Introduction

Urachal cancer (UraC) is a rare malignant disease. Patients usually present with advanced mucinous adenocarcinoma, which may disseminate to the peritoneal cavity, causing peritoneal carcinomatosis (PC). Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) have been shown to improve clinical outcomes for adenocarcinomas arising from the colon and the ovary. We report our experience of structured stepwise staging and HIPEC for UraC.

Methods

Between 01/1994 and 04/2016, 56 patients with UraC were treated and followed at our institute. For this study, we excluded 8 patients (urothelial carcinoma). Structured work-up included at least a chest X-ray and an abdominal/pelvic CT-scan. Starting in 2001 diagnostic supra-umbilical laparoscopy (dLap) was introduced in patients with initial negative CT and revealed limited PC in 6/26 (23%) patients. Overall, staging (imaging and/or dLap) revealed 11 metastatic patients and another 9 patients, who had limited PC and were eligible for local excision of the urachus, CRS and HIPEC with open bladder. Diagnostic laparoscopy was not performed in 22/48 (46%) patients (palliative 5x; primary resection elsewhere 4x; large tumor with mucinous fluid (? 8cm) 3x; small, presumed benign tumor (? 2cm) 3x; before 2001 7x).

Results

In total, 37 patients who had UraC received treatment with curative intent (28 local excision only and 9 CRS with HIPEC). Median follow-up for the 9 HIPEC patients was 33 months (IQR 59 months) and 6/9 (67%) HIPEC patients still have no signs of recurrence after median follow-up of 53 months (IQR 75 months) (see Table). After HIPEC, two patients had postoperative adverse events requiring intervention (grade3). Disease specific survival for the patients treated with HIPEC for limited PC was comparable to the patients who had local excision only and was superior to the metastatic UraC patients (Plog-rank = 0.034).

Conclusions

Laparoscopy can reliably detect limited PC in patients with UraC without radiological signs of metastasis. If limited PC is present, HIPEC represents a curative treatment with favorable oncological outcome and acceptable toxicity.

Funding

none