Topical azelaic acid therapy for palpebral lesions of melanoma in situ (lentigo maligna) and for melanoma in situ progressed to invasive melanoma. A report on four cases

Azelaic acid has been shown to have a biological antiproliferative and cytotoxic effect on the abnormally hyperactive and malignant melanocyte both in vivo and in vitro. Here, beneficial effects of topical azelaic therapy on four facial lesions where surgery was not considered to be a primary or available option are described. Two were cases of melanoma in situ involving the lower eyelid. In one, complete regression of the lesion was achieved and maintained for six years. In the other, the overall lesional area was greatly reduced, allowing discrete excision of small relapses with no recurrences for up to nine years: this case demonstrates an adjuvant effect of azelaic acid therapy on surgery, in reducing the overall area to be excised. The other two cases were of melanoma in situ progressed to invasive malignant melanoma in which complete clinical regression of the lesions was achieved, in one case for up to five years. Treatment in these cases was essentially palliative, with probable prolongation of life in one, and certainly, improvement in quality of remaining life in both. Newer formulations for topical application, possibly combined with oral or even systemic administration, could lead to increased delivery of azelaic acid to lesional sites and reduction in treatment time with similar cases in future.