Health-related quality of life in Japanese low-risk prostate cancer patients choosing active surveillance: 3-year follow-up from PRIAS-JAPAN.

ABSTRACT

PURPOSE: To evaluate the health-related quality of life (HRQoL) of Japanese men on active surveillance (AS) in the Prostate cancer Research International Active Surveillance study in Japan (PRIAS-JAPAN). METHODS: Participants were included in the PRIAS-JAPAN HRQoL study between January 2010 and March 2016. Their general HRQoL was assessed using a validated Japanese version of the Short-Form 8 Health Survey (SF-8) at enrolment and annually thereafter until discontinuation of AS. The SF-8 mental component summary (MCS) and physical component summary (PCS) of men on AS were compared with scores of the general population (norm-based score [NBS] 50) and MCS and PCS scores for men following AS were analysed over time. We tested whether MCS and PCS scores over time explained discontinuation of AS. RESULTS: Five hundred and twenty-five patients enrolled, and the median age at baseline was 68 years. At enrolment and after 1-, 2-, and 3-year follow-ups, the PCS and MCS scores were significantly higher than the NBS of the general Japanese population except for the median PCS at 3 years. We found that age at diagnosis and time on AS negatively affected the PCS score of men on AS, while every additional year on AS led to a 0.27 point increase in MCS scores. Neither PCS nor MCS were predictors for discontinuation of AS. CONCLUSION: Japanese men following an AS strategy for 3 years reported better HRQoL compared with the general population, indicating that monitoring Japanese low-risk prostate cancer patients can be an effective treatment strategy. STUDY REGISTRATION Clinical trial registry-UMIN (University Hospital Medical Information Network); UMIN000002874 (2009/12/11).