Perineural and lymphovascular invasion as histologic predictors of a 5-year local recurrence after curative resection of stages II and III rectal cancer

Background: Distinguishing predictors of local recurrence after surgery is important following curative resection of rectal cancer. Objectives: This study aimed to evaluate the correlation between perineural and lymphovascular invasion with local recurrence after curative resection of rectal cancer. Design: Prospective Cohort Study. Patient and Methods: Patients with stages II and III rectal cancer operated on between January 2011 and December 2015 were included. Data including demographic information and pathologic characteristics of the primary tumor, including perineural and lymphovascular features, were collected. The patients were followed-up for at least 5 years for any evidence of tumor recurrence. Main Outcome Measure: Perineural invasion (PNI) and Lymphovascular invasion (LVI). Sample Size: 202 patients (including 77 women and 125 men). Results: PNI and LVI were found in the histologic features of the tumors of 34 (16.8%) and 56 (27.7%) patients, respectively. 85.3% of the patients with PNI and 67.9% with LVI had developed recurrence within 5 years after curative surgery. Twenty-four patients had concurrent PNI and LVI, which showed a recurrence rate of 87.5%. Conclusion: This study found a significant correlation between tumor recurrence and PNI or LVI in male patients with stage II or III rectal cancer. In addition, a significant relationship was found between PNI and tumor recurrence in female patients; however, there was no significant correlation between LVI and tumor recurrence in these patients. Limitations: Limited sample size. Conflict of Interest: The authors have no conflict of interest to declare.