Apalutamide-induced severe interstitial lung disease: A report of two cases from Japan.

Apalutamide, a competitive inhibitor of the androgen receptor, is being increasingly used for the treatment of prostate cancer. There have been few reports of interstitial lung disease in clinical trials of apalutamide. However, two cases of apalutamide-induced interstitial lung disease with respiratory failure in Japanese males, who were successfully treated with high-dose corticosteroids, are presented here. These cases suggest that clinicians should be alert to the potentially life-threatening risk of pulmonary toxicity associated with apalutamide treatment.