Deaths within 12 months after ¹²⁵I implantation for brachytherapy of prostate cancer: An investigation of radiation safety issues in Japan (2003-2010)

Purpose: The International Commission on Radiological Protection recommends removing the prostate before cremation if death occurs within 12 months after ¹²⁵I brachytherapy. However, the incidence of death within this time frame has not been robustly investigated in any country. The purpose this study was to investigate the incidence and cause of death and actions taken when death has occurred within 12 months after ¹²⁵I brachytherapy for prostate cancer in Japan. Methods and Materials: Data were extracted from the Japan Radioisotope Association database to investigate the total number of implantation cases, number of early deaths after implantation, cause of death, and postmortem actions between September 2003 and the end of June 2010 in Japan. Early death was defined as occurring within 12 months after ¹²⁵I brachytherapy for prostate cancer. Results: During the study period, 15,427 patients underwent ¹²⁵I brachytherapy and 43 (0.28%) died within 12 months after implantation. For 37 of the 43 patients (86%), the brachytherapy source was retrieved together with the prostate gland at autopsy; however, autopsy could not be performed in six (14%) of the deceased patients. The largest proportion of early deaths was because of cerebrovascular or cardiovascular disease (17/43, 40%), followed by malignant tumor (15/43, 35%), and respiratory disease or infection (7/43, 16%). Conclusions: The incidence of early deaths within 12 months after ¹²⁵I brachytherapy in Japan was 0.28%. In almost all cases, the brachytherapy sources were removed in the intact prostate before the body was cremated and stored appropriately.