Recurrent in situ melanoma successfully treated with ingenol mebutate.

Background: Treatment options for melanoma in situ (MIS) include imiquimod, radiation therapy, cryotherapy, excisional and Mohs surgery. Ingenol mebutate is a new topical treatment option recognized for actinic keratosis. Although in vitro effectiveness has been demonstrated on melanoma cell lines, its therapeutic potential for in vivo melanomas is unknown.

Case Report: In 2011, a 91-year-old woman presented a thick melanoma of her cheek. The lateral sections revealed persisting in situ melanoma, which were again excised. She presented for follow-up and a recurrent MIS was evidenced centered on the previous scar. She refused further surgery and ingenol mebutate (0.015% gel) was administered on three consecutive days. One month later, a complete clinical resolution was observed. Histology and immunohistology revealed no residual MIS.

Conclusion: In this patient, ingenol mebutate was successful and well-tolerated as a topical, alternative therapy for MIS after failure of other treatment options.