Biopsy Gleason pattern 4 burden refines preoperative risk stratification in prostate cancer

Area of Science:

• Urology
• Oncology
• Pathology

Background:

• Prostate cancer risk stratification relies on Gleason grade group (GG).
• Accurate prediction of adverse pathology and biochemical recurrence (BCR) is crucial for treatment planning in intermediate- and high-risk prostate cancer.
• The prognostic role of specific Gleason pattern 4 (GP4) burden requires further evaluation.

Purpose of the Study:

• To assess the prognostic significance of biopsy-based GP4 burden.
• To evaluate GP4's predictive value in a diverse patient cohort undergoing radical prostatectomy (RP).
• To compare GP4-based risk stratification with existing models.

Main Methods:

• Retrospective analysis of 368 men with GG 2-4 prostate cancer treated with RP.
• Quantification of GP4 burden using biopsy metrics.
• Evaluation of associations with adverse surgical pathology (ASP) and 3-year BCR using multivariable regression and concordance index.
• Development and comparison of a point-based pattern 4 risk score (P4RS).

Main Results:

• The cohort was diverse (76% Black or Hispanic/Latino).
• ASP occurred in 38% and 3-year BCR in 17% of patients.
• Increased GP4 length correlated with higher ASP and BCR risk.
• GP4 metrics improved BCR prediction (concordance index 0.716-0.723) compared to GG (0.690).
• The P4RS showed superior discrimination (concordance index 0.728).

Conclusions:

• Biopsy-based absolute GP4 burden, especially total length, offers significant prognostic information.
• GP4 burden improves risk stratification for adverse pathology and early oncologic outcomes post-prostatectomy.
• This metric enhances prediction beyond current Gleason grade group classifications.