Vitiligo: a good prognostic factor in melanoma?

The association of vitiligo with immunologic therapy for melanoma is generally regarded as a good prognostic factor. Nevertheless, the immunopathogenesis of vitiligo remains incompletely understood. The authors report the case of a 71-year-old Caucasian woman who had a malignant melanoma on the posterior aspect of the left leg in 1982. The patient underwent wide local excision and elective left inguinal lymphadenectomy. Sixteen years later two amelanotic malignant melanoma metastases were observed on the left inferior limb and were excised. Interferon treatment was administered for only eight months owing to side effect intolerance. Two years later, vitiligo-like macules appeared over her face and trunk. Since then, several further cutaneous metastases were found; all of them were limited to the left inferior limb. The patient remained free of visceral metastasis until December 2007, when a single lung mass was identified on a CT scan. The distinctive feature in this patient was a long survival that was free of identifiable visceral metastases. Despite the two year gap between the appearance of vitiligo and interferon treatment, the former might be indicative of a delayed immunological response against the melanoma cells, supporting the concept of a better therapeutic outcome in this cluster of patients.