Urachal Adenocarcinoma with a Concomitant Urachal Remnant: A Case Report

ABSTRACT

Urachal adenocarcinoma is a rare tumor, and it has similarities with nonurachal adenocarcinoma; therefore, it is sometimes difficult to make a diagnosis. We present a typical case of urachal adenocarcinoma that had all the diagnostic criteria including the presence of an urachal remnant. A 65-year-old woman presented with complaints of a painless gross hematuria. Pelvic CT and cystoscopy showed an intraluminal protruding mass centered in the bladder wall. When diagnosed as adenocarcinoma with a signet ring cell component being noted by frozen biopsy, partial cystectomy with resection of the median umbilical ligament and peritoneum was carried out for a suspected urachal adenocarcinoma. The tumor morphology showed as typical mucinous adenocarcinoma. Characteristic tubular structures showing the typical histology of an urachal remnant was found in the perivesical fat. On immunohistochemical staining, the urachal adenocarcinoma showed a pattern similar to colonic adenocarcinoma, while the urachal remnant showed strong positivity for CK7 and Chromogranin A.