Background: Chronic prostatitis (CP) can impair health-related quality of life (QOL), but the full impact of CP, including the impact of CP-like symptoms in men who have no CP diagnosis (CPS), is unknown. We estimated the impact of diagnosed CP (DCP) and CPS on Health-related QOL. Methods: From a representative nationwide survey of men aged 20–84 in Japan, we determined the prevalence of DCP and also of CPS. For CPS, we used Nickel’s criteria, which were used previously to estimate the prevalence of CP and are based on the NIH Chronic Prostatitis Symptom Index. To test the robustness of Nickel’s criteria, we used two other definitions of CPS (two sensitivity analyses). We measured QOL with the Short-Form 12-Item Health Survey. We compared the participants’ QOL scores with the national-norm scores, and with the scores of men who had benign prostatic hyperplasia (BPH). Results: Among the 5 010 participants, 1.4% had DCP and 3.7% had CPS. The sensitivity analyses resulted in CPS prevalence estimates of 3.1% and 4.5%. CPS was particularly common in younger participants (5.7% of those in their 30 s had CPS). QOL was very low among men with CP: In most areas (domains) of QOL, their scores were more than 0.5 standard deviation below the national-norm mean. Their mental-health scores were lower than those of men with BPH. The lowest scores among all 8 QOL domains were in role-functioning. Conclusions: CP is common, but it is underdiagnosed, particularly in younger men. Whether diagnosed or only suspected, CP’s impact on QOL is large. Because CP is common, and because it substantially impairs individuals’ QOL and can also reduce societal productivity, it requires more attention. Specifically, needed now is a simple tool for urologists and for primary care providers, to identify men, particularly young men, whose QOL is impaired by CP.

Introduction: Apalutamide‐associated skin rash is a more common adverse event in the Japanese population than in the global population. However, its mechanism remains elusive, and limited histopathological information hampers further understanding.Case presentation: Case 1: a 71‐year‐old man with metastatic castration‐sensitive prostate cancer developed a skin rash after 70 days of apalutamide treatment. Case 2: a 71‐year‐old man with non‐metastatic castration‐resistant prostate cancer developed a skin rash after 71 days of apalutamide treatment. In both cases, the skin rash presented as a slightly exudative erythema. The histology showed spongiosis of the epidermis and perivascular and interstitial infiltration of lymphocytes and eosinophils in the upper dermis without necrotic keratinocytes.Conclusion: Apalutamide‐induced skin rashes can involve an eczematous reaction clinically and histologically.

Introduction: Acute generalized exanthematous pustulosis is a type of severe cutaneous drug adverse reaction. While apalutamide is known for its high incidence of cutaneous adverse events, it remains unknown whether acute generalized exanthematous pustulosis can develop during apalutamide treatment.Case presentation: A 72‐year‐old man with metastatic castration‐sensitive prostate cancer developed small erythema on the face and trunk after 41 days of apalutamide treatment. Three days later, apalutamide was discontinued. However, 9 days after the discontinuation of apalutamide, the patient had a high fever with hemodynamic instability and showed diffuse erythema throughout the body with numerous small pustules. Skin biopsy revealed subcorneal and intraepidermal pustules admixed with many eosinophils, which led to the diagnosis of acute generalized exanthematous pustulosis. The skin rash improved in 14 days with systemic corticosteroid administration.Conclusion: We present the first case of a skin rash with clinical features of acute generalized exanthematous pustulosis during apalutamide treatment.