Vitiligo and melanoma-associated hypopigmentation (MAH): shared and discriminative features

Background: It is unclear if differences between melanoma-associated hypopigmentation (MAH) and classical vitiligo exist. Patients and Methods: Hypopigmented areas and associated lesions (halo nevi, hypopigmented scars) in 15 melanoma patients and 31 patients with classical vitiligo were analyzed by digital photography. The activity of the respective lesions was assessed by the vitiligo disease activity (VIDA) score. Associated diseases were recorded by history and serological tests; genotyping of HLA class I antigens as well as histology/immunohistology were performed. Results: MAH were diagnosed in 12 of 15 melanoma patients; mean onset was 4.8 years after the primary diagnosis of the melanoma. Three melanoma patients reported hypopigmentation more than 15 years before diagnosis of melanoma. In the history and family history of vitiligo patients, autoimmune diseases were much more frequent and haplotype HLA-A2 was twice as common compared to MAH patients. MAH lesions were most often distributed in a bilateral symmetrical pattern, corresponding to vitiligo. MAN was less progressive compared to classical vitiligo; however, it was more often associated with other acquired leukodermas. In both groups hypopigmentation spread centripetally to the trunk. Histological and immunohistological differences were not found. Conclusions: Whereas differences exist concerning associated autoimmune diseases, MAH and vitiligo shared many common clinical and histological features. Further studies are needed to assess the clinical relevance of vitiligo-like alterations in melanoma patients.