The value of diffusion-weighted MR imaging combined with transrectal ultrasound for transrectal prostate biopsy

Abstract

To retrospectively analyze the clinical value of diffusion-weighted MR imaging in the detection of prostate cancer in suspected patients. Between January 2009 and December 2010, the 551 patients suspected as prostate cancer underwent prostate biopsy. Patients in group A were accepted to a transrectal ultrasound (TRUS) guided transrectal prostate biopsy (n = 410), while patients in group B were accepted to a diffusion weighted imaging (DWI) and TRUS jointly guided transrectal prostate biopsy (n = 141). The two groups were divided into 4 subgroups by prostate specific antigen (PSA) < 10 µg/L, 10 µg/L ≤ PSA < 20 µg/L, 20 µg/L ≤ PSA < 50 µg/L and PSA ≥ 50 µg/L. Then, the diagnostic rates of prostate biopsy guided by combination of DWI and TRUS with only TRUS were compared. The diagnostic rate of patients with PSA < 10 µg/L, 10 µg/L ≤ PSA < 20 µg/L, 20 µg/L ≤ PSA < 50 µg/L and PSA ≥ 50 µg/L were 12.1%, 31.1%, 48.0%, 91.2% in group A, and 23.7%, 35.5%, 66.7%, 96.3% in group B, respectively. In the patients with PSA less than 10 µg/L, there were significant differences in diagnostic rate between the two biopsy techniques (χ(2) = 4.405, P < 0.05). The combination of DWI and TRUS showed the potential to guide biopsy to cancer foci in patients suspected as prostate cancer. For patients with PSA < 10 µg/L, a DWI and TRUS jointly guided transrectal prostate biopsy was recommended.