Clinical Significance of Perineural Invasion in Prostate Needle Biopsy in Patients Diagnosed with Extraprostatic Extension and Seminal Vesicle Invasion after Radical Prostatectomy

Effects of perineural invasion in prostate needle biopsy on tumor grade and biochemical recurrence rates after radical prostatectomy

To predict local invasive disease before retropubic radical prostatectomy (RRP), the correlation of perineural invasion (PNI) on prostate needle biopsy (PNB) and RRP pathology data and the effect of PNI on biochemical recurrence (BR) were researched. For patients with RRP performed between 2005 and 2014, predictive and pathologic prognostic factors were assessed. Initially all and D'Amico intermediate-risk group patients were comparatively assessed in terms of being T2 or T3 stage on RRP pathology, positive or negative for PNI presence on PNB and positive or negative BR situation. Additionally the effect of PNI presence on recurrence-free survival (RFS) rate was investigated. When all patients are investigated, multivariate analysis observed that in T3 patients PSA, PNB Gleason score (GS) and tumor percentage were significantly higher; in PNI positive patients PNB GS, core number and tumor percentage were significantly higher and in BR positive patients PNB PNI positivity and core number were significantly higher compared to T2, PNI negative and BR negative patients, separately (p < 0.05). When D'Amico intermediate-risk patients are evaluated, for T3 patients PSA and PNB tumor percentage; for PNI positive patients PNB core number and tumor percentage; and for BR positive patients PNB PNI positivity were significantly higher compared to T2, PNI negative and BR negative patients, separately (p < 0.05). Mean RFS in the whole patient group was 56.4 ± 4.2 months for PNI positive and 96.1 ± 5.7 months for negative groups. In the intermediate-risk group, mean RFS was 53.7 ± 5.1 months for PNI positive and 100.3 ± 7.7 months for negative groups (p < 0.001). PNI positivity on PNB was shown to be an important predictive factor for increased T3 disease and BR rates and reduced RFS.