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.     

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.     

Amelanotic lentigo maligna melanoma manifesting as a dermatitislike plaque

A 72-year-old man with a previous history of an amelanotic melanoma on his left forearm had an erythematous plaque excised from his right shoulder. Although the clinical impression was a dermatitis, a biopsy specimen revealed an amelanotic lentigo maligna melanoma. To our knowledge, this is the first patient described with an amelanotic lentigo maligna melanoma as a second primary tumor to an apparent previous amelanotic melanoma, manifesting as a dermatitislike plaque.     

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.     

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.     

Macular amelanotic melanoma in situ

This report aims at directing the attention to the rare entity of amelanotic melanoma in situ, as exemplified in a patient who had an amelanotic lentigo maligna 10 years ago and a recurrent lesion of identical clinical and histological (except for pagetoid tumor cells in the epidermis) appearance 4 years ago. Amelanotic melanomas in situ appear as inconspicuous reddish macules, which can hardly be diagnosed or even suspected on clinical grounds.     

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.     

Amelanotic malignant melanoma following cryosurgery for atypical lentigo maligna

Cryosurgery is an alternative treatment option to surgical excision for lentigo maligna. Clinical evidence of recurrence is usually characterized by repigmentation at the treated site. We report two patients who developed amelanotic malignant melanoma following cryosurgery for a pigmented lentigo maligna. These cases illustrate the potential risk of treating lentigo maligna with cryosurgery.     

A clinically invisible melanoma

We report a case of an amelanotic lentigo maligna incidentally found on a shave biopsy in an 87‐year‐old woman. Amelanotic lentigo maligna is a rare variant of lentigo maligna. It is often reported as presenting as erythematous scaly macules and is usually confused as benign dermatoses. Here were present a case of amelanotic lentigo maligna with no visible or palpable features.     

Desmoplastic melanoma associated with an intraepidermal lentiginous lesion: case report and literature review

Desmoplastic melanoma tends to present as firm, amelanotic papules. Microscopically, it reveals a proliferation of fusiform cells in the dermis and variable collagen deposition, as well as intraepidermal melanocytic proliferation of lentiginous type in most cases. Biopsy in a 61-year-old white male patient, who had received a diagnosis of lentigo maligna on his face 10 years before, revealed a proliferation of dermal pigmented spindle cells and collagen deposition, reaching the deep reticular dermis, with a lentiginous component. Immunohistochemistry with S-100, Melan-A and WT1 showed positivity, but it was weak with HMB45. Desmoplastic melanoma associated with lentigo maligna was diagnosed. Several authors discuss whether desmoplastic melanoma represents a progression from the lentiginous component or arises "de novo". Desmoplastic melanoma represents a minority of cases of primary cutaneous melanoma (less than 4%). Identification of lentigo maligna indicates that desmoplastic melanoma should be carefully investigated.     

Altersmelanome (LM, LMM) an beiden Wangen Analyse der unterschiedlichen Wachstumsdynamik anhand photokatamnestischer Befunde

The dynamics of tumor growth of malignant melanoma may be reconstructed by evaluation of suitable private photographs of the patient. Photohistorical investigations can greatly aid in following the course of development of malignant melanomas and show impressively the slow and protracted growth of initial melanomas. We report on a 90-year-old patient with an in situ melanoma (lentigo maligna) and an invasive lentigo maligna melanoma in the facial region. We were able to obtain complete series of photographs from this patient, which show the different development of the two melanomas over a period of more than 30 years. The first tumor to appear developed very slowly while the later one showed invasive growth after a short time period. Development of multiple primary melanomas is a well recognized phenomenon. The presence of multiple primary melanomas does not appear to be a negative prognostic factor. However, patients with primary melanoma should be made aware of increased risk of development another primary and physicians should do careful total body skin examinations for new primary melanomas as well as for recurrences of the original melanoma.     

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.     

Actualización en el diagnóstico y manejo del melanoma desmoplásico

Desmoplastic melanoma (DM) accounts for 0.4% to 4% of all melanomas. These skin tumors are mainly formed by amelanotic spindled melanocytes immersed in an abundant collagen stroma and are classified as pure when the desmoplastic component accounts for at least 90% of the invasive tumor and as mixed or combined otherwise. DMs are more common in men (male to female ratio, 1.7 to 2:1), and the mean age at diagnosis is 66 to 69 years. The tumors tend to occur in chronically sun-exposed areas, often in association with lentigo maligna, and are difficult to recognize because they can resemble a scar, presenting as a firm, unpigmented papule or plaque with poorly defined borders. DMs also have a strong tendency to recur locally, and pure variants rarely spread to the lymph nodes. Nonetheless, recently published series suggest that patients with DM have a similar prognosis to those with nondesmoplastic melanoma of the same thickness. The clinical management of DM varies in certain aspects from that of other melanomas and is reviewed in this article.     

[Translated article] Update on the Diagnosis and Management of Desmoplastic Melanoma

Desmoplastic melanoma (DM) accounts for 0.4% to 4% of all melanomas. These skin tumors are mainly formed by amelanotic spindled melanocytes immersed in an abundant collagen stroma and are classified as pure when the desmoplastic component accounts for at least 90% of the invasive tumor and as mixed or combined otherwise. DMs are more common in men (male to female ratio, 1.7 to 2:1), and the mean age at diagnosis is 66 to 69 years. The tumors tend to occur in chronically sun-exposed areas, often in association with lentigo maligna, and are difficult to recognize because they can resemble a scar, presenting as a firm, unpigmented papule or plaque with poorly defined borders. DMs also have a strong tendency to recur locally, and pure variants rarely spread to the lymph nodes. Nonetheless, recently published series suggest that patients with DM have a similar prognosis to those with nondesmoplastic melanoma of the same thickness. The clinical management of DM varies in certain aspects from that of other melanomas and is reviewed in this article.     

Aggressive amelanotic lentigo maligna

A 66-year-old woman had a long-standing, scaly erythematous lesion on her left temple which histologically showed features of amelanotic lentigo maligna. It had recurred on numerous occasions over a period of 17 years, in spite of multiple attempts at curative surgery. There were also recurrences within a skin graft which, to our knowledge, has not been documented previously with lentigo maligna. In spite of the prolonged course, and extensive intraepidermal melanocytic proliferation amounting to melanoma in situ, there has been no evidence of dermal invasion. The lack of pigmentation in such lesions means that clinical definition of margins is highly inaccurate. In view of the aggressive horizontal growth phase of this lesion, with rapid recurrence following surgery, it was treated with electron beam therapy, and this has resulted in complete clinical remission. This most unusual case illustrates the potential difficulties in diagnosis and management of amelanotic lentigo maligna.     

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.     

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.     

Prolonged evolution of a lentigo maligna

Lentigo maligna (LM) is a melanocytic lesion which is a potential precursor to melanoma and often has a prolonged intraepidermal growth phase before evolving into lentigo maligna melanoma (LMM). LM is also noted for its tendency to locally recur after treatment. We present a patient who had a persistent LM on her left cheek which, despite multiple excisions, persisted and transformed into a partially amelanotic LMM roughly three decades later. Our patient's course was also notable for this melanoma recurring at the edge of, and subsequently migrating into, a previously placed skin graft.     

Surgical management of primary melanoma

Melanoma precursor lesions and stage I malignant melanomas are preferentially removed by excisional surgery. Several studies have supported the concept of a more conservative excision strategy. Reduced safety margins with a maximum of 2-3 cm enable us to cover most defects by simple skin flap techniques. In critical anatomical sites and in lentigo maligna melanoma micrographic surgery has recently gained importance. The value of adjuvant surgical procedures remains controversial. Possibly, the technique of sentinel-node-biopsy provides a better approach towards a more selective use of lymphadenectomy in patients with clinically occult micrometastases.