Histology of an incidental 3 cm solid ovarian nodule removed at laparotomy shows well-circumscribed nests of transitional-type epithelium embedded in densely fibrous stroma. Many nuclei show distinct longitudinal grooves. No atypia or mitoses are seen. What is the diagnosis?

• A Fibroma
• B Benign Brenner tumour ✓
• C Adult granulosa cell tumour
• D Serous adenofibroma

Explanation

Nests of urothelial-like transitional epithelium in fibrous stroma with grooved coffee bean nuclei define the Brenner tumour, thought to arise from Walthard cell rests. It is usually small, solid, incidental, and frequently coexists with a mucinous cystic tumour. Fibroma lacks epithelial nests, granulosa cell tumour shows Call-Exner bodies and nuclear grooves diffusely rather than in urothelial nests, and adenofibroma has tubular glands lined by serous epithelium.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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