Trends in the prognosis of metastatic melanoma in the era of targeted therapy and immunotherapy: A single-institution survey in Japan.

Abstract

Advances in anticancer therapy, including the development of targeted therapy and immunotherapy, have drastically changed treatment options for metastatic melanoma. However, to date, only a few studies have been published that directly compare overall survival (OS) before and after introduction of these new therapeutic options in Japan. We retrospectively surveyed patients with metastatic melanoma treated in our hospital between 1989 and 2019 to investigate the OS benefit of the new therapies. A total of 115 patients with metastatic melanoma (cutaneous origin, 92; mucosal, 14; uveal, two) were included in the study. Kaplan-Meier analysis showed that the patient group receiving targeted therapy/immunotherapy (TT/IT) (n=47) had a median OS of 19.0months, which was longer than that in patients receiving conventional chemotherapy (n=42, 8.0months) or no treatment (n=26, 6.0months) (P<0.001). In the subgroup analysis performed for the TT/IT group, patients of younger age and with the BRAF mutation had significantly improved OS. As the number of treatment lines increased, the median OS tended to become longer. Our real-world data confirmed an improvement of median OS upon the introduction of the new therapies for metastatic melanoma. However, the long-term OS benefit was limited, possibly because of racial differences in some of the clinical characteristics. To improve the overall melanoma prognosis, the entire treatment strategy, including perioperative therapy needs strengthening.