Role of debulking surgery in combination with immune therapy: A successfully treated case of locally advanced mucosal melanoma.

Immune checkpoint inhibitors (ICIs) have markedly changed the treatment landscape for melanoma; however, their efficacy and applications are currently limited and medical requirements remain unmet. The present case study reports on a 85-year-old female patient who visited our outpatient clinic with a 1-month history of a buccal mucosa mass and was diagnosed with locally advanced mucosal melanoma of the head and neck. The patient's tumor progressed right after the administration of nivolumab, compromising oral intake. Palliative debulking surgery was performed. Subsequently, the other part of the melanoma on the hard palate slightly decreased in size without forming new lesions for more than one year after surgery. The present case exemplifies that tumor volume reduction surgery may increase the response to ICI and may prolong the duration of response. This combination therapy may be more effective in patients whose tumors increase in size after administration of ICIs or whose tumor is already large at the beginning of treatment. The combination of ICIs and debulking surgery may become an important treatment option in the future for locally advanced mucosal melanoma.