Retroperitoneal 'uterus-like mass' of cervical origin.

We report a rare case of a retroperitoneal uterus-like mass communicating with the endocervix, which presented as abdominal pain and bloating associated with severe irregular vaginal and postcoital bleeding. Our patient did not have any structural abnormalities of the urogenital system or otherwise, which makes a müllerian defect unlikely in our case. Based on the diagnostic criteria for the choristoma, that theory would be excluded here as the mass communicated with the endocervix. This strengthens the theory of metaplasia, under the effect of oestrogen and accelerated by the hyperoestrogenic state of pregnancy as the most likely postulate for our patient. Although the uterus-like mass is not commonly reported, it should be considered as a possible differential for pelvic masses.