Complete remission of metastatic carcinoma of the prostate with bicalutamide withdrawal

An 83-year-old man was diagnosed with stage 4 prostate cancer with a Gleason score of 7 (3+4). His initial prostate-specific antigen (PSA) level was 965 ng/dL, and he demonstrated extensive metastatic disease of the thoracic spine. After an initial response to monthly leuprolide injections, his PSA level began to increase and bicalutamide was added. An initial decrease in his PSA level was observed; however, the level gradually rose to 212 ng/dL and bicalutamide was discontinued. Three months later, his PSA level was <0.05 ng/dL and has remained <1 ng/dL for the past 27 months. Bicalutamide withdrawal usually leads to transient remission, with PSA level dropping to approximately 50% of the initial level. The duration of the remission is usually limited to approximately 6 months. However, the sustained response that was observed in our patient suggests that a trial of androgen withdrawal, even in the setting of rising PSA levels, might be reasonable before initiating more toxic therapies.