Effect of Topical Imiquimod on Lentigo Maligna

Effect of Topical Imiquimod on Lentigo Maligna

The purpose of this study is to determine if topical imiquimod is effective in the pathological complete regression of lentigo maligna.

Inclusion Criteria:

• Clinical diagnosis of lentigo maligna (LM) (acquired pigmented macule present for more than 12 months with no change in skin surface texture or contour, no palpability, diameter >10 mm, sited on the head or neck). The lower anatomical limit is the root of the neck - a line joining the medial end of the clavicles with the medial insertion of trapezius.
• Histological findings consistent with LM (increased numbers of atypical melanocytes confined to the epidermis, sun damaged skin) in one or more 4mm punch biopsies(s) from the darkest area, reported by a pathologist with expertise in the diagnosis of melanocytic lesions, and part of a recognised NHS skin cancer Multi-Disciplinary Team.
• The upper limit of the lesion is not defined by size, but it must be suitable for complete surgical excision using a 5 mm lateral margin.
• The outline of the lesion must be easily defined visually in daylight around its entire circumference.
• Patient fit enough and willing to undergo surgery as required by the protocol.

Exclusion Criteria:

• Clinical or histological evidence of invasive melanoma including any palpability of the lesion, or clinical and/or histological evidence of regression or dermal invasion
• Aged less than 45 years
• Recurrent LM - the index lesion must not have been previously treated
• Life expectancy of less than 12 months
• Other skin lesions which may compromise the ability to complete this study, such as co-existing or adjacent melanoma or non-melanoma skin cancer. Co-existing adjacent actinic keratoses would not exclude the patient from the study
• Women of childbearing potential, who are pregnant, plan to become pregnant during their study participation or breastfeeding.
• Unable to give informed consent.
• Hypersensitivity to imiquimod or to any of the excipients (methylhydroxybenzoate (E218), propylhydroxybenzoate (E216), cetyl alcohol and stearyl alcohol).
• Taking immunosuppressive medication.
• Taking part in any other intervention study.