Métastases en transit du mélanome : efficacité de l’imiquimod topique combiné au laser CO2 ou à l’électrocoagulation

The role of topical imiquimod in melanoma cutaneous metastases: A critical review of the literature

Despite of the emerging new systemic and local oncologic treatments (immunotherapy and checkpoint inhibitors, oncolytic viral treatments and injected immunostimulants) the management of skin melanoma metastasis can be still challenging. The main aim of this review was to assess the efficacy and the role of imiquimod in local metastatic melanoma disease. An extensive literature review was performed from September 2000 to March 2020 using PubMed, MEDLINE, Embase, and Cochrane Library databases. Selected articles regarded topical imiquimod, its mode of action as an antitumoral agent and its applications in melanoma metastases treatment. We analyzed a total of 18 published article of clinical cases and small case series and five studies: two retrospective large case series, two Phase I and II clinical trials and one cohort non randomized study. Generally, the treatment is safe and well tolerated. Imiquimod lead to an unstable locoregional control. The use of topical imiquimod for the treatment of MM cutaneous metastases should be considered in selected cases and in palliative settings.

Anti-Melanoma immunity and local regression of cutaneous metastases in melanoma patients treated with monobenzone and imiquimod; a phase 2 a trial

Vitiligo development in melanoma patients during immunotherapy is a favorable prognostic sign and indicates breakage of tolerance against melanocytic/melanoma antigens. We investigated a novel immunotherapeutic approach of the skin-depigmenting compound monobenzone synergizing with imiquimod in inducing antimelanoma immunity and melanoma regression. Stage III-IV melanoma patients with non-resectable cutaneous melanoma metastases were treated with monobenzone and imiquimod (MI) therapy applied locally to cutaneous metastases and adjacent skin during 12 weeks, or longer. Twenty-one of 25 enrolled patients were evaluable for clinical assessment at 12 weeks. MI therapy was well-tolerated. Partial regression of cutaneous metastases was observed in 8 patients and stable disease in 1 patient, reaching the statistical endpoint of treatment efficacy. Continued treatment induced clinical response in 11 patients, including complete responses in three patients. Seven patients developed vitiligo-like depigmentation on areas of skin that were not treated with MI therapy, indicating a systemic effect of MI therapy. Melanoma-specific antibody responses were induced in 7 of 17 patients tested and melanoma-specific CD8+T-cell responses in 11 of 15 patients tested. These systemic immune responses were significantly increased during therapy as compared to baseline in responding patients. This study shows that MI therapy induces local and systemic anti-melanoma immunity and local regression of cutaneous metastases in 38% of patients, or 52% during prolonged therapy. This study provides proof-of-concept of MI therapy, a low-cost, broadly applicable and well-tolerated treatment for cutaneous melanoma metastases, attractive for further clinical investigation.