Prostate cancer adverse pathology reclassification in patients undergoing active surveillance in a long-term follow-up series

Background Active surveillance (AS) has become a valid option for patients with a very low risk of prostate cancer (PC) with a widespread application. There are still a few series, with a medium follow-up longer than 5 years, reporting data on pathological upgrading. The objective is to evaluate the changes in surveillance biopsies of patients with low-risk PC in a long-term follow-up and determine if a longer stay in AS could involve worse pathological findings. Materials and Methods A retrospective analysis of our institutional database of patients with PC undergoing AS during 2004 to 2018 was performed. The inclusion criteria were prostate-specific antigen (PSA) <= 10 ng/mL, Gleason grade 1 and T1c/T2a. Patients were assessed by serum PSA level and digital rectal examination at 6-month intervals. Transrectal ultrasound-guided prostate biopsies were performed during the first year of follow-up, and every 2 or 3 years thereafter. The pathology details of biopsies were analyzed and compared with the current series on AS. Results Three-hundred nineteen patients undergoing AS were evaluated with a median follow-up of 5.3 years and a mean age of 67.4 years. Sixty-three patients did not meet all the criteria to be considered low-risk PC but were included in the analysis. Overall, 128 patients (40.1%) underwent active treatment (84.7% of them due to pathological progression in surveillance biopsies). The proportion of patients with a reported upgrading ranged between 19.4% and 35.3%, although only the fourth biopsy showed an upgrading proportion of over 30%. Limitations include the retrospective design of the study and the existence of different protocols between other cohorts that make it difficult to compare their results. Conclusions For patients who remained in surveillance the percentage of upgrading increased slightly with the time, being more frequent after the third-surveillance biopsy. These findings support the importance of extending surveillance biopsies for patients who remain candidates for curative treatment.