(Objectives) Enzalutamide is an effective therapeutic options for castration resistant prostate cancer (CRPC). General fatigue is a major adverse event after commencing of enzalutamide in CRPC patients; however, its precise impact remains uncertain, especially on the duration of enzalutamide therapy. This study evaluated the relationship of general fatigue with patient age and enzalutamide treatment duration using real-world clinical data. (Patients and methods) This investigation retrospectively included patients who received enzalutamide therapy for CRPC between 2014 and 2018 at Shinshu University School of Medicine or Nagano Municipal Hospital. We classified the patients into the general fatigue group and the non-general fatigue group, and analyzed the groups in with regard to age and the duration of enzalutamide treatment. (Results) Of the 98 patients with CRPC were enrolled, 40 (40.8%) complained of general fatigue after enzalutamide induction. The median age of the study group was 78.0 years (71.0 years in the general fatigue group and 75.0 years in the non-general fatigue group), with no significant difference between the groups. Mean treatment duration was also comparable at 265.9 days in the general fatigue group and 266.5 days in the non-general fatigue group. (Conclusions) General fatigue after commencing enzalutamide was not impacted by age and did not remarkably influence the duration of therapy for CRPC.
Keywords: castration-resistant prostate cancer; enzalutamide; general fatigue.