Lentigo Maligna

Abstract

Lentigo maligna is a premalignant melanocytic neoplasm occurring on the sun-exposed skin of the middle-aged and elderly. It is believed to represent the in situ phase of lentigo maligna melanoma and, as such, cure is usually the aim of treatment. However, factors such as site and size of lesion and patient co-morbidities may influence the treatment modality undertaken. Surgical excision is the treatment of choice to obtain clinical and histologic clearance, but many other modalities have been used with variable success. Mohs micrographic surgery is associated with the lowest recurrence rate at 4-5%, but conventional surgery, cryotherapy and radiotherapy also yield good results, with recurrence rates in the order of 7-10%. Other treatments have been tried but currently there are not enough data to support their routine use. In order to make the best decision regarding appropriate management of lentigo maligna, the dermatologist or surgeon must be aware of all the options available and the evidence supporting their use.

The Invasive Growth Potential of Residual Melanoma and Melanoma In Situ

“…Surgical excision of primary invasive melanoma is the recognized standard of care for melanomas of all depths 11–14 . The recommended margins for standard excision are well recognized but remain a source of some controversy 15–19 . Even with these margins, the recurrence rate is 3% on the trunk and proximal extremities 7 .…”

Mohs Surgery for the Treatment of Melanoma in Situ: A Review

“…Among dermatologists, there is substantial variability in the management of melanoma in situ (MIS). Despite several recently published reviews of treatment options for MIS, 1–4 current data suggest that there is little consensus among dermatologists regarding the appropriate surgical margins or depth of excision for MIS 5 . In addition, many dermatologists are uncertain about the rate of progression of MIS lesions to metastatic disease if left untreated 5 …”

Lentigo Maligna—Outcomes of Treatment with Q-Switched Nd:YAG and Alexandrite Lasers

“…Despite high recurrence rates, surgical excision remains the criterion standard treatment for lentigo maligne (LM), 1 but as the majority of the affected patients are elderly and may have multiple comorbidities, it may not always be a suitable therapeutic option. Moreover, despite the premalignant potential of LM, younger patients may decline surgical excision, because 90% of LMs occur on the head and neck, and surgical excision may be cosmetically challenging.…”

“…Use of precise histological margin control with Mohs micrographic surgery may result in excision of large areas of skin, with uncertain benefit. Alternative therapeutic options that have been used with variable success include cryotherapy, radiation, and laser therapy 1 . Cryotherapy and radiation produce nonselective tissue destruction, so the theoretical risk of recurrence and extent of tissue destruction is higher.…”