Correlation Between Toripalimab Immune Therapy and Vitiligo: A Case Report of Complete Response and Adverse Reactions in Advanced Stage Melanoma of Unknown Primary

Melanoma of unknown primary (MUP) is a rare subtype of melanoma, accounting for approximately 3% of cases and characterised by metastasis in the absence of a detectable primary lesion.This report describes the case of a stage IV MUP patient with a BRAF V600E mutation who developed vitiligo, an immune-related adverse event, following treatment with toripalimab, an immune checkpoint inhibitor (ICI).Despite experiencing vitiligo-a common skin toxicity associated with ICI therapy-the patient achieved complete remission.This case highlights the potential for ICIs to induce unexpected skin reactions and underscores the importance of monitoring and managing such events in MUP patients undergoing treatment with toripalimab.