A case of in-transit melanoma maintaining long-term remission with intensive combination therapy

Abstract

We report the case of a 53-year-old Japanese man who had undergone excision of in-transit melanomas on his lower extremities 3 years and 2 months after an initial surgery for plantar malignant melanoma but had suffered a recurrence. As the patient showed no response to the initial nivolumab therapy, we administered a dabrafenib/trametinib combination therapy, and complete remission was achieved after 3 months. However, the in-transit melanomas recurred after the treatment had been discontinued. Nivolumab therapy was therefore restarted in combination with radiotherapy, and thereafter local injection of interferon-β was performed, resulting in the disappearance of the in-transit melanomas. The present case suggests that a combination therapy with immune checkpoint inhibitors and local treatments such as radiation and interferon-β may exert various antitumor effects, thus improving the prognosis and local control of the melanoma.[Skin Cancer (Japan) 2021 ; 36 : 38-43]