AIMS: Three cases of endometrioid adenocarcinoma arising in colorectal endometriosis are described with discussion of their macroscopic and microscopic pathology and diagnosis, using immunohistochemistry. METHODS AND RESULTS: Three middle-aged women presented with symptoms and signs of colorectal mass effect. Two had a preceding history of gynaecological endometriosis and all three had either been on hormone replacement therapy or had functioning ovaries prior to presentation with colorectal disease. Each underwent resection of tumours of the distal large intestine. The definitive diagnosis was dependent on histological examination and immunohistochemistry, which was used to demonstrate an origin in endometriotic tissue. CONCLUSIONS: Endometrioid adenocarcinoma is a rare complication of colorectal endometriosis, this report contributing to a total of 25 cases in the literature. Definitive diagnosis, aided by immunohistochemical studies, is important to enable the identification of the optimal management for this uncommon condition.
AIMS: Three cases of endometrioid adenocarcinoma arising in colorectal endometriosis are described with discussion of their macroscopic and microscopic pathology and diagnosis, using immunohistochemistry. METHODS AND RESULTS: Three middle-aged women presented with symptoms and signs of colorectal mass effect. Two had a preceding history of gynaecological endometriosis and all three had either been on hormone replacement therapy or had functioning ovaries prior to presentation with colorectal disease. Each underwent resection of tumours of the distal large intestine. The definitive diagnosis was dependent on histological examination and immunohistochemistry, which was used to demonstrate an origin in endometriotic tissue. CONCLUSIONS:Endometrioid adenocarcinoma is a rare complication of colorectal endometriosis, this report contributing to a total of 25 cases in the literature. Definitive diagnosis, aided by immunohistochemical studies, is important to enable the identification of the optimal management for this uncommon condition.