Adverse Event Reports and Safety Measures for Breast Implant–associated Anaplastic Large Cell Lymphoma in Japan

Background: A causal association between breast implant–associated anaplastic large cell lymphoma (BIA-ALCL) and macrotextured breast implants has been established. In response, global surveillance of implant-based breast reconstruction safety has intensified. We investigated the frequency of BIA-ALCL in patients receiving gel-filled breast implants and tissue expanders approved in Japan. Methods: We reviewed adverse event reports submitted to the Pharmaceuticals and Medical Devices Agency between April 1, 2013, and March 31, 2024, and examined safety measures implemented by marketing authorization holders and the Ministry of Health, Labour and Welfare. Results: A total of 736 adverse events were reported in patients with gel-filled breast implants, whereas 296 were reported in those with tissue expanders. Following the global recall of Allergan’s Biocell products, adverse event reports rose markedly between FY2019 and FY2022. In Japan, 2 confirmed cases of BIA-ALCL were reported in FY2021 and FY2023, and 8 suspected cases were reported between FY2020 and FY2023. Allergan voluntarily recalled its Biocell products due to their risk of BIA-ALCL and issued a field safety notice with risk information and recommendations. The Ministry of Health, Labour and Welfare issued public notices referencing academic society guidelines and updated the package insert precautions for gel-filled breast implants. Conclusions: Fewer BIA-ALCL cases have been reported in Japan than in the United States and Europe, likely due to early, coordinated safety measures.