Urachal adenocarcinoma: a clinician's guide for treatment.

Urachal carcinoma is a rare non-urothelial malignancy frequently involving the midline or dome of the bladder due to direct extension from the urachal ligament, the structure from which this tumor arises. Nearly always an adenocarcinoma, it is important to recognize the diagnosis upfront due to the differences in surgery and chemotherapy as compared to traditional urothelial cancer. For patients with surgically resectable tumors, a partial cystectomy with en-bloc resection of the urachal ligament with the bladder dome and umbilicus is required to appropriately control the tumor. Leaving the umbilicus in place provides inadequate control and has been associated with a higher risk of relapse. A lymph node dissection also may help in the control of this cancer. While there is yet no proven role for neoadjuvant or adjuvant chemotherapy, combinations of 5-fluoruracil with cisplatin are active in those with metastases. Since the activity of this combination also has lead to surgical consolidation of node-positive disease, one might consider the potential for benefit from perioperative chemotherapy. A higher risk of relapse following surgery has been reported in those with positive margins, lymph node involvement, involvement of the peritoneal surface, or where the umbilicus was not resected en-bloc, and may predict a group of patients where the risk of relapse is sufficiently high enough to consider adjuvant chemotherapy. A recent clinical trial of 5-fluorouracil, leucovorin, gemcitabine, and cisplatin has recently completed accrual in metastatic urachal carcinoma, with patients now in long-term follow-up.