The experience of immune checkpoint inhibitors in Chinese patients with metastatic melanoma: a retrospective case series.

Melanomas in Chinese patients show relatively higher rates of acral and mucosal types than in other populations. However, the efficacy of checkpoint inhibitor therapies against these melanoma subtypes is not well defined. We analyzed 52 patients treated with ipilimumab, pembrolizumab, or a combination of both to evaluate the efficacy and safety of checkpoint inhibitors in Chinese patients with advanced melanoma, particularly those with acral and mucosal types. The objective response rates (ORRs) were 0, 25, and 20% for ipilimumab, pembrolizumab, and pembrolizumab plus ipilimumab, respectively. Pembrolizumab contained therapy was as effective in acral and mucosal melanoma patients (ORR 26.7 and 20%, respectively) as in non-acral cutaneous melanoma patients (ORR 26.7%). Baseline lactate dehydrogenase levels and relative lymphocyte counts were independent prognostic factors for PFS and OS. The incidences of grade 3-4 adverse events were 14% in the two monotherapy groups and 30% in the combined therapy group. The most frequent adverse events were elevation of aminotransferase, skin toxicity, thyroid dysfunction, pyrexia, and fatigue. Treatment-related rash or vitiligo was associated with a better prognosis. In summary, pembrolizumab-based therapy resulted in meaningful efficacy and good tolerability in Chinese patients with melanoma, including those with acral and mucosal types.