Session: MP38: Prostate Cancer: Localized: Active Surveillance
MP38-08: Is a confirmatory prostate biopsy before entry into an active surveillance protocol still necessary in the era of prostate cancer diagnosis with MRI-guided biopsy?
Introduction: In patients with low-risk prostate cancer who are considering active surveillance (AS), it is common to repeat a biopsy within a year of diagnosis, as a confirmatory biopsy. The necessity of this biopsy was tested in the era before diagnosis based on MRI and showed a risk of 25-35% for reclassification in the confirmatory biopsy. Currently, most biopsies and new diagnoses of patients with a tumor suitable for AS are performed under the guidance of MRI. Our goal is to check the chance of reclassification when the diagnosis was made with an MRI-guided biopsy. Methods: A retrospective review of all confirmatory biopsies performed at our center between 2015-2021. Data were collected about the diagnostic biopsy and the confirming biopsy based on the medical sheet and the pathological report. Results: Of the 114 patients who underwent a confirmatory biopsy during the study period, 75 (65.8%) were diagnosed with a TRUS biopsy (group 1) and 39 (34.2%) with an MRI-guided biopsy (group 2). Patient age, PSA level, prostate size, PSA-D, and MRI findings were similar between groups. All confirmatory biopsies were performed with MRI guidance and included also systematic sampling. Reclassification to grade group (GG) = 2 in the confirming biopsy was found in 31/75 (41.3%) and 15/39 (38.5%) patients in groups 1 and 2, respectively. This difference is not statistically significant (p=0.77). Similar reclassification rate (3/8, 37.5%) occurred in a subgroup (of group 2) of patients with previous negative systematic biopsy. In 9/75 (12.0%) and 4/39 (10.3%) patients in groups 1 and 2, respectively, the MRI-guided samples were found without significant prostate cancer and reclassification was made only because of the systematic samples. Conclusions: The risk of reclassification in a confirmatory biopsy continues to be significant even in the era of MRI-guided diagnosis of prostate cancer. We emphasize the importance of continuing to perform confirmatory biopsies and ensuring systematic sampling alongside sampling the region of interest. SOURCE OF Funding: self funding
