A 48-year-old woman undergoing hysterectomy for fibroids is found to have a 3 cm firm, yellow-white solid ovarian nodule. Histology shows well-demarcated nests of epithelial cells resembling urothelium set in dense fibrous stroma, with nuclei showing prominent longitudinal grooves. Some nests contain central cystic spaces filled with mucin. What is the diagnosis?

• A Serous cystadenoma
• B Metastatic transitional cell carcinoma of the bladder
• C Fibrothecoma
• D Brenner tumour ✓

Explanation

The nests of transitional-type epithelium with coffee-bean nuclei bearing longitudinal grooves are diagnostic of a Brenner tumour. These are benign surface epithelial-stromal tumours, usually small, solid and incidental, and they commonly show focal mucinous metaplasia within the nests. Serous cystadenoma is a cystic tumour lined by ciliated columnar epithelium and lacks transitional nests, which eliminates option A. Fibrothecoma lacks epithelial nests entirely.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.