Incidence, patterns of failure, and prognosis of perforated colorectal cancers in a well-defined population.

Introduction: Few population-based studies investigate perforated colorectal cancers. This study was designed to compare the epidemiologic characteristics of perforated CRC with those of uncomplicated CRC and to determine patterns of failure and prognosis in a well-defined French population.

Methods: Between 1976 and 2000, 89 patients who received an emergency operation caused by perforation and 5,462 who underwent elective surgery were registered in the digestive cancer registry of Burgundy (France).

Results: Perforated colorectal cancers represented 1.6 percent of registered colorectal cancers. The five-year cumulative local recurrence rate was higher for perforated (15.7 percent) than for uncomplicated cancers (7.8 percent; P = 0.021), as well as for the peritoneal carcinomatosis rate (respectively 13.8 and 6.3 percent; P = 0.036). In multivariate analysis, perforation was an independent risk factor for local recurrence or peritoneal carcinomatosis (odds ratio, 2.17; P = 0.004). Operative mortality was higher among perforated cancers (20.2 percent) than after elective surgery (6.6 percent, P < 0.001). The five-year relative survival rates were 37 percent after emergency surgery and 49.2 percent after elective surgery (P = 0.036). After adjustment for sex, stage, and age, perforation remained significantly associated with a poor prognosis. After exclusion of operative mortality, perforation was no more significant.

Conclusions: Perforation is a rare complication of colorectal cancer. The prognosis is poor because of high operative mortality and high risk of local recurrence and peritoneal carcinomatosis.