[A case of urachal carcinoma treated with S-1/CDDP combination chemotherapy].

No established treatment exists for urachal carcinoma,except curative resection,and its prognosis is poor. More than 80% of urachal carcinomas are adenocarcinomas. We report a case of advanced urachal carcinoma treated with S-1 and cisplatin combination (S-1/CDDP) chemotherapy. The patient,a 61-year-old woman,presented with macroscopic hematuria. A tumor was detected on the bladder dome and transurethral resection was performed. Histopathological findings indicated poorly differentiated adenocarcinoma. Serum carcinoembryonic antigen and carbohydrate antigen 19-9 levels were 3.5 ng/ml and 140 U/ml respectively. Magnetic resonance images indicated an extension of this tumor to the retroperioneal space. Metastasis to her right ischium was suspected from bone scintigraphy results. The tumor was diagnosed as stage IVB (Sheldon's category) urachal carcinoma. After one cycle of S-1/CDDP chemotherapy,the size of the tumor on the bladder dome decreased,after which total cystectomy was performed. The surgical margin of the cystectomy specimen was negative for malignant cells,although poorly differentiated adenocarcinoma was still observed in this specimen. The findings of this study indicate that this therapy might be beneficial for treating advanced urachal carcinomas. This is the second report of successful treatment of advanced urachal carcinoma with S-1/CDDP chemotherapy.