Treatment of lentigo maligna with combination laser therapy: recurrence at 8 months after initial resolution

Lentigo maligna: diagnosis and treatment

Lentigo maligna (LM) is an in situ subtype of melanoma, clinically presenting as a pigmented, asymmetric macule that originates mostly on the head and neck and spreads slowly. The diagnosis may be challenging both for clinicians and pathologists. Dermatoscopy and reflectance confocal microscopy represent a useful tool in the differentiation of LM from other pigmented lesions, such as pigmented actinic keratosis, solar lentigines, seborrheic keratosis and lichen planus-like keratosis. Moreover, those non-invasive diagnostic technique may be crucial in the selection of optimal biopsy sites in equivocal lesions, in pre-surgical mapping and in evaluating and monitoring response to non-surgical treatments. Histologic examination remains the gold standard for the diagnosis of LM, showing a lentiginous proliferation of basal atypical melanocytes on a severe sun-damaged skin. The management of LM is constantly evolving. Treatments include surgery (the first choice, when available), radiotherapy and imiquimod cream (in patients not candidates to surgery). Many other possible treatments for LM have been tested, but they are not yet supported by strong evidences. We collected current guidelines and PubMed available reviews, studies and case-reports in order to make an overview on diagnosis and treatment of LM.

A systematic review of non-surgical treatments for lentigo maligna

Lentigo maligna (LM) is the most common melanocytic malignancy of the head and neck. If left untreated, LM can progress to lentigo maligna melanoma (LMM). Complete surgical excision is the gold standard for treatment, however, due to the location, size, and advanced age of patients, surgery is not always acceptable. As a result, there is ongoing interest in alternative, less invasive treatment modalities. The objective was to provide a structured review of key literature reporting the use of radiotherapy, imiquimod and laser therapy for the management of LM in patients where surgical resection is prohibited. An independent review was conducted following a comprehensive search of the National Library of Medicine using MEDLINE and PubMed, Embase, Scopus, ScienceDirect and Cochrane Library databases. Data were presented in tabular format, and crude data pooled to calculate mean recurrence rates for each therapy. 29 studies met the inclusion criteria: radiotherapy 10; topical imiquimod 10; laser therapies 9. Radiotherapy demostrated recurrence rates of up to 31% (mean 11.5%), with follow-up durations of 1-96 months. Topical imiquimod recurrence rates were up to 50% (mean 24.5%), with follow-up durations of 2-49 months. Laser therapy yielded recurrence rates of up to 100% (mean 34.4%), and follow-up durations of 8-78 months. in each of the treatment series the I(2) value measuring statistical heterogeneity exceeded the accepted threshold of 50% and as such a meta-analysis of included data were inappropriate. For non-surgical patients with LM, radiotherapy and topical imiquimod were efficacious treatments. Radiotherapy produced superior complete response rates and fewer recurrences than imiquimod although both are promising non-invasive modalities. There was no consistent body of evidence regarding laser therapy although response rates of up to 100% were reported in low quality studies. A prospective comparative trial is indicated and would provide accurate data on the long-term efficacy and overall utility of these treatments.

Melanoma in situ: Part II. Histopathology, treatment, and clinical management

Melanoma in situ (MIS) poses special challenges with regard to histopathology, treatment, and clinical management. The negligible mortality and normal life expectancy associated with patients with MIS should guide treatment for this tumor. Similarly, the approach to treatment should take into account the potential for MIS to transform into invasive melanoma, which has a significant impact on morbidity and mortality. Part II of this continuing medical education article reviews the histologic features, treatment, and management of MIS.

Lentigines, laser, and melanoma: a case series and discussion

Solar lentigines are considered one of the earliest signs of photoaging and are an extremely common cosmetic complaint. Successful removal of these lesions can be achieved with laser and non-laser light sources, and is one of the most frequently performed cosmetic procedures in laser centers. Distinguishing a benign lentigo from other pigmented lesions can sometimes be challenging, even for a trained dermatologist. We report a series of three patients who presented to our laser center within 2 months of one another for cosmetic removal of pigmented lesions that were found to be melanoma. One patient was referred by another dermatologist, one by a physician family member, and the other presented on his own. These cases highlight the need for careful evaluation of pigmented lesions prior to laser treatment, regardless of the source of the referral. In this article, we will review the diagnostic and treatment differences between lentigines and their malignant counterparts, and examine the role of laser in both.

Managing melanoma in situ

Melanoma is a highly aggressive skin cancer with an increasing incidence. Melanoma in situ is an early, non-invasive form in which the tumor is confined to the epidermis. Treatment of melanoma in situ is challenging due to the frequent subclinical microscopic spread and to the presentation on the head and neck in cosmetically sensitive areas with chronic sun damage. Optimizing tumor eradication is imperative to reduce the potential progression into invasive disease and metastasis, all while maintaining cosmesis. Multiple treatment regimens have been implemented for managing difficult melanoma in situ tumors. We provide a thorough review of surgical, and non-surgical, management of melanoma in situ which can pose therapeutic dilemmas due to size, anatomic location, and subclinical spread.

Lentigo maligna : prognosis and treatment options

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.

Management of lentigo maligna and lentigo maligna melanoma: Seminars in surgical oncology

Lentigo maligna (LM) and lentigo maligna melanoma (LMM) represent a character, histogenetic subclass of melanocytic malignancies. They often present with a prolonged phase of slow growth but once invasion has occurred, the prognostic features are identical to all other melanomas. These lesions occur primarily on the head and neck where they evolve from areas of pigmented staining to the more typical features identifiable with malignant melanomas on other skin surfaces. The treatment options and recent advances in management are reviewed.