Topical imiquimod immunotherapy in the management of lentigo maligna

Abstract

Melanoma in situ of the lentigo maligna (LM) type is a precursor lesion of LM melanoma. It most commonly occurs in elderly individuals, on the head and neck. Although surgical excision is recommended, this may not be practical for large lesions at cosmetically sensitive sites. In addition, histological changes commonly extend beyond the clinical margins of the lesion. This study describes the use of imiquimod 5% cream as topical immunotherapy in the management of lentigo maligna. Twelve patients (average age 63 years, 10 female), of biopsy-proven facial LM were treated with topical imiquimod, three times a week for 6 weeks. In the absence of an inflammatory response, patients were asked to apply the treatment daily. Seven showed clearance of the LM clinically and histologically. A further three patients showed clearance histologically with persisting pigmentation due to dermal melanin and melanophages. Thus, 10 of 12 patients cleared with no relapse after a median follow-up of 6 months. Two patients failed to respond to imiquimod and their lesions were treated with surgical excision. Imiquimod was well tolerated, except in three patients who experienced an intense inflammatory response. Two of these also developed secondary infection. Imiquimod 5% cream appears to offer a potential noninvasive method for the treatment of lentigo maligna.

Viral and Nonviral Uses of Imiquimod: A Review

“…Over 80% of the subjects that completed treatment (28) have been followed for more than a year with no relapses. Powell et al 63 treated the facial LM of 12 patients with imiquimod 3 times a week for 6 weeks. Ten of the 12 patients cleared with no relapse after an average followup of 6 months.…”

“…Ten of the 12 patients cleared with no relapse after an average followup of 6 months. 63 Imiquimod efficacy is good with shorter and longer dosing regimens and is a potential alternative to surgery.…”

Treatment of Lentigo Maligna (Melanoma In Situ) With the Immune Response Modifier Imiquimod

“…Recently, several case reports have indicated that topical application of a 5% imiquimod cream may be effective in LM [2][3][4][5][6][7] and also in metastatic melanoma to skin. 8 In a pilot study that included a large number of patients with LM, 9 an initial response rate of 93% was found.…”

Management of lentigo maligna and lentigo maligna melanoma: Seminars in surgical oncology

“…Ninety-three percent of patients were histologically complete responders and 80% of these were clear of disease 1 year after treatment. A second study [87] described 12 patients with biopsyproven facial LM who were treated with topical imiquimod 5% cream three times per week for 6 weeks. Seven patients showed clinical and histological clearance of LM while three patients showed histological clearance but persistent dermal melanin pigment.…”