Abstract
The prognosis of malignant melanoma is one of the poorest among all cancers, and there has been little progress in drug treatment, resulting in a markedly poor prognosis for advanced cases. However, since 2010, many new drugs have been developed and clinically applied, and new findings have been reported. The most recent change in Japanese pharmacotherapy for malignant melanoma was the coverage of immune checkpoint inhibitors (ICIs) by insurance in 2014 prior to their use for other cancers. The anti–PD-1 antibody drug nivolumab was approved in 2014, the anti-CTLA-4 antibody drug ipilimumab was approved in 2015, and the humanized anti-human PD-1 monoclonal antibody drug pembrolizumab was approved in 2016. We also use ICIs for patients with unresectable malignant melanoma. At our hospital, ten patients were treated using ICIs between December 2014 and November 2018. On evaluation of the treatment effects, only one patient had stable disease, whereas the others had progressive disease. Eight patients died after deciding to receive best supportive care. Immune-related adverse events (irAE) varied, but they were resolved after the interruption of ICIs and systemic administration of steroids. Although this study only included patients from our department, the effects of ICIs were limited and insufficient considering their cost effectiveness and irAE. Regarding the future use of ICIs, they should be administered to specific patients following a designated time course. In order to select patients, effective biomarkers that can predict the efficacy of treatment and the degree of irAE need to be developed.
