[A CASE OF SEVERE DRUG INDUCED ERUPTION AFTER APALUTAMIDE USE FOR METASTATIC HORMONE-SENSITIVE PROSTATE CANCER, WHICH WAS DETERIORATED FROM TEMPORARY REMISSION AFTER DRUG WITHDRAWAL].

A 70-years-old man with metastatic hormone-sensitive prostate cancer received the apalutamide, an oral androgen receptor signaling inhibitor. On day10 after drug initiation, fever and skin rash appeared on his whole-body surface. He stopped taking the drug on day18 and skin symptoms temporarily improved about 7 days after discontinuation. However, on day 38, symptoms recurred, and the patient was admitted to the hospital as an emergency due to suspicion of Stevens-Johnson syndrome. Steroid pulse therapy was administered, and gradual improvement of the skin lesions was observed. With the widespread use of apalutamide in daily clinical settings, severe drug eruptions such as the present case may potentially increase, and further additive experiences are awaited.