Case 7

A 30-year-old female with an ovarian mass.

1. What is the diagnosis by morphology?

   A: Fibroma

   B: Thecoma

   C: Signet ring stromal tumor

   D: Adult granulosa cell tumor

   E: Sclerosing stromal tumor

Answer

The correct answer is E. This is a classic case of sclerosing stromal tumor: 1) alternating cellularity 2) pseudo-lobular appearance 3) thin walled dilated staghorn vessels. The pseudolobules in a myxoid, edematous, or collagenous stroma is characteristic.

2. What is the molecular change in this pure stromal tumor?

   A: CTNNB1 mutation

   B: FOXL2 mutation

   C: DICER1 mutation

   D: GLI2 rearrangment

   F: PTEN mutation

Answer

The correct answer is D. Recurrent FHL2-GLI2 fusion and trisomy 12 are identified in sclerosing stromal tumor. CTNNB1 mutation is seen in microcystic stromal tumor. DICER1 mutation is seen in moderately to poorly differentiated sertoli-leydig cell tumor and a subset of cervical rhabdomyosarcoma. PTEN mutation is seen in Cowden syndrome and is aossciated with endometroid endometrial carcinoma.

Reference: https://www.pathologyoutlines.com/topic/ovarytumorsclerosingstroma.html

https://tumourclassification.iarc.who.int/chaptercontent/34/71

Case credit: UCSD Pathology

Author: Wangpan Jackson Shi, MD