Melanoma in Situ Treated with Topical Imiquimod for Management of Persistently Positive Margins: A Review of Treatment Methods.

Background: Imiquimod is a topical cream approved by the US Food and Drug Administration for treatment of superficial basal cell carcinoma, actinic keratosis, and genital-perianal warts. Its successful use in patients with persistently positive margins of melanoma in situ (MIS) after surgical excision has been previously reported.

Case report: A 75-year-old female presented with a primary melanoma that was removed through an elliptical excision with 1 cm margins. Pathology revealed 3 involved margins with residual MIS without an invasive component. After a second operation removed an additional 1 cm margin, pathology revealed 2 positive margins with residual MIS. Rather than undergoing a third excision, the patient decided to pursue a nonsurgical approach with topical imiquimod, and at the 4-month follow-up examination, the incision was completely healed with no clinical evidence of tumor recurrence.

Conclusion: A nonsurgical approach with 5% topical imiquimod cream applied along the incision was utilized. In specific patient populations, the use of imiquimod is a reasonable alternative approach for the management of persistently positive MIS margins. Long-term follow-up is necessary to assess for evidence of recurrence and the ultimate success of this nonsurgical approach.