Androgen deprivation therapy duration is significantly associated with Testosterone recovery in Japanese patients with prostate cancer

Objective Due to the fear generated by COVID‐19 in Spring 2020, many patients postponed their scheduled outpatient visits. To differentiate those patients with prostate cancer (PCa) whose androgen deprivation therapy (ADT) injection treatment can be postponed, we investigated the characteristics of testosterone (T) recovery in Japanese patients after they received combined ADT and radiation therapy (RT). Methods We included 81 patients with PCa treated with ADT and RT at Keio University Hospital from January 2013 to December 2018. T‐recovery was defined as the time interval between the last ADT injection and 3–6 months after T‐normalization. The Kaplan–Meier method was used to estimate time to T‐recovery. Cox proportional hazards models identified T‐recovery predictors. Results The 50% cumulative incidence of T‐recovery was 7.0 months for the 6‐short‐term group (defined as patients having ≤6 months of ADT therapy) versus 13.0 months for the 6‐long‐term group (>6 months of therapy) (p