Patterns of recurrence of obstructing colon cancers after surgery for cure: a population-based study.

Aim: Little is known about patterns of recurrence in obstructing colon cancer (OCC) at a population level. The aim of this study was to determine the risk of recurrence following potentially curative surgery in OCC compared with that in uncomplicated colon cancer (CC).

Method: Data were obtained from the population-based digestive cancer registry of Burgundy (France). Local and distant failure rates were calculated using actuarial methods. A multivariate analysis was performed using a Cox model.

Results: Obstructing colon cancer represented 8.5% of all colon cancers resected with curative intent (n = 3375). The 5-year cumulative local recurrence rate was 14.2% for OCC and 7.6% for nonobstructing CC (P = 0.003). In the multivariate analysis, obstruction was an independent risk factor for local recurrence [hazard ratio 1.53 (1.01-2.34), P = 0.047]. The risk of local recurrence increased with advanced stage and age at diagnosis. The 5-year cumulative rate for distant metastases was also higher in OCC than in nonobstructing CC (36.1 vs 23.1%; P < 0.001). The relative risk of distant metastasis was borderline significant in the multivariate analysis [hazard ratio 1.25 (0.99-1.59), P = 0.057]. Stage at diagnosis, macroscopic type of growth, period of diagnosis and sex were also significant prognostic factors. Age and subsite were not significant in the multivariate analysis.

Conclusion: It is possible to conduct special surveys in population-based registries to determine the recurrence rate of CC. Recurrence remains a substantial problem and is more frequent in OCC than in nonobstructing CC. Efforts must be made to diagnose CC earlier. Mass screening is a promising approach.