Positive Response to Fluorouracil and Oxaliplatin in Signet Ring Cell Adenocarcinoma of the Bladder Presenting With Retroperitoneal Fibrosis.

Bladder adenocarcinoma is an uncommon type of bladder cancer. Signet ring cell pathology is a rare subtype of bladder adenocarcinoma. Global incidence rates of signet ring cell adenocarcinoma of the bladder have not been established. Management of signet cell bladder cancer is challenging as it is aggressive in behavior with frequent relapse despite chemotherapy. Here we present a case of stage IV signet cell bladder cancer with retroperitoneal fibrosis treated with FOLFOX (folinic acid, 5-fluorouracil, oxaliplatin) regimen with a complete durable response.