ABSTRACT

The impact of perineural invasion (PNI) finding in prostate needle biopsy on extraprostatic extension and grade and seminal vesicle invasion were investigated in this study.

Prostate cancer patients diagnosed with extraprostatic extension (PT3a, group 1) and seminal vesicle invasion (PT3b, group 2) after radical retropubic prostatectomy (RRP) between 2005-2014 were evaluated retrospectively. Group 1 was further divided in two subgroups as patients with focal (group 1a) and diffuse (group 1b) extraprostatic extension. PSA, PSA density, prostate needle biopsy findings (Gleason score, core number and percent and PNI) and RRP final pathological findings (Gleason score, tumor volume, positive surgical margin and positive lymph nodes) were compared between groups.

A total of 129 patients were included; 92 in group 1 (49 in group 1a and 43 in group 1b) and 37 in group 2. Patients in group 2 had significantly higher Gleason scores, tumor percent and PNI presence when compared to patients in group 1 (7.2±0.8 vs. 6.7±0.6; 60.9±29.9% vs. 48.8±31.6%; 62.2% vs. 29.4%; p<0.05). Presence of PNI was significantly higher in group 1b compared to group1a (39.5% vs. 20.4%; p<0.05).

It was demonstrated that there was a significant relationship between the presence of PNI and both the grade of extraprostatic extension in PT3a disease and the presence of PT3b disease. Risk of diffuse extraprostatic extension and seminal vesicle invasion should be kept in mind especially while planning nerve sparing surgery for patients with PNI in prostate biopsies.