Colon tumor
Mesenchymal tumors
Müllerian adenosarcoma

Author: Raul S. Gonzalez, M.D. (see Authors page)

Revised: 21 June 2017, last major update June 2017

Copyright: (c) 2003-2017,, Inc.

PubMed search: Colonic müllerian adenosarcoma

Cite this page: Müllerian adenosarcoma. website. Accessed April 21st, 2018.
Definition / general
  • Biphasic gynecologic tumor composed of benign epithelium and malignant stroma
Essential features
  • Rare in gastrointestinal tract
  • Second most common colonic lesion to arise from endometriosis, after endometrioid adenocarcinoma
Clinical features
  • Abdominal pain (may be due to the endometriosis)
  • Patients appear to have good prognosis, but few cases reported
Gross description
  • Large (up to 15 cm) solid / cystic mass involving the muscularis propria
Microscopic (histologic) description
  • Biphasic tumor containing endometrioid glands and stroma
  • Glandular component is benign but may show focal atypia
  • Stromal component shows mitotic figures, mild to moderate atypia, condensation around glands and sometimes pseudodecidualization
Microscopic (histologic) images
Images hosted on Pathout server:

Contributed by Weijie Li, MD:

Uterine adenosarcoma

Images hosted on other servers:
Missing Image

Adenosarcoma of uterus

Differential diagnosis
Board review question #1
    The most common malignancy arising in colonic endometriosis is:

  1. Colorectal adenocarcinoma
  2. Endometrioid adenocarcinoma
  3. Endometrioid adenofibroma
  4. Endometrioid stromal sarcoma
  5. Müllerian adenosarcoma
Board review answer #1
B. Endometrioid adenocarcinoma