Nahuel Paesano, Violeta Catalá, Juan Camean, Tomás Eduardo Olmedo, Joaquín Ignacio Gurovich, Maximiliano Ringa, Berta Miró, Lucas Regis, Olga Mendez, Enrique Trilla, Juan Morote
Background: External validation of predictive models is needed in new populations after their implementation. Objective: We aimed to validate and compare the performance of the BCN-MRI PM and ERSPC-MRI PM in an Ibero-American population. Methods: We conducted a retrospective analysis of 540 men with suspected PCa who underwent MRI and prostate biopsy in 2025. Individual csPCa risk estimates were calculated using the online calculators for the BCN-MRI PM and ERSPC-MRI PM. The reference standard outcome was the rate of avoided biopsies. Calibration, discrimination of csPCa, net benefit, and clinical utility were analyzed with R software. Results: All participants underwent MRI and prostate biopsy. The median age was 66 years (95% CI 61-71). The overall csPCa detection rate was 55.7%. The BCN-MRI PM demonstrated good calibration, with close agreement between predicted and observed csPCa probabilities, whereas the ERSPC-MRI PM underestimated risk in the intermediate-probability range. Discrimination for csPCa was significantly better with the BCN-MRI PM (AUC, 0.807; 95% CI 0.771-0.843) than with the ERSPC-MRI PM (AUC, 0.764; 95% CI 0.724-0.803; p < 0.001). Decision curve analysis showed a greater net benefit for the BCN-MRI PM than for the ERSPC-MRI PM and the strategy of biopsying all men. Clinical utility curves demonstrated a more favorable balance between avoided biopsies and missed csPCa cases across threshold probabilities. At a sensitivity of 95%, the BCN-MRI PM achieved a specificity of 38.9% (95% CI, 32.5-45.1%) compared with 30.1% (95% CI, 24.6-35.7%) for the ERSPC-MRI PM, avoiding 21.5% and 16.3% of biopsies, respectively (p = 0.043). The performance of both models was also evaluated according to PI-RADS category and participating center. Conclusions: In this Ibero-American cohort, the BCN-MRI PM demonstrated superior calibration and overall clinical performance compared with the ERSPC-MRI PM.