Soft tissue
Adipose tissue
Myolipoma

Author: Vijay Shankar, M.D.

Revised: 28 March 2018, last major update August 2012

Copyright: (c) 2002-2018, PathologyOutlines.com, Inc.

PubMed Search: Myolipoma

Cite this page: Shankar, V. Myolipoma. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/softtissueadiposemyolipoma.html. Accessed July 22nd, 2018.
Definition / general
Terminology
  • Called lipoleiomyoma in uterus
  • Note: myelolipoma is tumor with hematopoietic (including myeloid) elements, often in adrenal gland
Epidemiology
  • Very rare tumor of adults in abdomen, retroperitoneum or abdominal wall
  • Other rare sites include eyelid, pericardium, base of tongue
Radiology images

Images hosted on PathOut server
Contributed by Drs. Arno Vanstapel and Raf Sciot, Case of the Week #452:

CT abdomen frontal

CT abdomen transverse

Case reports
Treatment
  • Excision
  • Does not recur, metastasize or transform
Gross description
  • Often 9 cm or more, completely or partially encapsulated, yellow-white
Gross images

Images hosted on PathOut server
Contributed by Drs. Arno Vanstapel and Raf Sciot, Case of the Week #452:




Images hosted on other servers:

Fatty tissue with bands and nodules of firm white tissue

Microscopic (histologic) description
  • Mature adipose tissue and mature (well differentiated) smooth muscle in short fascicles (Stanford University)
  • Variable fibrosis and inflammation
  • No floret cells, no thick walled vessels, no necrosis, no mitotic figures
Microscopic (histologic) images

Images hosted on PathOut server
Contributed by Drs. Arno Vanstapel and Raf Sciot, Case of the Week #452:

5x

10x

20x








Images hosted on other servers:

Mature fat and smooth muscle fibers

Low magnification view of myolipoma

Smooth muscle fibers are SMA+ (left), desmin+ (right)

Positive stains
Differential diagnosis
Board review question #1
Which of the following immunohistochemical stains would help distinguish retroperitoneal myolipoma from a well differentiated liposarcoma invading smooth muscle?

A. CDK4
B. HMB45
C. S100
D. Smooth muscle actin
E. Vimentin
Board review answer #1
A. CDK4