Prostate cancer meeting the Japanese active surveillance criteria and diagnosed by community-based prostate-specific antigen screening: A 21-year follow-up study

Objectives To evaluate the oncological outcomes of Japanese patients with prostate cancer diagnosed by community-based prostate-specific antigen screening during a 21-year period who satisfied the criteria for active surveillance. Methods Active surveillance candidates were extracted from the community-based screening registry of Otokuni district in Kyoto prefecture. The frequency of active surveillance candidates before and after publication of the active surveillance criteria in Japan was analyzed. In addition, we examined the frequency of switching to curative intervention and treatment failure among active surveillance candidates, including the patients who selected active surveillance. Results During the study period, 868 patients were diagnosed with prostate cancer and 780 of these patients were analyzed. Among them, 190 patients (24%) satisfied our active surveillance criteria (21 and 169 in the pre-active surveillance era and active surveillance era, respectively). Of the 169 patients in the active surveillance era, 74 initially selected active surveillance. The number of active surveillance candidates increased with increasing age, and the proportion of active surveillance candidates among prostate cancer patients also increased significantly each year (P < 0.001). In the active surveillance group, the median follow-up period was 4 years and 35% switched to curative intervention. Among the 190 active surveillance candidates, seven died of other causes, but there were no deaths from prostate cancer. Conclusions Changes of active surveillance candidates in one district of Japan were successfully analyzed by using consistent active surveillance selection criteria and data obtained by a single pathologist. Oncological outcomes were good among active surveillance candidates in the low-risk group.