Pelvic lymph node dissection (PLND) is the most accurate procedure for lymph node (LN) staging in prostate cancer (PCa) patients. LN sectioning and hematoxylin and eosin (H&E) staining of at least one slice remains the gold standard for LN evaluation, potentially leading to misdetection of small metastatic focus. Entire LN analysis is possible with One-Step Nucleic Acid Amplification (OSNA) by detecting cytokeratin 19 (CK19) mRNA as a surrogate for LN invasion. This study aimed to compare postoperative performance of OSNA pooling with conventional H&E staining for pathological LN detection in PCa patients. POPCORN was an observational, prospective, and multicenter study of patients with PCa who underwent PLND. Dissected LNs were analyzed by both methods. This study included 2503 LNs from 131 patients, showing no statistically significant differences in pathological LN detection. Concordance between methods was high (93.9%), as were specificity (96.6%) and negative predictive value (96.6%) of OSNA pooling. The measure of agreement (Cohen’s Kappa [κ]) was 0.70. Only eight (6.1%) discordances were observed, including four misdetections from each method. Results showed a high concordance between OSNA pooling and H&E staining, suggesting that OSNA pooling may be a good alternative to H&E staining to detect LN metastases in PCa patients.

Background: Active surveillance (AS) is increasingly considered for selected patients with International Society of Urological Pathology (ISUP) Grade Group (GG) 2 prostate cancer. However, candidate selection remains controversial due to histological heterogeneity and the risk of harboring adverse pathology (AP). We aimed to identify preoperative clinical, multiparametric magnetic resonance imaging (mpMRI), and histological predictors of AP, biochemical recurrence (BCR), and postoperative PSMA PET/CT positivity in men with biopsy-confirmed ISUP GG 2 disease undergoing robotic-assisted radical prostatectomy (RARP). Methods: We retrospectively analyzed 127 consecutive patients with biopsy-proven ISUP GG 2 prostate adenocarcinoma from a prospective single-center RARP database (2012–2024). All patients underwent pre-biopsy 3T mpMRI and systematic plus software-fusion targeted biopsies, with diagnostic specimens strictly lacking cribriform architecture or intraductal carcinoma. AP was defined as pathological stage ≥ pT3 and/or ISUP GG upgrading to ≥3 in the final surgical specimen. BCR was defined as two consecutive postoperative PSA measurements ≥ 0.2 ng/mL. Patients with BCR underwent PSMA PET/CT restaging. Univariable and multivariable logistic regression analyses evaluated independent preoperative predictors of AP, incorporating separate models for ≥10% and ≥15 biopsy Gleason pattern 4 thresholds to prevent collinearity. Model performance was evaluated using the area under the receiver operating characteristic curve (AUC) and Hosmer–Lemeshow calibration tests. Results: Median patient age was 63.2 years, median PSA was 7.6 ng/mL, and median PSA density (PSAD) was 0.18 ng/mL. PI-RADS ≥ 4 lesions were identified in 71.6% of patients, and median biopsy pattern 4 proportion was 21.1%. Overall, AP occurred in 39 of 127 patients (30.7%), driven by ISUP upgrading to GG ≥ 3 in 21.3% (n = 27) and upstaging to ≥pT3 in 17.3% (n = 22). No undergrading was observed. On univariable analysis, PSA (p = 0.028), PSAD (p = 0.011), and biopsy pattern 4 proportion ≥ 10% (p = 0.042) and ≥15% (p = 0.027) were significantly associated with AP. On multivariable analysis, PSAD (OR 6.75, 95% CI 3.51–12.87, p = 0.005) and biopsy pattern 4 proportion ≥ 10% (OR 2.54, 95% CI 1.15–6.54, p = 0.036) or ≥15% (OR 2.74, 95% CI 1.06–6.06, p = 0.023) remained independent predictors of AP. The final multivariable model demonstrated solid discrimination (AUC = 0.78, 95% CI 0.71–0.85) and satisfactory calibration (p = 0.42). At a mean follow-up of 32.3 months, BCR occurred in 23 patients (18.1%; 3-year recurrence-free survival: 81.3%). Restaging PSMA PET/CT was positive in 8 of 23 recurrences (34.8%; three local, four regional nodal, one solitary bone). Neither clinical nor radiological parameters independently predicted BCR or PSMA PET/CT positivity. Conclusions: Biopsy Gleason pattern 4 extent (<10% and <15%) and PSAD are the strongest independent preoperative predictors of organ-confined, non-upgraded pathology in ISUP GG 2 prostate cancer. Combining a low pattern 4 burden (<10%, or up to 15% in highly selected cases) with a low PSAD provides objective parameters to refine “favorable intermediate-risk” stratification by identifying patients with a lower probability of adverse pathological features.

A prospective analysis was conducted to assess the incidence of inflammatory features reported in targeted biopsies of 531 MRI-suspicious lesions with prostate imaging-reporting and data system (PI-RADS) scores of 3 to 5 in 364 men suspected of having PCa. The incidence of inflammatory features in the MRI-suspicious lesions without PCa was 69.6%, compared to 48.1% in those with PCa (p < 0.001). Among the suspicious lesions without PCa, the incidence of inflammatory features ranged from 68.6% to 71.2% across the PI-RADS categories (p = 0.870). Mild chronic prostatitis increased with higher PI-RADS scores, while acute prostatitis decreased, and granulomatous prostatitis was exclusively observed in patients with PI-RADS scores of 4 and 5. The incidence of inflammatory features in the lesions with insignificant PCa (grade group 1) was 66.7%, compared to 42.7% in those with significant PCa (grade group 2 to 5; p = 0.027). The detection of inflammatory features in MRI-suspicious lesions was identified as an independent predictor of a lower likelihood of significant PCa detection, with an odds ratio (OR) of 0.326 (95% CI 0.196-0.541). Mild chronic prostatitis was the only type of prostatitis which was an independent predictor of a lower likelihood of significant PCa, with an OR of 0.398 (95% CI 0.268-0.590). These data suggest that inflammatory features may be considered to be mimickers of significant PCa on MRI.