The occurrence of urachal carcinoma during ten years of following of urothelial carcinoma

Background : Urachal carcinoma is an extremely rare tumor. We describe a case of urachal carcinoma occurring 10 years after surgical resection of urothelial carcinoma of the urinary bladder. Case : A 70-year-old man was admitted with hematuria. He had been diagnosed as having and been treated for urothelial carcinoma 10 years ago. CT revealed an irregular pelvic tumor at the adventitial site of the dome of the bladder. Urine cytology revealed large clusters of round to columnar cells with hyperchromatic and irregular nuclei, occasional prominent nucleoli, and intracytoplasmic lumina (ICL). These findings differed from those of the previously reported urothelial carcinomas, and based on these new cytological findings, urachal carcinoma was suspected. Conclusion : Urachal carcinoma is very rarely encountered in cytological specimens practice, but should be considered in the event of detection of overlapping large clusters of cells, including columnar cells, with ICL.