Role of Multiparametric MRI and Transrectal Ultrasound with Color Doppler in Prostatic Lesions: Correlation with TRUS-Guided Biopsy — A Prospective Observational Study

Abstract

Background: Prostate cancer is the second most common malignancy in men worldwide, and its early, accurate detection remains a diagnostic challenge. Transrectal ultrasound (TRUS) has long been the primary imaging tool; however, its standalone sensitivity is limited. Multiparametric MRI (mpMRI) integrates morphological and functional sequences to provide more comprehensive lesion characterisation. This study evaluated how mpMRI and TRUS with color Doppler perform individually and in combination for detecting prostatic lesions, using TRUS-guided biopsy histopathology as the reference standard. Methods: Twenty-five male patients aged ≥50 years with elevated PSA and/or abnormal digital rectal examination (DRE) were enrolled. Each participant underwent TRUS with color Doppler followed by mpMRI; lesions were scored using PI-RADS v2.1. TRUS-guided biopsy served as the histopathological reference. Results: Biopsy confirmed prostate adenocarcinoma in 14 of 25 patients (56%); clinically significant disease (Gleason Grade Group ≥2) was present in 11 (44%). mpMRI achieved sensitivity 85.7%, specificity 81.8%, and accuracy 84.0% (AUC 0.847). TRUS with color Doppler achieved sensitivity 64.3%, specificity 63.6%, and accuracy 64.0% (AUC 0.640). Combined imaging reached sensitivity 92.9%, specificity 81.8%, and accuracy 88.0%. PI-RADS score correlated strongly with histopathological Grade Group (Spearman's rho = 0.74; p < 0.001). Conclusion: mpMRI substantially outperforms TRUS with color Doppler in detection and characterisation of prostatic malignancy. Combined imaging achieves the highest sensitivity and NPV, and is recommended as the pre-biopsy evaluation strategy. PI-RADS v2.1 reliably stratifies cancer risk and correlates with tumour grade.