Risk factors for local recurrence of rectal cancer after curative surgery: A single-center retrospective study.

Purpose: Approximately 7% of patients with rectal cancer experience local recurrence within 5 years of curative surgery. A positive circumferential resection margin (CRM) is among the most significant risk factors. Other reported risk factors include histopathologic type, anastomotic leakage, positive distal margins, and more recently, the anterior localization of the tumor. In this retrospective cohort study, we aimed to assess risk factors for local recurrence in our institution, with a focus on tumor localization as an independent negative predictive factor.

Patients and methods: From 2007 to 2018, all patients with stage II or III rectal cancer were included in this study. Patients underwent neoadjuvant chemoradiotherapy followed by surgical resection with total mesorectal excision. The tumor's anterior or posterior localization was assessed by preoperative endosonography or magnetic resonance imaging. Risk factors for local recurrence were assessed using univariate and multivariate regression analyses.

Results: A total of 128 patients were included. The 3-year and 5-year local recurrence rates were 4.7% and 7%, respectively. In univariate and multivariate analyses, the histologic type of a poorly differentiated tumor (P=0.001) and a positive CRM (P=0.001) were correlated with local recurrence. Tumor localization (anterior or posterior) was not identified as a statistically significant factor associated with local recurrence.

Conclusion: Positive CRM and a poorly differentiated tumor histological subtype were found to be independent risk factors for local recurrence. In contrast to previous findings, anterior localization was not identified as an independent risk factor for local recurrence in our patient cohort.