Characteristics of prostate biopsy in patients under the dutasteride treatment

We performed a retrospective study to clarify the characteristics of prostate biopsies in patients treated with dutasteride, a benign prostate hyperplasia treatment drug that inhibits 5α-reductase. We studied the digital clinical data of 677 patients, including 96 cases treated with dutasteride, with suspected localized prostate cancer. All patients underwent transrectal ultrasonography-guided prostate biopsy between 2014 and 2017 in our department. A propensity score matching analysis was performed based on prostate-specific antigen (PSA) (calculated as double the PSA value for the dutasteride group) and age. Ninety-six patients in each of the dutasteride and control groups were assessed and their characteristics were compared. The characteristics of the patients in the dutasteride and control groups were well balanced by matching. There were fewer prostate cancer-positive patients in the dutasteride group. When comparing only the prostate cancer-positive patients in each group, there were significantly more cases of high-grade cancers and abnormal magnetic resonance imaging (MRI) findings in the dutasteride group. In the dutasteride group, abnormal MRI findings and advanced age were significant predictors of high grade cancer. This study shows the characteristics of prostate biopsies in patients treated with dutasteride and indicates that patients on dutasteride with advanced age and abnormal MRI findings should undergo prostate biopsy.