Risk Stratification of prostate imaging reporting and data system (PI-RADS 3) lesions based on mean ADC values.

Motivation: PI-RADS 3 lesions have low cancer-positive rates, resulting in many unnecessary biopsies. Goal(s): This study investigates whether quantitative ADC measurements improve the classification of PI-RADS 3 lesions as cancerous or non-cancerous. Approach: Prostate MRI scans from 01/2017 to 10/2024 were analyzed. Of 1074 PI-RADS 3 lesions, final analysis included 152 PZ lesions and 75 TZ lesions. Results: Final analysis showed significant differences in mADC in PZ (cut-off: 920×10⁻⁶ mm²/sec) and TZ (cut-off: 610 mm2/sec) and TZ PSA density (P <0.001, AUC: 0.723). Combined analysis of mADC values and PSA density gives an AUC of 0.81. Impact: The results show that mean ADC values could help differentiate between cancers and non-cancers in PZ and TZ PI-RADS 3 lesions.