Urachal adenocarcinoma metastatic to the ovary simulating primary mucinous cystadenocarcinoma of the ovary: report of a case.

A 56-year-old woman had a large multicystic ovarian tumour 4 years after undergoing partial cystectomy for a deeply invasive urachal adenocarcinoma. On microscopic examination the ovarian tumour was a moderately differentiated mucinous cystadenocarcinoma similar to the urachal tumour. Several peritoneal biopsies and the omentum were positive for metastatic adenocarcinoma. Although initially interpreted as representing primary mucinous adenocarcinoma of the ovary with peritoneal spread, subsequent comparison with the previous urachal adenocarcinoma led to re-interpretation of the ovarian tumour as metastatic urachal carcinoma. Metastatic mucinous adenocarcinomas involving the ovary may be misinterpreted as primary ovarian carcinomas and the urinary bladder is a potential source of these neoplasms.