# Brenner Tumour

> Brenner tumour for NEET-PG Obstetrics and Gynaecology: transitional cell ovarian tumour, coffee bean nuclei, benign behaviour, imaging and differentials.

- Canonical URL: https://prepelephant.com/topics/neet-pg/obstetrics-and-gynaecology/brenner-tumour
- Exam / course: NEET-PG · Subject: Obstetrics and Gynaecology
- Publisher: PrepElephant (https://prepelephant.com) — Prepared and reviewed by the PrepElephant Academic Review Team
- First published: 2026-10-14
- Last updated: 2026-10-14
- Reference basis: Williams Gynecology; WHO Classification of Female Genital Tumours; Dutta's Textbook of Gynecology
- How to cite: "Brenner Tumour", PrepElephant, https://prepelephant.com/topics/neet-pg/obstetrics-and-gynaecology/brenner-tumour

## Direct answer

Brenner tumour is a rare ovarian tumour made of nests of transitional cell epithelium set in a dense fibrous stroma, and most cases are benign. Its diagnostic feature is the coffee bean nucleus of the transitional cells, seen on histology. It is typically a solid, mostly unilateral mass in middle-aged and older women.

## What you must remember

- **Histology:** Nests of transitional, urothelial-type epithelium lie within a dense fibrous stroma.
- **Diagnostic feature:** The transitional cells have coffee bean nuclei with longitudinal nuclear grooves.
- **Behaviour:** Most Brenner tumours are benign, and malignant forms are rare.
- **Age and laterality:** The tumour occurs mainly in middle-aged and older women and is usually unilateral.
- **Imaging:** It is typically solid, often calcified, and low on T2-weighted MRI, which helps separate it from cystic tumours.
- **Coexistence:** Brenner tumour may coexist with mucinous change, so the mucinous component should be examined fully.
- **Presumed origin:** Transitional metaplasia from Walthard cell nests is the commonly proposed origin.
- **Treatment:** Benign disease is treated by excision, and fertility-sparing surgery is considered in young women.

## How a Brenner tumour is recognised and managed

A solid ovarian mass with imaging features of Brenner tumour is confirmed on histology before treatment is planned. The steps below move from suspicion to follow-up and mirror the usual clinical sequence.

1. **Suspect on imaging:** A solid ovarian mass with calcification and low T2 signal raises suspicion. The imaging is nonspecific, so the diagnosis is not made on it alone.
2. **Confirm histology:** Transitional nests with coffee bean nuclei within dense fibrous stroma establish the diagnosis. Immunohistochemistry is used when the histology is uncertain.
3. **Exclude malignancy:** Pathologists look for atypia, invasion and a malignant component. Malignant Brenner tumour is rare, but it is managed as an ovarian carcinoma when present.
4. **Examine the other side:** The contralateral ovary, the uterus and the mucinous component are assessed, since coexisting lesions are possible.
5. **Plan the surgery:** Unilateral excision is adequate for benign disease, and young women wanting fertility may keep the uterus and the other ovary. Frozen section helps guide the intraoperative decision.
6. **Follow up:** Patients with benign disease are reviewed for recurrence and for any new pelvic pathology, as the prognosis is excellent.

## Where the exam tries to catch you

Brenner questions test histology and the difference from look-alike solid tumours.

- **Trap:** Calling every solid ovarian mass a fibroma. — **Correct:** Brenner tumour is identified by its transitional nests with coffee bean nuclei, which fibroma lacks.
- **Trap:** Assuming a solid ovarian tumour is malignant. — **Correct:** Brenner tumours are solid yet mostly benign, so solidity alone does not indicate malignancy.
- **Trap:** Confirming Brenner tumour with CA-125. — **Correct:** Tumour markers are non-specific here, and histology is the decisive test.

## Frequently asked questions

### What is the histological feature of Brenner tumour?
Brenner tumour is diagnosed by nests of transitional epithelium set in dense fibrous stroma. The transitional cells have coffee bean nuclei with longitudinal grooves. Histology, not imaging, confirms the diagnosis of Brenner tumour.

### Is Brenner tumour of the ovary usually benign?
Most Brenner tumours are benign, and malignant forms are rare. Benign Brenner tumour is usually treated by excision and carries an excellent prognosis. A malignant Brenner tumour is staged and treated as an ovarian carcinoma.

### Which ovarian tumours mimic Brenner tumour on imaging?
Solid ovarian tumours such as fibroma, thecoma and solid endometrioid tumours can look similar on ultrasound and MRI. Brenner tumour is typically low on T2-weighted MRI and may calcify. Histology separates these lesions definitively.

### What surgery suits Brenner tumour in a young woman?
Unilateral oophorectomy (or salpingo-oophorectomy) is usually appropriate for a benign Brenner tumour in a young woman who wants to preserve fertility. Frozen section can confirm the nature of the lesion during surgery. Staging surgery follows only if malignancy is confirmed.

### Can Brenner tumour coexist with other ovarian tumours?
Brenner tumour may coexist with mucinous tumours or mucinous change, so the mucinous component should be sampled fully. The contralateral ovary is also examined at surgery. Careful histological sampling of the whole specimen avoids missing a coexisting lesion.