Lentigo Maligna

Review of Salient Characteristics and Management

Joseph R. Kallini; Supriya K. Jain; Amor Khachemoune


Am J Clin Dermatol. 2013;14(6):473-480. 

In This Article

6 Summary

Lentigo maligna is a slow-growing melanoma in situ, which may progress to lentigo maligna melanoma, one of the four subtypes of malignant melanoma. Lentigo maligna clinically presents as an asymmetric macule originating on the face, head, or neck, and slowly spreads centrifugally with increasingly irregular borders. The preferred method for diagnosing lentigo maligna is excisional biopsy. Histology shows proliferation of atypical melanocytes at the epidermal–dermal junction in small nests or single cells, coupled with underlying photodamage. The differential diagnosis for this lesion is broad: solar lentigo, seborrheic keratosis, lichen planus-like keratosis, pigmented actinic keratosis, and melanocytic nevus. Stains used in diagnosis include H&E, HMB-45, MART-1, Melan-A, Mel-5, and S-100. Wood's lamp and dermatoscopy are also helpful in diagnosis. Dermatoscopy shows asymmetrical pigmented follicular openings, linear pigmented lines forming rhomboidal structures, annular– granular structures, and perifollicular slate-gray dots and granules. Surgical excision is the preferred treatment for lentigo maligna. Techniques include Mohs micrographic surgery, geometric staged excision, and the 'spaghetti technique.' Other modalities include imiquimod, laser ablation, radiotherapy, cryotherapy, and curettage and electrodessication.