Does perineural invasion on prostate biopsy predict adverse prostatectomy outcomes?

UROLOGICAL SURVEY

Pathology

Does perineural invasion on prostate biopsy predict adverse prostatectomy outcomes?

Loeb S, Epstein JI, Humphreys EB, Walsh PC

James Buchanan Brady Urological Institute and the Department of Urology, Johns Hopkins Medical Institutions, Baltimore, MD, USA

BJU Int. 2009 Aug 19. Epub ahead of print

OBJECTIVE: To determine the relationship between perineural invasion (PNI) on prostate biopsy and radical prostatectomy (RP) outcomes in a contemporary RP series, as there is conflicting evidence on the prognostic significance of PNI in prostate needle biopsy specimens.

PATIENTS AND METHODS: From 2002 to 2007, 1256 men had RP by one surgeon. Multivariable logistic regression and Cox proportional hazards models were used to examine the relationship of PNI with pathological tumour features and biochemical progression, respectively, after adjusting for prostate-specific antigen level, clinical stage and biopsy Gleason score. Additional Cox models were used to examine the relationship between nerve-sparing and biochemical progression among men with PNI.

RESULTS: PNI was found in 188 (15%) patients, and was significantly associated with aggressive pathology and biochemical progression. On multivariate analysis, PNI was significantly associated with extraprostatic extension and seminal vesicle invasion (P < 0.001). Biochemical progression occurred in 10.5% of patients with PNI, vs 3.5% of those without PNI (unadjusted hazard ratio 3.12, 95% confidence interval 1.77-5.52, P < 0.001). However, PNI was not a significant independent predictor of biochemical progression on multivariate analysis. Finally, nerve-sparing did not adversely affect biochemical progression even among men with PNI.

CONCLUSION: PNI is an independent risk factor for aggressive pathology features and a non-independent risk factor for biochemical progression after RP. However, bilateral nerve-sparing surgery did not compromise the oncological outcomes for patients with PNI on biopsy.

Editorial Comment

The significance of perineural invasion by carcinoma in needle prostatic biopsies is controversial (1,2). Presence of perineural invasion in needle prostatic biopsies may influence the indication of resection of neurovascular bundle. Loeb's et al. study showed that perineural invasion on prostate biopsy was not a significant independent predictor of biochemical progression on multivariate analysis and nerve-sparing surgery did not adversely affect biochemical progression even among men with perineural invasion.

In a recent study, we found that perineural invasion in needle prostatic biopsies significantly predicted prostatectomy stage > pT2 in univariate (p < 0.01) but not in multivariate analysis (p = 0.38). In multivariate analysis preoperative PSA, Gleason grading and percentage of linear extent of cancer in mm in the needle biopsy were the significant variables predictive of > pT2.

We agree with Loeb's et al. conclusion that nerve-sparing surgery does not adversely affect biochemical progression even among men with perineural invasion.

Dr. Athanase Billis

Full-Professor of Pathology

State University of Campinas, Unicamp

Campinas, São Paulo, Brazil

E-mail: [e-mail]

• 1. Bastacky SI, Walsh PC, Epstein JI: Relationship between perineural tumor invasion on needle biopsy and radical prostatectomy capsular penetration in clinical stage B adenocarcinoma of the prostate. Am J Surg Pathol. 1993; 17: 336-41.
• 2. Egan AJM, Bostwick DG: Prediction of extraprostatic extension of prostate cancer based on needle biopsy findings: Perineural invasion lacks significance on multivariate analysis. Am J Surg Pathol. 1997; 21: 1496-500.

Publication Dates

• Publication in this collection
  07 Dec 2009
• Date of issue
  Oct 2009