Symptomatic Response of Apalutamide in Local Treatment Ineligible Non - Metastatic Castration - Resistant Prostate Carcinoma Patients: Thailand's First Report

Abstract

          Non - metastatic castration - resistant prostate cancer (nmCRPC) may cause local symptoms due to the invasion of the surrounding organs, e.g., pain and hematuria. Apalutamide is one of the current standard treatments owing to the data confirming the increased survival rate and metastatic free survival (MFS). However, no overall response rate of this drug has been reported in Phase 3 clinical trials. Therefore, there were no sufficient data for the clinical justification of this drug on the reduction of the symptoms related to the local invasion of the tumor. 

          This case report is a study of an 82 - year - old Thai male with nmCRPC presenting the symptoms of pain, hematuria, and difficulty walking because of the invasion of the bladder and pelvic floor muscles. Radiotherapy could not be applied due to concerns regarding its side effects. The patient was afterward treated with apalutamide. After four months, the tumor was reduced by 42% resulting in the disappearance of the local symptoms. This was the first case report regarding the efficacy of apalutamide in the reduction of the size of nmCRPC in patients with local symptoms.