Incidence and prognosis of synchronous colorectal carcinomatosis.

The aim of this article was to review the literature on synchronous peritoneal carcinomatosis (PC) from colorectal cancer. Synchronous PC of colorectal cancer origin is a rare disease with an incidence ranging from 4 to 7% of colorectal cancer patients and is exclusively peritoneal in half of cases. Synchronous PC is more frequently associated with primary tumors that are at an advanced stage. After macroscopically complete resection (R0/R1) of synchronous PC, without associated intraperitoneal chemotherapy, the 5-year survival rates range from 24 to 36%. Complete cytoreductive surgery plus intraperitoneal chemotherapy at the time of diagnosis is probably the best therapeutic option. If no intraperitoneal treatment can be given, no resection should be performed and an accurate description should be made. If a limited synchronous PC has been resected with the primary tumor without intraperitoneal treatment, the authors recommend a systematic second-look surgery in an experienced center.