Nonsurgical Treatment of Lentigo Maligna with Imiquimod and Cryotherapy: A Case Report

Lentigo maligna (LM) is a melanoma in situ caused by prolonged ultraviolet radiation exposure, most commonly affecting the head and neck of older adults. Although often indolent, LM progresses to invasive lentigo maligna melanoma in approximately 5% of cases. Surgical excision remains the gold standard, but alternatives are required for patients who are poor surgical candidates.

A 92-year-old female with a history of nonmelanoma skin cancer presented with a 7.0 × 7.0 cm pigmented lesion on the left zygomatic region. Dermoscopy revealed features consistent with LM, and biopsy confirmed an early evolving lesion. Given her age and preference to avoid surgery, topical imiquimod 5% cream was prescribed. Treatment consisted of once-daily application, 5 days per week, for 16 weeks. Residual pigmentation was subsequently treated with cryotherapy. After 16 weeks of imiquimod therapy, the lesion showed significant regression in size and pigmentation. Cryotherapy further reduced residual areas, and at 6-month follow-up, complete clinical and histopathologic resolution was observed. The patient tolerated treatment well, with no significant adverse effects.

This case highlights the efficacy of imiquimod in combination with cryotherapy as a nonsurgical treatment option for LM, particularly in elderly patients or those unfit for surgery. Our approach offers a safe, viable alternative to excision, with minimal side effects, while underscoring the need for vigilant follow-up to monitor for recurrence.