The Effect of Perineural Invasion on Biochemical Recurrence-free Survival Following Nerve-sparing Radical Prostatectomy

Objective: Perineural invasion (PNI) is a histopathological finding which represents invasion of the nerves and surroundings by cancer cells.Several studies have reported that PNI in prostate cancer (PCa) is a poor prognostic factor.However, there are insufficient data in literature related to the use of PNI status in the biopsy at the stage of making a decision for nerve-sparing surgery.This research aimed to investigate the impact of PNI identified in prostate biopsies on the biochemical recurrence-free survival (RFS) in individuals who underwent nerve-sparing radical prostatectomy (RP) for PCa. Materials and Methods:The data of 972 patients who underwent nerve-sparing RP due to a clinically localized PCa diagnosis were retrospectively examined.Patients were divided into two groups as PNI (+) and PNI (-) according to PRI status in prostate biopsy pathology.Results: Evaluation was made of 747 patients with suitable data for analysis.PNI was determined in the prostate biopsy of 162 patients and not in the biopsies of 585 patients.The 5-year biochemical RFS rates were 90% for PNI (+) patients and 89.6% for the PNI (-) group, and the difference between the two groups was not statistically significant.When the PNI positive and negative groups were compared in respect of surgical margin positivity, the surgical margin was determined as positive in 42 (25.9%) of the group with PNI and in 84 (14.4%) of the group without PNI.Surgical margin positivity was determined to be statistically significantly greater in the PNI (+) group.Biochemical RFS rates were compared according to the surgical margin positivity status, and 5-year biochemical RFS was found to be 81.5% in those with surgical margin positivity and 91.6% in those with surgical margin negativity, no statistically meaningful distinction was found between the groups Conclusions: The findings of this study indicated that PNI determined in prostate biopsy did not affect 5-year RFS following nerve-sparing RP.