Epidermolysis bullosa nevus-like lesions in a pediatric patient with pyoderma gangrenosum.

Epidermolysis bullosa-associated nevi are recently described dysplastic nevi found in patients with epidermolysis bullosa. These lesions display clinical features of unusual nevi suggestive of malignancy but thus far cases with malignant transformation have not been reported. We describe a case of epidermolysis bullosa-type nevi developing in a child with pyoderma gangrenosum. The nevi in our patient were found in areas previously affected by pyoderma gangrenosum and were clinically concerning for malignancy. However, they were only moderately atypical on light and confocal microscopy. This case demonstrates that pediatric patients with cutaneous inflammation, bullae formation, or both, are at risk for developing unusual nevi at previous sites of skin involvement. Considering the absence of malignant change in these nevi, we suggest that close observation can be employed in cases where this diagnosis can be confirmed both clinically and microscopically.

Histopathologic diagnosis of dysplastic nevi: concordance among pathologists convened by the World Health Organization Melanoma Programme.

Dysplastic nevi are an important indicator of risk of cutaneous malignant melanoma. The study of and, particularly, international communication regarding this group of lesions have been hindered by a lack of precision in diagnosis. In an effort to broaden understanding, a panel of pathologists agreed upon a set of criteria for the diagnosis of dysplastic melanocytic nevi. Two major and four minor criteria were defined. The major criteria are (1) basilar proliferation of atypical nevomelanocytes (extending at least three rete ridges or "pegs" beyond any dermal nevo-cellular component), and (2) organization of this proliferation in a lentiginous or epithelioid-cell pattern. Minor criteria are (1) the presence of lamellar fibrosis or concentric eosinophilic fibrosis, (2) neovascularization, (3) inflammatory response, and (4) fusion of rete ridges. Diagnosis required presence of both major criteria and at least two minor criteria. One hundred fourteen histologic specimens of benign acquired nevi, dysplastic nevi, and radial-growth-phase melanomas were examined by the members of this panel; their diagnoses were compared to determine degree of concordance. The established criteria yielded 92% mean concordance overall.

Nodular histogenetic type -- the most significant factor for thick melanoma: implications for prevention.

Tumour thickness is the most important prognostic factor in malignant melanoma. To reduce the melanoma-related mortality, factors related to the presentation of thick melanoma have to be identified. Three samples of melanoma patients (n=694) were studied for this purpose. Histogenetic type was the only factor which differentiated between 'thin' (< or = 0.8 mm) and 'thick' (> 2.0 mm) lesions. During a 10-year period only 3% of the nodular lesions were 'thin' at diagnosis. Differences in knowledge about melanoma or the location of the lesion (either 'easy' or 'difficult' for the patient to observe) did not explain differences in tumour thickness. The most common tumour site irrespective of histogenetic type and gender was 'back of the trunk'. 'Increase in diameter' and 'bleeding' were the symptoms most frequently reported by patients with 'thick' melanoma. 'Thick' lesions were diagnosed in older age groups and in men to a greater extent. Considering these results, melanoma prevention should also be targeted to older age groups and attention should be paid to symptoms such as 'increase in diameter' even in the absence of other characteristic symptoms of melanoma. An increased proportion of nodular melanoma diagnosed as 'thin' lesions can be interpreted as a step forward in secondary prevention.

[Early diagnosis of cutaneous melanoma and its precursors. Importance of the clinical characteristics of thin melanoma]. / Diagnosi precoce del melanoma cutaneo e dei precursori. Importanza delle caratteristiche cliniche del melanoma sottile.

The diagnosis and removal of precursor and early lesions is the only method to improve the prognosis and survival rate in malignant melanomas of the skin since the aetiology of the disease is unknown and treatment ineffective when the neoplasm is diagnosed at an advanced stage. A campaign for the prevention and early diagnosis of melanoma is based on the health education of the entire population with the distribution of illustrative material that by teaching people to examine their skin will show up suspicious pigmentary lesions that can be examined and removed by the dermatologist. Thin melanoma is always curable when removed and constitutes the basic tumour to be described to the public as it is easily identified and has constant, typical features. Among the precursors the most interesting lesions is the sporadic or familial dysplastic nevus despite the controversy over its pathogenic significance and morphological aspect. The other pigmentary neoplasias (congenital and acquired nevus) only must to be removed when they present changes resembling thin melanoma.

A case of dysplastic nevus of the external auditory canal presenting with conductive hearing loss.

A nevus which is a benign melanocytic neoplasm rarely occurs within the external auditory canal (EAC). A dysplastic nevus presents atypical features both clinically and histologically, and is important as a potential precursor for melanoma. We present a case of a 33-year-old female patient with a dysplastic nevus in her EAC. Physical examination revealed a protruding mass arising from the posterior wall of the left cartilaginous EAC. The mass showed clinically characteristic findings of a melanocytic nevus. The patient underwent excisional biopsy via a transcanal approach under local anesthesia. Histopathological examination revealed an intradermal nevus with atypical melanocytes without pleomorphism. There was no evidence of recurrence two years after surgical excision.

The familial dysplastic nevus syndrome. Natural history and the impact of screening on prognosis. A study of nine families in the Netherlands.

Since 1982, nine families with the dysplastic nevus syndrome have been identified in the Leiden area (The Netherlands). A total of 50 primary melanomas were diagnosed in 38 persons. Nineteen of these melanomas had been diagnosed before the start of the screening programme (category I), 11 were detected at the initial examination of the families (category II), and 20 were found during the course of follow-up (category III). To assess the effect of screening, we compared these categories with respect to the developmental stage of the melanomas. One of the 19 melanomas in category I, two of the 11 in category II and seven of the 20 in category III were melanoma in situ. The average thickness of the invasive melanomas in categories I, II and III was 1.75, 0.80 and 0.54 mm respectively. Sixteen of the 19 melanomas in category I (84%) were Clark III or IV, whereas 15 of the 20 melanomas in category III (75%) were Clark I or II. From these findings it may be concluded that screening can lead to the detection of melanomas at an earlier stage, which in turn can permit curative treatment and improvement of both prognosis and life expectancy. The need for supervision based on central registration of affected families to guarantee the continuity of screening is discussed.