Surgical treatment of peritoneal carcinomatosis from well-differentiated digestive endocrine carcinomas

The presence of peritoneal carcinomatosis (PC) in association with endocrine carcinomas (EC) is generally considered to have no impact on life expectancy, contrary to liver metastases. This study was aimed at assessing the actual prognostic impact of PC and to evaluate a new treatment with respect to survival times.

Among 111 patients undergoing surgery for progressive, well-differentiated EC, 37 (33%) presented a histologically proven PC, with synchronous liver metastases in 36 of them. The origin was ileal or appendiceal (carcinoid tumors) in at least 81% of cases. The patients were divided into 2 groups. Patients in group 1 (n = 20) could not undergo complete resection of PC, while those in group 2 (n = 17) underwent complete cytoreductive surgery, followed by immediate intraperitoneal chemotherapy. Partial hepatectomy was performed in 65% of patients in group 2. The median follow-up was 6.9 years.

There was no postoperative mortality, and the morbidity rate was 47%. In group 1, 15 of the 20 patients died (5-year survival rate, 40.9%). Deaths were caused either by liver failure (60% of patients) or bowel obstruction from PC (40%). In group 2, six of the 17 patients died (5-year survival rate, 66.2%; P = .007). These patients died of liver failure (n = 4, 23.5%), bowel obstruction (n = 1, 5.8%), and cerebral hemorrhage (n = 1, 5.8%).

PC associated with EC is not a rare event; it is mainly caused by carcinoid tumors and is always associated with liver metastases. When present, PC is the direct cause of death in 40% of patients if no specific treatment is undertaken. Treatment of PC with maximal cytoreductive surgery and immediate intraperitoneal chemotherapy appears promising, even though it can only be considered as palliative.