Risk factors of recurrence in TNM stage I colorectal cancer

PURPOSE: TNM stage I colorectal cancer (CRC) can recur, although the recurrence rate is low. Few studies have evaluated the risk factors for TNM stage I CRC recurrence. This study aimed to evaluate the TNM stage I CRC recurrence rate, as well as risk factors for recurrence. METHODS: In this retrospective study, we reviewed the database of patients who had undergone surgery for TNM stage I CRC between November 2008 and December 2014 without receiving neoadjuvant therapy or transanal excision for rectal cancer. Our analysis included 173 patients. Primary lesions were found in the colon of 133 patients and in the rectum of 40 patients. RESULTS: The CRC recurrence rate was 2.9% (5 out of 173 patients). For colon cancer patients, tumor size was not associated with higher recurrence risk (P = 0.098). However, for rectal cancer patients, both tumor size (≥3 cm) and T stage were associated with higher recurrence risk (P = 0.046 and P = 0.046, respectively). Of the 5 recurrent cases, 1 patient exhibited disease progression despite treatment, 1 patient maintained stable disease status after recurrence treatment, and 3 patients had no evidence of a tumor after recurrence treatment. CONCLUSION: Our findings suggest that tumor size and T stage are predictors of stage I rectal cancer recurrence, and careful monitoring and follow-up of patients with larger tumors may be warranted.