Case 108

A 77-year-old female with a 5.4 cm ovary mass. The patient has a history of endometriosis.

1. What's the favored diagnosis?

   A: Endometrioid adenocarcinoma

   B: High grade serous carcinoma

   C: Malignant Brenner tumor

   D: Granulosa cell tumor

Answer

This is a case of endometroid adenocarcinoma. This trabecular pattern is also reported.

DNA MMR Proteins: Intact/normal expression of PMS2, MLH1, MSH6 and MSH2.

p53: Normal (wild type)

FOLR1: Negative by PS2 criteria

HER2 (IHC): Negative (no staining)

Estrogen receptor: Positive (70%, 2+)

Progesterone receptor: Positive (95%, 3+)

Case credit: UCSD Pathology

Author: Wangpan Jackson Shi, MD