The prognostic impact of perineural invasion on post-recurrence survival in locally advanced rectal adenocarcinoma patients with early recurrence

Perineural invasion, an independent prognostic factor in colorectal cancer, has been implicated in influencing patient survival. This study delves into the clinical significance of perineural invasion in locally advanced rectal adenocarcinoma patients with early recurrence. This retrospective analysis encompassed 303 locally advanced rectal adenocarcinoma patients with early recurrence between 2013 and 2021. The patients were stratified based on the presence or absence of perineural invasion. To evaluate the factors influencing prognosis, a multivariate Cox proportional hazards model was employed. Kaplan-Meier analysis, coupled with the log-rank test, was utilized to compare post-recurrence survival across different groups. Among the 303 patients with early recurrence, 81 (26.7%) exhibited perineural invasion. Multivariate analysis revealed that perineural invasion (HR = 1.451, 95%CI, 1.007–2.090, P = 0.046) was an independent prognostic factor for 5-year post-recurrence survival. Patients with perineural invasion had a significantly worse 5-year post-recurrence survival(28.3% vs. 49.1%, P < 0.001). In the PNI-positive subgroup, the rate of liver metastasis (HR = 2.089,95%CI, 1.136–3.842, P = 0.018) emerged as independent prognostic factors for 5-year post-recurrence survival. Perineural invasion stands as an independent prognostic factor for 5-year post-recurrence survival in locally advanced rectal adenocarcinoma patients with early recurrence who have undergone neoadjuvant therapy and radical surgery. These findings underscore the critical role of perineural invasion in guiding therapeutic strategies for early recurrence patients.