Perineural invasion on prostate needle biopsy: An independent predictor offinal pathologic stage

Objectives, To examine the significance of perineural invasion (PNI) in pre dicting pathologic findings in patients treated by radical prostatectomy, b ecause a recent study concluded that PNI on needle biopsy has no independen t predictive value. Methods; Between 1993 and 1998, radical prostatectomy was performed in 319 consecutive patients. Prostate needle biopsies were reviewed in all cases. We compared PNI with other preoperative parameters, including digital recta l examination, PSA, and biopsy Gleason score, for the ability to predict tu mor stage. Clinical records and pathologic findings were reviewed for all c ases. Tumor stage was defined as either pT2 (organ confined) or pT3 (extrap rostatic extension and/or;seminal vesicle invasion). Results. The median age was 61.4 years (range 40 to 75.6). Seventy-two perc ent of the 95 men with nonpalpable disease and 67% of the 224 men with palp able disease had organ-confined prostate cancer on final pathologic staging . Of 205 men with a Gleason score on biopsy of 6 or less, 159 (78%) had org an-confined disease compared with 59 (52%) of 114 with a Gleason score of 7 to 9 (P < 0.001, chi-square test). PNI was identified in 77 (24%) of 319 p atients, with 83% specificity and 40% sensitivity for Stage pT3 disease (od ds ratio 3.49). Of men with pT3 disease on final pathologic staging, 18%, 2 7%, and 56% had preoperative PSA levels of 0 to 4, more than 4 to 10, and g reater,than 10 ng/mL, respectively (P <0.001, Mantel-Haenszel chi-square te st). On multivariate analysis, PNI (P = 0.0031), PSA (P = 0.0004), and Glea son score (P = 0.0003) independently predicted stage (pT3 disease). Conclusions. PNI is an important preoperative predictor of pathologic stage and should be reported when adenocarcinoma is diagnosed on prostate needle biopsies. (C) 1999, Elsevier Science Inc.