Clinical Significance of Perineural Invasion in Men with Grade Group 1 Prostate Cancer on Active Surveillance.

We aimed to evaluate the clinical significance of perineural invasion (PNI) in men on active surveillance (AS) for Grade Group (GG) 1 prostate cancer (PCa).

We identified 1969 men with GG1 PCa and at least 1 follow-up biopsy. A time-dependent Cox model and a logistic regression model were used to assess the association between biopsy-detected PNI and grade reclassification (GR) (defined as the detection of GG≥2 PCa on a surveillance biopsy), and adverse pathology (AP) (defined as GG≥3, seminal vesicle invasion, lymph node involvement) at radical prostatectomy (RP), respectively.

The 198 men with PNI detected during AS had lower rates of GR-free survival than those without PNI (p<0.001). On multivariable analysis PNI was significantly associated with GR (HR 3.25, 95% CI 2.54-4.16, p<0.001); an association that persisted in the multiparametric magnetic resonance imaging (mpMRI) subset. At RP, men with biopsy-detected PNI had more extraprostatic extension than men without PNI (Relative Risk 1.71, 95% CI 1.15-2.56). However, on multivariable analysis biopsy-detected PNI was not associated with AP (OR 0.68, 95% CI 0.27-1.68, p=0.40) and these patients did not exhibit more biochemical recurrence at 5 years (p>0.05).

PNI during AS was associated with GR. At RP biopsy-detected PNI patients exhibited more EPE but biopsy-detected PNI was not independently associated with more AP. In addition, these patients did not have more biochemical recurrence during follow-up. PNI should not preclude GG1 patients from AS but they may warrant more stringent monitoring.

The Journal of urology. 2022 Sep 08 [Epub ahead of print]

Claire M de la Calle, Mufaddal M Mamawala, Patricia Landis, Katarzyna J Macura, Bruce J Trock, Jonathan I Epstein, Christian P Pavlovich

The James Buchanan Brady Urological Institute and Department of Urology, Johns Hopkins University School of Medicine, Baltimore, Maryland.