Association of resection margin distance with anastomotic recurrence in stage I-III colon cancer: data from the National Colorectal Cancer Cohort (NCRCC) study in China.

PURPOSE: Few studies have focused on anastomotic recurrence (AR) in colon cancer. This study aimed to clarify the association of resection margin distance with AR and compare the prognosis with nonanastomotic local recurrence (NAR).

METHODS: This retrospective cohort study included the clinical data of patients who underwent radical colon cancer surgery between January 1, 2009, and December 31, 2019.

RESULTS: A total of 1958 colon cancer patients were included in the study. 34 of whom (1.7%) had AR and 105 of whom (5.4%) had NAR. Multivariate analysis revealed that the lower distal resection margin distance, advanced N stage, and number of lymph nodes dissected were risk factors for AR. In the proximal resection margin, the risk of AR was lowest at a distance of 6 cm or greater, with a 3-year rate of 1.3%. In the distal resection margin, the 3-year AR risk increased rapidly if the distance was less than 3 cm. The prognosis of patients in the AR group was similar to that of patients in the NAR group, regardless of synchronous distant metastases. Furthermore, the radical surgery rate for AR was significantly higher than that for NAR, but the prognosis of AR was comparable to that of NAR.

CONCLUSIONS: The distal resection margin distance, advanced N stage, and less number of lymph nodes dissected are associated with AR of colon cancer. The prognosis of patients with AR was similar to that of patients with NAR.

TRIAL REGISTRATION: Clinical Trial Numbers NCT04074538 ( clinicaltrials.gov ), August 26, 2019, registered, retrospectively registered.