Gleason score down and upgrading at radical prostatectomy in targeted vs. systematic prostate biopsy: Findings from an institutional cohort.

BACKGROUND

Accurate Gleason score (GS)/International Society of Urological Pathology (ISUP) Grade Group (GG) assessment in prostate cancer (PCa) is crucial for risk stratification and treatment. Multiparametric magnetic resonance imaging (mpMRI) and targeted biopsies (TPBx) have enhanced PCa detection, but their accuracy compared to systematic biopsies (SPBx) is under discussion. This study investigates GS/GG concordance between prostate biopsies (TPBx and SPBx) and radical prostatectomy (RP) specimens, evaluating rates and factors associated with GS/GG upgrading and downgrading.

MATERIALS AND METHODS

A retrospective analysis of 100 patients with PI-RADS score > 3 lesions who underwent SPBx, with or without TPBx, followed by RP for clinically significant prostate cancer (csPCa) was performed.

RESULTS

csPCa diagnosis was made by SPBx alone in 9/100 (9 %) cases, TPBx alone in 1/100 (1 %), and TPBx combined with SPBx in 90/100 (90 %). In the TPBx group, 76/90 (84.4 %) patients presented concordant GS/GG between biopsy and RP, while 14/90 (15.6 %) showed lower GS/GG at RP. In the SPBx group, 88/90 (97.8 %) presented concordant GS/GG, while 2/90 (2.2 %) showed higher GS at RP.

CONCLUSIONS

Our study highlights potential downgrading risk associated with TPBx alone, particularly in patients with initial GS of 4 + 4/GG4. While this has minimal implications for high-risk PCa, it raises concerns about potential overdiagnosis and overtreatment in men eligible for active surveillance (AS) who may be downgraded from intermediate-risk to low-risk or favourable intermediate-risk categories. This underscores the importance of using both TPBx and SPBx for PCa diagnosis and risk assessment.