[A Case of Bladder Adenocarcinoma with Rectal Metastasis].

A 77 year-old man with asymptomatic microscopic hematuria underwent a cystoscopic examination, which identified a broad-based papillary tumor at the cervix of the bladder. Adenocarcinoma was detected in the biopsy specimen. MRI and CT examination showed a huge papillary tumor of the bladder invading the inner lobe of the prostate. In addition, the wall of the lower rectum exhibited thickening with enlargement of the regional lymph nodes. Endoscopy disclosed a hemi-circular rectal tumor and pathological examination revealed adenocarcinoma, the profile of which was similar to the bladder tumor. The levels of CEA and CA19-9 were 5.3 ng/mL and 39 U/mL, respectively. A differential diagnosis considering bladder cancer, rectal cancer, or both was necessary before planning a treatment strategy. Since both tumors were judged to be resectable, total pelvic exenteration was carried out. Through detailed postoperative pathological examinations, it was concluded that this tumor was of bladder origin and it invaded the prostate along with metastasis to the rectum. Adenocarcinoma of the bladder is extremely rare and exhibits aggressive behavior.