Objective: This study aims to improve the accuracy of diagnosing prostate cancer by comparing biopsy samples obtained via transrectal ultrasonography (TRUS) for lesions identified using diffusion-weighted MRI (DW-MRI) and multiparametric prostate MRI (Mp-MRI).

Materials and Methods: Individuals with tPSA values between 2.5 and 20 ng/ml and no previous biopsy were divided into three groups of 50 patients each. 1st group: 12-core needle biopsy guided by TRUS. 2nd group: DW-MRI before biopsy under TRUS guidance. Extra samples from MRI-identified lesions plus 12-core biopsy. Pathological findings compared to evaluate MRI's accuracy. 3rd group: Mp-MRI before biopsy under TRUS guidance. Extra samples from PIRADS 2 and above lesions plus 12-core biopsy. Pathological results analyzed to assess Mp-MRI's accuracy.

Results: In Group 1, TRUS-guided biopsy diagnosed prostate cancer in 8 out of 50 patients (16%). In Group 2, 13 out of 50 patients (26%) were diagnosed. MRI-identified lesions revealed cancer in 10 patients (76.9%). MRI showed no suspicious areas in 3 patients. Among 37 patients without cancer, one had a suspicious MRI lesion, but the biopsy was negative. In Group 3, prostate cancer was detected in 18 out of 50 patients (36%). MRI-identified lesions revealed cancer in 16 patients (88.8%). In 2 patients, tumors were found outside MRI-identified areas. TRUS and DW-MRI guided biopsies showed significant results (p=0.0001). DW-MRI sensitivity was 77%, and specificity was 97%. Mp-MRI sensitivity was 88.9%, and specificity was 6.25%.

Conclusion: Conducting DW-MRI and Mp-MRI before a prostate biopsy increases diagnosis rates which is better than TRUS-guided biopsy alone.