions a/w multiple lipomas?

Answer 5

Gardner, Bannayan-Riley-Ruvalcaba syndrome, proteus, CLOVES, PTEN hamartoma

Question 6

Epi of angiolipoma?

Answer 6

M/c seen in young adults on the forearm

Question 7

3 types of leiomyomas?

Answer 7

piloleiomyoma, genital leiomyoma, and angioleiomyoma

Question 8

Name 5 benign adipose tissue-based tumors

Answer 8

Lipoma, angiolimpoma, spindle cell/pleomorphic lipoma, hibernoma

Question 9

Malignant adipose tissue-based tumors?

Answer 9

Liposarcoma

Question 10

Benign cartilage tissue-based tumor?

Answer 10

Extraskeletal chondroma

Question 11

Malignant tissue-based tumor?

Answer 11

Chondrosarcoma

Question 12

What are 2 benign smooth muscle-based tumors?

Answer 12

Leiomyomas and smooth muscle hamartoma

Question 13

What are the painful cutaneous nodular/dermal tumors?

Answer 13

BLEND AN EGG B - blue rubber bleb L - Leiomyoma E - eccrine spiradenoma N - Neuroma D - dermatofibroma A - angiolimpoma N - neurilemmoma (schwannoma) E - Endometrioma G - glomus tumor G - Granular cell tumor

Question 14

What syndrome might you be concerned about if you saw multiple piloleiomyomas? What is the mutation and what other things do you see?

Answer 14

Reed syndrome, fumarate hydratase mutation. Also see renal cell cancer and uterine leiomyomas.

Question 15

What is the clinical presentation of angioleiomyoma?

Answer 15

M/c present on the lower extremity of middle-aged females that is painful

Histology shows a proliferation of smooth muscle around the endothelial cells of vessels –> compressed lumen *desmin and SMA (+)

Question 16

What structures do dermal leiomyosarcomas arise from?

Answer 16

Arrector pili or genital smooth muscle

Question 17

What structures do subcutaneous leiomyosarcomas arise from?

Answer 17

Vascular smooth muscle

Question 18

What is the most common location for angiolipoma?

Answer 18

Young adults on the forearms, painful becuse proliferative capillaries become thrombosed

Question 19

Most common location for spindle cell/pleomorphic lipoma

Answer 19

Back of the neck in adult men

Question 20

What stain is positive in the spindle cells in a spindle cell/pleomorphic lipoma?

Answer 20

CD34+

Question 21

What is the clinical and histologic presentation of a hibernoma?

Answer 21

M/c locations include the interscapular area, thighs, neck, and chest. Clinical is indistinct from a lipoma, the difference is its made up of immature/embryonic fat or brown fat

Histology is distinct: hibernoma cells are more polygonal with eosinophilic multivacuolated cytoplasm mixed with normal-appearing adipocytes

Question 22

What is the histology of a liposarcoma/atypical lipomatous tumor?

Answer 22

Liposarcoma/atypical lipomatous tumor:

Deep SubQ tumor, you have to identify lipoblasts which are immature fat cells with hyperchromatic nucleus that has scalloped cytoplasmic vacuoles.

MDM2 and CDK4 amplification can aid in diagnosis (99% sensitivity)

Question 23

What is the histology of a myxoid/round cell liposarcoma?

Answer 23

The key to these is the histology “chicken-wire” vessels. Otherwise similar atypical lipoblasts