Recurrence risk analysis for stage II and III colorectal cancer, and the implications of diabetes mellitus as a risk factor for the recurrence of stage III colorectal cancer.

The present study investigated the risk factors for recurrence in patients with stage II-III colorectal cancer (CRC) who underwent colorectal surgery. Data from 232 patients with stage II and III CRC who underwent primary tumor resection were retrospectively analyzed. Univariate and multivariate analyses were performed to determine the risk factors for recurrence. The overall recurrence rate was 21.6% (n=50/232). Univariate Cox regression analysis identified diabetes mellitus (DM) (P=0.032) as a risk factor for recurrence. In addition, multivariate Cox regression analysis showed that DM was an independent risk factor for recurrence-free survival (RFS) (hazard ratio 2.40, P=0.016). The RFS curve obtained using the Kaplan-Meier method indicated that in patients with stage III colon cancer, the non-DM group demonstrated a significantly longer RFS than the DM group (P=0.012). In conclusion, the present study demonstrated that DM may be an independent risk factor for recurrence in patients undergoing curative resection for stage III CRC. Consequently, better postoperative therapy and careful monitoring might be required, especially in patients with stage III CRC and preoperative DM.