Objectives: To date, it is unknown whether systematic biopsies can be safely omitted in patients with unsuspicious MRI findings or if systematic biopsies should be required when targeting focal lesions (PI-RADS 3-5).
Methods: A series of 366 patients (249 without a previous biopsy) were examined in a 1.5 Tesla MRI scanner. All patients were submitted to systematic biopsies (12-14 regions) with additional targeted biopsies (by cognitive fusion) of focal PI-RADS lesions (PI-RADS 3-5).
Results: In our series, patients with PI-RADS 1/2 findings had rates of adenocarcinoma of any grade, >GG1 and GG4/5 of 34%, 14% and 3%, respectively. The use of MRI prior to biopsy in our series increased the detection of clinically significant prostate cancer (CSPCa) in 28% of patients with focal lesions, and focal lesions were present in 293/366 (80%) of all patients. For CSPCa (>GG1), targeted biopsies improved the diagnosis in 28% of patients, while systematic biopsies resulted in an additional 19% of cancer cases in the series.
Conclusion: Systematic biopsies should still be considered in patients with PI-RADS 1/2 findings. Our findings also suggest a stronger benefit of the combined strategy of targeted and systematic biopsies than the findings of previous studies concerning the detection of CSPCa in biopsy-naïve patients.
Keywords: Magnetic resonance imaging; biopsy; diagnosis; needle; prostatic neoplasms.