Macroscopic serosal invasion and small tumor size as independent prognostic factors in stage IIA colon cancer.

ABSTRACT

BACKGROUND: This study aimed to investigate the prognostic factors of patients with stage IIA (T3N0M0) colon cancer in terms of macroscopic serosal invasion and small tumor size. METHODS: We enrolled 375 stage IIA colon cancer patients who underwent curative resection between January 2004 and December 2011. Macroscopic serosal invasion was defined as tumor nodules or colloid changes protruding the surface of the serosa. The clinicopathologic characteristics were analyzed to identify independent prognostic factors. RESULTS: The median follow-up was 47 months (range, 1-90 months). On multivariate survival analysis, macroscopic serosal invasion (adjusted hazard ratio [HR] = 4.750; p = 0.013), tumor size < 5 cm (adjusted HR = 3.112, p = 0.009), perineural invasion (adjusted HR = 3.528; p = 0.002), < 12 retrieved lymph nodes (adjusted HR = 4.257; p = 0.002), and localized perforation (adjusted HR = 7.666; p = 0.008) were independent risk factors for recurrence. CONCLUSION: We found novel prognostic factors of stage IIA colon cancer, including macroscopic serosal invasion and small tumor size (< 5 cm). Further studies are needed to evaluate the benefit of adjuvant chemotherapy in patients with these prognostic factors.