Following lentigo maligna may not prevent the development of life-threatening melanoma.

BACKGROUND--Management of lentigo maligna (Hutchinson's melanotic freckle, in situ lentigo maligna melanoma) by regular observation relies on the detection of invasive melanoma before it has developed significant life-threatening potential. Recent studies indicate that lentigo maligna melanoma does not have a better prognosis than other forms of melanoma. OBSERVATIONS--A case is reported of an amelanotic lentigo maligna that evolved from a macular lesion to a deeply invasive, amelanotic, lentigo maligna melanoma within 6 months. The melanoma was Clark level IV and measured 3.0 mm in maximum tumor thickness. CONCLUSIONS--Observation of lentigo maligna at 6-month intervals would not seem to be sufficiently reliable in detecting the development of invasive lentigo maligna melanoma before it becomes a life-threatening disease. Early surgical excision is the treatment of choice.     

[Artículo traducido] Serie de 14 casos de tratamiento con imiquimod tópico al 5% en lentigo maligno: modalidades terapéuticas y claves para detectar recidivas

Topical imiquimod has been used off-label as monotherapy or adjuvant treatment for lentigo maligna. Our aim is to describe treatment modalities, clinical outcomes, and management of recurrence in patients receiving imiquimod for lentigo maligna.Patients from our unit with lentigo maligna or lentigo maligna melanoma treated with imiquimod 5% as monotherapy or in combination with surgery were included in this study.Fourteen cases were recruited (85.7% lentigo maligna and 14.3% lentigo maligna melanoma). Eight patients (57.1%) received imiquimod without surgery, and six (42.9%) underwent narrow excision before beginning treatment. During the follow-up period, pigmentation reappeared in 6 patients (4 postinflammatory hyperpigmentation and 2 relapses). Relapses were managed with very narrow excision (1 mm margin) and retreatment with imiquimod 5%.All imiquimod modalities showed well-tolerated side effects and low recurrence rates, with long periods of follow-up. Imiquimod appears to be a versatile option for treating LM in suitable candidates.     

[Translated article] Update on Lentigo Maligna: Diagnostic Signs and Treatment

Lentigo maligna is an in situ cutaneous melanoma that arises in sun-damaged skin. Its most common presentation is a progressive, slow-growing, irregularly pigmented spot on the face of older patients. Although the exact percentage of lentigo maligna that progresses to invasive tumors is unknown, it is thought to lie between 2% and 5%. Both the clinical and histologic diagnosis of lentigo maligna can be challenging, especially in patients with early-stage or atypical disease. Treatment also holds challenges, because lesions are located in highly visible areas and are often large. Surgery can thus compromise cosmetic and sometimes functional outcomes. We review clinical and histopathological findings that can facilitate the diagnosis of lentigo maligna. We also examine treatment options, with a focus on surgery.     

Series of Fourteen Cases of Topical Imiquimod 5% in Lentigo Maligna: Treatment Modalities and Clues for Detecting Recurrences

Topical imiquimod has been used off-label as monotherapy or adjuvant treatment for lentigo maligna. Our aim is to describe treatment modalities, clinical outcomes, and management of recurrence in patients receiving imiquimod for lentigo maligna.Patients from our unit with lentigo maligna or lentigo maligna melanoma treated with imiquimod 5% as monotherapy or in combination with surgery were included in this study.Fourteen cases were recruited (85.7% lentigo maligna and 14.3% lentigo maligna melanoma). Eight patients (57.1%) received imiquimod without surgery, and six (42.9%) underwent narrow excision before beginning treatment. During the follow-up period, pigmentation reappeared in 6 patients (4 postinflammatory hyperpigmentation and 2 relapses). Relapses were managed with very narrow excision (1 mm margin) and retreatment with imiquimod 5%.All imiquimod modalities showed well-tolerated side effects and low recurrence rates, with long periods of follow-up. Imiquimod appears to be a versatile option for treating LM in suitable candidates.     

Imiquimod: a novel treatment for lentigo maligna

Lentigo maligna is the in situ phase of lentigo maligna melanoma, and if left untreated it may progress to invasive melanoma. It most commonly occurs on the exposed sites of the face and neck of middle-aged or elderly patients. Conventional surgery using a 5-10 mm margin is the recommended treatment; however, lesions can be quite large and surgical removal may involve extensive plastic repair. We report an elderly patient with a large lentigo maligna on the scalp who was reluctant to have surgery. We tried topical imiquimod 5% cream (Aldara), a local immunomodulator, which has recently become available for the treatment of external genital and perianal warts. Initially used over a test area and then over the whole of the lesion, for a total of 7 months, the imiquimod cream resulted in complete clinical and histological cure. The patient has been followed up for 9 months without evidence of recurrence.     

Rapid progression of lentigo maligna to deeply invasive lentigo maligna melanoma. Report of two cases

Two patients had lesions of lentigo maligna that evolved into deeply invasive (level 4-5) lentigo maligna melanoma during a relatively short period (two years and four years, respectively). In both patients, the clinical impression of lentigo maligna had been difficult to confirm by histopathologic analysis until the invasive tumor had developed. Both patients were actively followed up during this period of evolution, with our intention of detecting any early changes suggestive of invasive melanoma. Since deep invasion developed despite close clinical supervision, a more aggressive approach to the treatment of lentigo maligna may be warranted.     

Apparent progression of lentigo maligna to invasive melanoma during treatment with topical azelaic acid

Nine patients with lentigo maligna were treated with topical azelaic acid. Clinical improvement was observed in four, with complete clearing in one. Two patients developed invasive lentigo maligna melanoma while on treatment. Caution should be exercised in the use of topical azelaic acid in the treatment of lentigo maligna.     

Lentigo Maligna

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.     

Recurrent lentigo maligna as amelanotic lentigo maligna melanoma

Amelanotic lentigo maligna and lentigo maligna melanoma are extremely rare tumours. Even rarer is a recurrent amelanotic lentigo maligna or amelanotic lentigo maligna melanoma at the site of a previously removed pigmented lentigo maligna. We describe two cases of recurrent amelanotic lentigo maligna melanoma manifesting as erythematous plaques evolved from previously excised pigmented lentigo maligna.     

Immunocryosurgery as monotherapy for lentigo maligna or combined with surgical excision for lentigo maligna melanoma

The incidence of lentigo maligna (LM), in situ (LM) or invasive (lentigo maligna melanoma, LMM), has increased during the last decades. Due to functional or cosmetic outcomes, optimal treatment with surgical excision may not be appropriate in some cases. We tried less invasive therapy, immunocryosurgery, as a single treatment for LM or combined with surgery for LMM, with better aesthetic results. Three patients with LM or LMM not amenable to complete surgical excision were selected. LMM patients underwent limited surgical resection of the invasive area. Subsequently, a combined treatment with topical imiquimod and cryosurgery was performed. The LM patient received immunocryosurgery directly. All of them were free of local and systemic disease at 48, 42 and 41 months after discontinuation of therapy. We consider that immunocryosurgery is an alternative option for LM or even for LMM (after removal of the invasive tissue with narrow margins) in poor surgical candidates, with good therapeutic, functional and cosmetic results.     

Lentigo maligna treated with 5% imiquimod cream

Lentigo maligna (LM) is considered to be an in-situ stage of lentigo maligna melanoma. Clinically, it presents as a pigmented macule, irregular in shape and tone. 30% to 35% of untreated lentigo malignas can progress into lentigo maligna melanoma. The treatment of choice for this pathology is surgical excision with margins of 0.5 cm. of clinically normal skin around the lesion, or Mohs microsurgery. Imiquimod is a topical immunomodulator that stimulates both acquired and innate immunity. We present the case of a patient with LM, treated with 5% imiquimod cream, with an excellent therapeutic response.     

Amelanotic lentigo maligna and amelanotic lentigo maligna melanoma: a report of three cases mimicking intraepidermal squamous carcinoma

The clinical diagnosis of amelanotic melanoma may pose diagnostic difficulties. We report three cases of amelanotic lentigo maligna, two of which developed an invasive component (lentigo maligna melanoma). The clinical appearances in each case mimicked intraepidermal squamous carcinoma.     

Amelanotic lentigo maligna managed with topical imiquimod as immunotherapy

Clinically amelanotic lentigo maligna often resembles an inflammatory lesion rather than a melanoma in situ. We present two cases of extensive amelanotic lentigo maligna presenting as gradually enlarging erythematous patches on the faces of women following incomplete excisions of lentigo maligna. Because of their site and size, therapeutic options were limited; the lesions have, however, resolved (clinically and histologically) following the topical application of 5% imiquimod cream. We discuss the rationale for the use of imiquimod in the treatment of lentigo maligna.     

Lentigo maligna melanoma in situ with neurotropism

Perineural invasion, or neurotropism, is defined by the presence of cancer cells either within the neuronal sheath or found along the nerves. In melanoma, it is most commonly associated with invasive desmoplastic melanoma, a melanoma that is most commonly associated with malignant melanoma in situ, lentigo maligna type. Initially, perineural invasion was included in the reported Breslow thickness; however, recent data suggest that it should not be included. In this report, we describe a case of malignant melanoma in situ, lentigo maligna type, with associated neurotropism in the absence of invasive component.     

Histological evolution of lentiginous melanoma: a report of five new cases

BACKGROUND: The term lentiginous melanoma was recently used for atypical melanocytic proliferations sharing some histological features with lentigo maligna and associated with a protracted in situ stage before invasion. Lentiginous melanoma was characterized by predominantly single-cell lentiginous growth pattern with focal junctional nests and pagetoid spread, preservation of the dermoepidermal junction, limited cytological atypia, and lack of significant solar elastosis. We report five similar cases. METHODS: Histological review of routine sections with clinicopathological correlation. RESULTS: Three patients were male and two were female. The age at presentation ranged from 24 to 66 years. All lesions arose on the truck or proximal extremities. All five cases fulfilled histological criteria proposed for lentiginous melanoma. None of the lesions showed significant solar elastosis. One lesion was followed clinically and histologically for 16 years without intervening treatment. It had three local recurrences before culminating in invasive melanoma. CONCLUSIONS: Our observations support recent efforts to distinguish lentiginous melanoma as a distinct clinicopathological entity. Lentiginous melanoma can remain in situ for a long time before invasion and may be considered an analogue of lentigo maligna occurring on non-severely sun-damaged skin. Familiarity with the histological features of this variant is important for its early recognition and treatment.     

Cellular fine structure in the invasive nodules of different histogenetic types of malignant melanoma

Ultrastructural studies were carried out on the invasive nodule of forty malignant melanomas. The findings support the concept that the fine structure of lentigo maligna melanoma is often characteristic, and differs from that of superficial spreading and nodular melanoma. The melanosomes in lentigo maligna melanoma are usually ellipsoidal and resemble those of normal melanocytes, whereas the melanosomes in superficial spreading and nodular melanoma are most often spheroidal and abnormal in appearance. Superficial spreading and nodular melanomas cannot be distinguished reliably by their ultrastructure. Melanosomal appearances could not be related to the presence of a pre-existing naevus or the depth of invasion of the tumour nodule.     

Amelanotic lentigo maligna melanoma: a unique case and review of the literature

It has been estimated that 2 percent of all melanomas are clinically amelanotic, with amelanotic lentigo maligna melanoma being an even rarer presentation. These neoplasms have presented clinically as neurodermatitis, eczema, and erythema. Given the lack of clinical markers and subsequent delay in diagnosis of these lesions, they are potentially more dangerous than pigmented lentigo maligna melanomas. We report a case of an amelanotic lentigo maligna melanoma presenting as an ill-defined edematous area on the left cheek of an elderly woman.     

Lentigo Maligna: Review of Salient Characteristics and Management

Lentigo maligna is a melanocytic neoplasm, often regarded as ‘melanoma in situ,’ which may progress to lentigo maligna melanoma. Lentigo maligna clinically presents as a pigmented, asymmetric macule that originates on the head and neck and spreads slowly. 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. The differential diagnosis includes solar lentigo, seborrheic keratosis, lichen planus-like keratosis, pigmented actinic keratosis, and melanocytic nevus. Stains used in diagnosis include hematoxylin and eosin, HMB-45, MART-1/Melan-A, Mel-5, and S-100. Surgical excision is the preferred treatment for lentigo maligna. Second-line techniques include medical (topical imiquimod) and destructive therapy.     

Treatment of lentigo maligna

Lentigo maligna (LM) is the in situ phase of lentigo maligna melanoma (LMM) and, if left untreated, 30-50% of cases will progress to LMM, which is now thought to behave as aggressively as any other melanoma. Literature on the of treatment of LM including conventional surgery, micrographic Mohs surgery, cryosurgery, radiotherapy, electrodesiccation and curettage, 5-fluorouracil (5-FU), azelaic acid, retinoic acid and lasers are reviewed. It is concluded that micro-graphic Mohs surgery has the lowest recurrence rates and that conventional surgery, cryosurgery and radiotherapy all have recurrence rates in the order of 7-10%. Therefore, on the basis of the current literature available, all three of these methods could be recommended as primary treatment of LM. It is extremely important when choosing one of the above treatments that the physician is adequately trained in the appropriate technique and understands the limitation of the method used and the need for close follow up of the patient     

Dubreuilh melanoma: and epidemiologic and prognostic study

BACKGROUND: Lentigo maligna melanoma is a specific histoclinical type of melanoma. We studied the epidemiologic features of lentigo maligna melanoma (Dubreuilh's melanoma) and compared prognosis with other types of melanoma. PATIENTS AND METHODS: A retrospective review of 516 cases of cutaneous melanomas, seen from 1985 to 1997, identified 29 cases of lentigo maligna melanoma. Epidemiologic, clinical and prognostic data were collected using a common scoring system for all patients. The chi-squared test, univariate log rank analysis, Cox multiple regression model for multivariate analysis, and actuarial survival curves were applied. RESULTS: The 29 cases of lentigo maligna melanoma (16 women, 13 men) accounted for 5.9 p. 100 of all melanomas. Mean age at diagnosis was 73 years compared with 54 years for others melanomas. Predominant localization was head and neck. There was no prior history of nevi compared with 50 p. 100. Mean delay to diagnosis was 4 years versus 1 year. All patients have had an occupation with to sun exposure. Mean tumoral thickness was 2 mm. Survival was the same as for extensive superficial melanomas and better than for nodular melanomas. Multivariate analysis showed that prognosis was not better in case of lentigo maligna melanoma. Tumoral thickness was the main prognosis factor. DISCUSSION: Our findings confirmed the specific nature of lentigo maligna melanoma and suggested that sun exposure plays an important role. Multivariate analysis did not show that prognosis was any better in case of lentigo maligna melanoma than in other types of melanoma. The thickness of the tumor must be taken into account as for other melanomas.