Histopathological results after MRТ/US fusion guided biopsy of prostate lesions classified asPIRADS 3

Abstract

Introduction: Мagnetic resonance tomography (MRT) has become an established part of prostate cancer diagnosis. MRT/US fusion guided biopsy enables obtaining tissue samples directly from lesions suspected for prostate cancer. The introduction of the Prostate Imaging-Reporting and Data System (PI-RADS) precises the cases in which performance of target biopsy is needed by categorization of suspected prostate lesions according to the probability of detecting prostate cancer. It is debatable whether PI-RADS 3 lesions in MRТ (MRТ) represent a significant risk for prostate cancer. Objectivе: The objective of this study is to assess the incidence of carcinoma-positive histological results in PIRADS 3 compliant lesions from MRТ. Material and methods: Medical records of 99 patients, who underwent transperineal MRТ/US fusion prostate biopsy of suspicious lesions on MRТ, classified as PI-RADS 3, between January 2019 and December 2022 were retrospectively analyzed. Results: Patients` mean age was 65.6±6.8 years. Mean volume of the prostate gland was 54.2±20.2 cc and the mean value of prostate-specific antigen was 18.5±6.3. Pathologic finding from digital rectal examination of the prostate gland appeared in 18 (18.2%) patients. Mean size of the lesion from MRI was 12.9±5.24 mm. The suspect lesions were localized mainly in the peripheral zone of the prostate gland – 60 (60.6%), secondly in the transitional zone – 35 (35.4%). Seminal vesicles invasion and lymphade-nomegaly were rare – 1 (1%) and 2 (2%) cases. Histopathological results in 63 (63.6%) patients was benign prostatic hyperplasia. 24 (24.2%) lesions were classified as 3+3=6 according to Gleason Score, 4 (4.0%) as 3+4=7 and 8 (8.1%) as 4+3=7. Conclusion: The results of this retrospective study shows that PI-RADS 3 lesions take an intermediate position in regard to histopathological findings. The resulting almost equal number of patients diagnosed with BPH and prostate cancer is proof of this. PI-RADS 3 lesions carry a relatively small risk of clinically significant cancer (csPCa).