# A Rare Presentation of Polypoid Endometriosis of the Douglas Pouch: Case Report

## TL;DR

A 46-year-old woman with abnormal bleeding had a rare case of polypoid endometriosis in the Douglas pouch, initially mistaken for a tumor on MRI.

## Contribution

Highlights the rare presentation of polypoid endometriosis and its potential misdiagnosis as a malignancy.

## Key findings

- MRI showed a mass near the uterus, initially suspected to be an ovarian tumor.
- Histology confirmed the lesion was polypoid endometriosis from the Douglas pouch.
- The case emphasizes the importance of MRI features in distinguishing benign from malignant lesions.

## Abstract

A case is reported of a 46-year-old woman referred to a magnetic resonance imaging (MRI) for menometrorrhagia. MRI revealed a mass lesion lateral to the uterus fundus, suspicious of an ovarian granulosa cell tumor. Extensive surgery was performed. Histological examination revealed a polypoid endometriosis lesion arising from the Douglas pouch.

Teaching point: Polypoid endometriosis is a rare benign entity with a challenging differential diagnosis from malignancy. Specific MRI features can contribute to the diagnosis and thus avoid excessive surgical resection.