Prevalence and clinical features of congenital melanocytic nevi in 1,000 Spanish newborns

BackgroundCongenital melanocytic nevus is a benign proliferation of melanocytes that is present at birth or develops in the first months of life. Although such lesions are common, few studies have analyzed their prevalence in Spain.ObjectivesThe aim of this study was to define the prevalence and most frequent anatomical areas affected by congenital melanocytic nevi in our health service area. We also analyzed the influence of maternal and neonatal factors in the development of these lesions.Patients and methodsWe performed a prospective study of 1000 consecutive neonates seen in the first 72 hours of life in the perinatology clinic of the Pediatrics Department of Hospital Arquitecto Marcide in Ferrol, Spain, recording specific maternal and neonatal variables and the size and site of congenital melanocytic nevi if present.ResultsFourteen infants (10 girls and 4 boys; 12 white European, 2 North African; 1.4% of the study population) presented at least 1 melanocytic nevus. None had more than 1 lesion. Eight of the nevi were located on the trunk, 2 on the face, 2 on the upper limbs, and 2 on the lower limbs. The diameter of the lesions was less than 1.5 cm in half of cases and between 1.5 and 3.5 cm in the remainder.ConclusionsThere was a higher prevalence of congenital melanocytic nevi in preterm infants, females, and nonwhite infants. Maternal age, number of previous pregnancies, and birth weight do not appear to influence the prevalence of these lesions.     

A recurrent melanocytic nevus phenomenon in the setting of Hailey–Hailey disease

Atypical acquired melanocytic nevi in patients with epidermolysis bullosa (EB) have been referred to as EB nevi and are considered to be a type of recurrent nevus with atypical but distinctive histopathologic findings. Herein, we describe an atypical nevus in a patient with Hailey–Hailey disease with different histopathologic findings from EB nevi because of presumably different pathogenesis. It is important to be aware that the recurrent nevi phenomenon can be seen in acantholytic conditions as well as blistering disorders, given these lesions may clinically resemble melanoma.     

Phenotypic and histologic characteristics of cutaneous melanoma in patients with melanocortin-1 receptor polymorphisms

BackgroundThe melanocortin-1 receptor (MC1R) is an important risk factor for melanoma due to its role in the production of melanin in response to sun exposure.ObjectivesTo analyze the phenotypic and histologic characteristics of cutaneous melanoma in patients carrying mutations in MC1R and assess the influence of sun exposure on the occurrence of melanoma.Material and methodsA total of 224 patients with a diagnosis of melanoma seen in the Department of Dermatology at Hospital General Universitario Gregorio Marañón in Madrid, Spain between September 2004 and December 2009 were included in the study. The genomic sequence of MC1R was analyzed by polymerase chain reaction.ResultsAt least one of the following MC1R variants was present in 58% of the patients: V60L, V92 M, I155T, R160W, D294H, and R163Q. Carriers of those variants had a history of sunburn (P = .018) and melanomas located on areas with intermittent sun exposure (P = .019), and the majority had a diagnosis of superficial spreading melanoma. These associations were especially significant in patients with the R160W and D294H variants. Carriers of R160W also had melanomas associated with melanocytic nevi (P = .028).ConclusionsThe results of our study suggest that there may be a relationship between the expression of certain MC1R variants and sun exposure, history of sunburn, and skin type. They also indicate a higher frequency of superficial spreading melanomas and melanomas associated with melanocytic nevi in patients carrying certain mutations in MC1R.     

Nevo de Spitz y otros tumores spitzoides en la infancia. Parte 1: aspectos clínicos,histológicos e inmunohistoquímicos

A Spitz nevus is a melanocytic neoplasm of epithelioid and/or spindle cells that usually appears in childhood. These lesions are by nature benign, but their features can sometimes make them difficult to distinguish from melanomas. Spitzoid melanocytic lesions have been grouped into 3 types in recent decades: Spitz nevi, atypical Spitz tumors, and spitzoid melanomas. Atypical Spitz tumors are spitzoid melanocytic proliferations that have atypical histopathologic features that are insufficient to support a diagnosis of melanoma. The malignant potential of these lesions is at present uncertain. This review examines the clinical, dermoscopic, and histopathologic features of this group of lesions.     

Dysplastic nevus syndrome with development of multiple melanomas. A surgical concept for prophylaxis

A 58‐year‐old man presented in 2001 with dysplastic nevus syndrome with at least 300 nevi and about 100 clinically highly atypical nevi. Three melanomas had been excised by a private dermatologist within the past year. We then removed two additional melanomas. Between 2002 and 2003, 117 nevi which were atypical on dermatoscopy were removed; most by horizontal (shave) excision. Adequate clinical and dermatoscopic control was not feasible due to the large number of atypical nevi. In order to reduce the number of nevus cells, we treated test sites with both dermabrasion and split‐thickness excision. The latter proved to be more efficient and was used to completely excise the skin of the back, as well as parts of the arms and chest in two sessions under general anesthesia. Wound healing was uneventful. Following these procedures, adequate clinical and dermatoscopic monitoring of the remaining nevi was possible and only a few had to be removed. No more melanomas appeared in the treated areas.     

Características clínicas de los pacientes con melanoma cutáneo en función de las variaciones en el gen del receptor 1 de la melanocortina (MC1R)

IntroductionPatients with cutaneous melanoma who are carriers of polymorphisms in the melanocortin 1 receptor gene (MC1R) have distinctive clinical characteristics. The objective of this study was to determine the clinical characteristics associated with differing degrees of functional impairment of the melanocortin 1 receptor, as determined by the number and type (R and r) of MC1R polymorphisms.Material and methodsIn total, 1044 consecutive patients with melanoma diagnosed in our hospital after January 2000 were selected from the melanoma database. These patients were divided into 3 groups according to a score based on nonsynonymous MC1R polymorphisms. The frequencies of epidemiologic, phenotypic, and histologic variables and personal and family history of cancer were compared.ResultsPatients with a score of 3 or more were more likely to develop melanoma before the age of 50 years (odds ratio [OR] = 1.47), have a tumor on the head or neck (OR = 3.04), have a history of basal cell carcinoma or cutaneous squamous cell carcinoma (OR = 1.70), have atypical nevi (OR = 1.74), and have nevi associated with the melanoma (OR = 1.87).ConclusionsThe use of a scoring system for MC1R polymorphisms allowed us to identify associations between the degree of functional impairment of the melanogenesis pathway and the clinical characteristics of the patients and melanoma presentation.     

Estudio multicéntrico de casos y controles sobre factores de riesgo de desarrollar un melanoma cutáneo en la Comunidad Valenciana

IntroductionIt is important to identify subgroups within the general population that have an elevated risk of developing cutaneous melanoma because preventive and early-detection measures are useful in this setting. The findings of most studies that have evaluated risk factors for cutaneous melanoma are of limited application in Spain because the populations studied have different pigmentary traits and are subject to different environmental factors.ObjectiveTo identify the phenotypic characteristics and amount of exposure to sunlight that constitute risk factors for cutaneous melanoma in the population of the Autonomous Community of Valencia, Spain.MethodsWe performed a multicenter observational case-control study. In total, the study included 242 patients with melanoma undergoing treatment in 5 hospitals and 173 controls enrolled from among the companions of the patients between January 2007 and June 2008. The information was collected by means of a standardized, validated questionnaire. The odds ratio (OR) was calculated for each variable and adjusted using a multiple logistic regression model.ResultsThe risk factors found to be statistically significant were skin phototypes I and II, blond or red hair, light eye color, abundant melanocytic nevi, and a personal history of actinic keratosis or nonmelanoma skin cancer. After the multivariate analysis, only blond or red hair (OR = 1.9), multiple melanocytic nevi (OR = 3.1), skin phototypes i and ii (OR = 2.1), and a personal history of actinic keratosis (OR = 3.5) or nonmelanoma skin cancer (OR = 8.1) maintained significance in the model as independent predictive variables for melanoma.ConclusionsOur study supports the importance of certain factors that indicate genetic predisposition (hair color and skin phototype) and environmental factors associated with exposure to sunlight. Patients with multiple acquired melanocytic nevi and patients with markers of chronic skin sun damage (actinic keratosis and nonmelanoma cancer) presented a significant increase in risk.     

Dermatoscopy turns histopathologist's attention to the suspicious area in melanocytic lesions

BACKGROUND: Histopathologically, the diagnosis of nevus-associated melanoma or melanoma close to a common nevus can be missed if the specimen is cut in a nonrepresentative area or if the section shows only the associated common nevus. OBJECTIVE: To find out whether dermatoscopy of suspicious areas within a nevus can improve the histological diagnosis of malignant melanocytic lesions of the skin. MATERIALS: The study was based on dermatoscopic images of more than 2000 benign and 115 malignant pigmented lesions and a collection of corresponding histopathologic slides. METHODS: The dermatoscopic images and the corresponding histopathologic diagnoses were compared. In case of differences, the histopathologic findings were reevaluated and compared with the dermatoscopic findings. RESULTS: Three cases were identified in which melanoma could have been histopathologically missed as a result of improper sectioning. After the dermatoscopic findings were evaluated, the specimens were reembedded and further sections were obtained. Finally, nevus-associated melanoma or melanoma close to a common nevus was diagnosed. CONCLUSIONS: Specific dermatoscopic patterns of malignancy can be found in highly suspicious areas, eg, broadened networks, radial streaming, pseudopods, or dots located at the periphery. The dermatoscopic-histopathologic correlation can improve the diagnosis of melanoma. Therefore, the clinician should point to the most suspicious area with a drawing or image, and the suspected diagnosis of melanoma and the history of the lesion should be also mentioned.     

Large atypical melanocytic nevi in recessive dystrophic epidermolysis bullosa: clinicopathological, ultrastructural, and dermoscopic study

A 3-year-old boy with recessive dystrophic epidermolysis bullosa developed a rapidly growing, large, acquired irregular melanocytic nevus on the lower aspect of the back. The lesion was clinically atypical and fulfilled the criteria for a malignant melanocytic proliferation. A complete surgical excision was performed. Histopathologic examination disclosed a compound melanocytic nevus without melanocytic atypia. Ultrastructural examination showed melanocytic cells located both at the roof and the floor of the blister. Several months later, three pigmentary lesions with a similar clinical appearance developed. Periodic clinical and dermoscopic examinations were recommended. Dermoscopic examination disclosed a globular pattern with brown globules and black dots distributed all over the lesions. The lesions also exhibited blue-greyish dots and multiple rounded white structures corresponding to milia-like cysts. No dermoscopic features suggestive of malignancy were noted. Acquired melanocytic nevi showing atypical clinical features have been reported to occur in areas of blistering in patients with epidermolysis bullosa. These nevi appear as large, asymmetrical pigmentary lesions with irregular borders. Initially, they are very dark in pigmentation, with color variegation and loss of pigment, and even becoming papillomatous over time. Histopathologic examination can show features of compound/junctional nevus as well as persistent/recurrent nevus. The concept of "epidermolysis bullosa nevus" has been proposed to define these peculiar lesions. The clinical, histopathologic and ultrastructural features of these nevi are reviewed. The usefulness of dermoscopic examination in the routine diagnosis and follow-up of these lesions are stressed.     

Nevus lentiginoso atípico. Estudio clínico-patológico de 14 casos

BackgroundAtypical lentiginous nevus (of the elderly) is a peculiar form of dysplastic nevus. Clinically, this condition can resemble malignant melanoma and histologically, it has a lentiginous pattern with variable degrees of atypia and an absence of dermal nests. These features may lead to an erroneous diagnosis of lentigo maligna melanoma or lentiginous melanoma.Material and methodsWe reviewed 14 cases of atypical lentiginous nevus diagnosed at the dermatology department of Hospital General de Valencia in Valencia, Spain between December 2007 and March 2009. We studied the clinical and histopathologic features of the lesions after hematoxylin-eosin, Melan-A, and Ki-67 staining and compared our results to data reported in the literature.ResultsFour (28%) of the 14 patients (7 men, 7 women) were under 50 years of age. Clinically, most of the lesions (8/14) resembled atypical nevi and they were all located on the back. Histologically, they all had irregular lentiginous epidermal hyperplasia, with a proliferation of individual melanocytes only in the basal layer of the epidermis and an absence of dermal nests. Focal upward migration of melanocytes into the epidermis was present in just 4 cases. All the lesions had cellular atypia, which was moderate in 85% of cases. The Ki-67 proliferation index was low (<5%) in all the lesions analyzed.ConclusionsAtypical lentiginous nevi, which can be classified as atypical pigmented lesions with a lentiginous pattern, may clinically and histologically resemble melanoma. Our findings support earlier reports that both clinical and histologic findings may suggest a diagnosis of dysplastic nevus. All of the patients in our series are healthy and free of recurrence after 18 months or longer.     

Dermatoscopy of "dysplastic nevi": a beacon in diagnostic darkness

The sequential progression model for melanocytic tumours from common nevus to malignant melanoma was proposed by Clark almost 30 years ago. The "dysplastic nevus" has frequently been considered a logical offspring of this concept and as a direct precursor of melanoma, analogous to the epithelial dysplasia-carcinoma sequence. Despite the use of modern molecular methods, there is no consensus as to if the dysplastic nevus represents a true precursor lesion of melanoma, a separate distinct type of nevus, or a diagnostic dilemma. Currently, the concept of melanocytic dysplasia remains subject to confusing definitions at all levels of the diagnostic process, i.e. clinical appearance, dermatohistopathology, and molecular biology. In this review, we collect evidence that nevi fulfilling Clark and Elder's classic histological criteria mostly represent "endpoints" of nevocytic evolution, whereas a minority of "dysplastic nevi" represent true melanoma precursors. The unsolved dilemma is that neither clinical, histopathological nor molecular criteria exist to make a distinction between dysplastic nevi and early melanomas. Our analysis of the current knowledge on dysplastic nevi shows that dermatoscopy remains the only quantifiable, easily applicable and reproducible diagnostic tool to approach the problem. Due to a "quantum leap" in optical resolution, objective scores can be established, e.g. the total dermatoscopy score (TDS) according to the ABCD rule, and documentation of changes over time are possible by digital image storage devices. Although dermatoscopy does not solve the dilemma of discriminating early, basically feature-less melanomas from dysplastic nevi, and it does not prove that dysplastic nevus is a distinct entity, it helps make melanocytic tumours with unclear malignant potential a manageable disease.     

Increased Melanocytic Nevi in Patients with Inherited Ichthyoses: Report of a Previously Undescribed Association

Abstract: Ichthyosis is a heterogeneous cornification disorder. Melanocytic lesions have not been previously described in association with ichthyosis. Their clinical importance lies in the fact that they may simulate melanoma clinically and dermoscopically, as seen in epidermolysis bullosa. The objective of this study was to evaluate the clinical, dermoscopic, and histopathologic features of nevi and lentigines in 16 patients with autosomal recessive congenital ichthyosis—lamellar ichthyosis and nonbullous ichthyosiform congenital erythroderma. Patients underwent general clinical examination dermoscopy. The more suspicious lesions were excised and to histopathologic examination. Most patients (n = 13) reported no personal or familial history of melanoma or atypical nevi. All of the patients had at least five atypical melanocytic lesions. Ten of the 16 patients had at least one atypical nevus or lentigo. This study suggests that increased atypical melanocytic nevi may be a feature of long‐standing congenital ichthyoses. Whether this finding is disease‐related or a coincidental observation is difficult to ascertain. As an unequivocal discrimination from malignant melanoma in vivo is not always possible, regular clinical follow‐up of patients with ichthyosis and increased or unusual nevi is recommended.     

Dysplastic nevus (atypical nevus)

Atypical nevum (dysplastic) is considered an important factor associated with increased risk of developing cutaneous melanoma. It is believed that atypical nevi are precursor lesions of cutaneous melanoma. They may be present in patients with multiple melanocytic nevi (atypical nevus syndrome) or isolated and in small numbers in a non-familial context. The disease usually begins at puberty and predominates in young people. It has a predilection for sun-exposed areas, especially the trunk. The major challenge in relation to atypical nevi lies in the controversy of defining its nomenclature, clinical diagnosis, dermoscopic criteria, histopathological diagnosis and molecular aspects. This review aims at bringing knowledge, facilitating comprehension and clarifying doubts about atypical nevus.     

Giant congenital nevus with progressive sclerodermoid reaction in a newborn

Giant congenital melanocytic nevi are a rare occurrence in the pediatric population. The risk of malignant transformation associated with these lesions has been well established; however, the management strategies for giant congenital nevi remain controversial. We report an unusual sclerodermoid reaction in a giant congenital nevus in a 6-week-old Caucasian girl. Given its abnormal clinical appearance, the entire lesion was excised. The histology was consistent with an atypical compound/sclerosing spindle and epithelioid cell congenital nevus. No evidence of malignant change was seen histologically. The incidence of malignant transformation in giant congenital nevi has been difficult to calculate. Review of the literature yields an incidence of between 4 and 9%, favoring surgical excision of these lesions where possible. Atypical presentations of giant congenital nevi are rare, and we have found no other reported cases with a stromal change similar to that seen in our patient. We hypothesize that this change may represent an atypical host reaction to the nevus cells.     

The use of digital dermoscopy in the surveillance of melanocytic skin lesions: A real-life retrospective study comparing university hospital and private practices

BackgroundFew studies have evaluated the role of digital dermoscopy (DD) in the surveillance of pigmented lesions in real-life practice.Patients and methodsPatients followed with DD by 4 hospital dermatologists (group 1) and 4 private dermatologists (group 2) were retrospectively included if they had had at least 2 DD examinations for a minimum of 4 pigmented lesions. Their characteristics, risk factors, history of excision of benign nevi and melanomas prior to and during the DD follow-up, and characteristics of detected melanomas, were recorded.ResultsOne hundred and ninety-six patients were included in group 1 and 205 in groups 2. A family history of melanoma (25% vs. 12%, p < 0.01), a personal history of melanoma before DD follow-up (47% vs. 15%, p < 0.01), and a family (3% vs. 0%, p = 0.01) and personal (8% vs. 1%, p < 0.01) germline CDKN2a mutation were more frequent in group 1 than in group 2. In both groups, the number of excisions of benign lesions was higher before DD follow-up (380 and 347, respectively) than during DD follow-up (194 and 132). During follow-up, 29 melanomas were detected in group 1, with a median Breslow thickness of 0.4 mm, versus 1.3 mm for melanomas diagnosed before DD follow-up (p < 0.02). In group 2, 4 melanoma and 5 superficial atypical melanocytic proliferations of unknown significance were detected. The median Breslow thickness of newly diagnosed melanomas was 0.35 mm vs. 0.6 mm before DD follow-up (p = 0.1).ConclusionIn both populations in real-life practice, DD seemed to allow the detection of thin melanomas and to decrease the rate of “futile” resections.     

Comparison of dermatoscopic diagnostic algorithms based on calculation: The ABCD rule of dermatoscopy,the seven‐point checklist,the three‐point checklist and the CASH algorithm in dermatoscopic evaluation of melanocytic lesions

Dermatoscopic analysis of melanocytic lesions using the CASH algorithm has rarely been described in the literature. The purpose of this study was to compare the sensitivity, specificity, and diagnostic accuracy rates of the ABCD rule of dermatoscopy, the seven‐point checklist, the three‐point checklist, and the CASH algorithm in the diagnosis and dermatoscopic evaluation of melanocytic lesions on the hairy skin. One hundred and fifteen melanocytic lesions of 115 patients were examined retrospectively using dermatoscopic images and compared with the histopathologic diagnosis. Four dermatoscopic algorithms were carried out for all lesions. The ABCD rule of dermatoscopy showed sensitivity of 91.6%, specificity of 60.4%, and diagnostic accuracy of 66.9%. The seven‐point checklist showed sensitivity, specificity, and diagnostic accuracy of 87.5, 65.9, and 70.4%, respectively; the three‐point checklist 79.1, 62.6, 66%; and the CASH algorithm 91.6, 64.8, and 70.4%, respectively. To our knowledge, this is the first study that compares the sensitivity, specificity and diagnostic accuracy of the ABCD rule of dermatoscopy, the three‐point checklist, the seven‐point checklist, and the CASH algorithm for the diagnosis of melanocytic lesions on the hairy skin. In our study, the ABCD rule of dermatoscopy and the CASH algorithm showed the highest sensitivity for the diagnosis of melanoma.     

Dysplastic changes in different types of melanocytic nevi. A unifying concept

We observed histopathologic changes previously described in dysplastic melanocytic nevi in association with a dermal component characteristic of other types of melanocytic nevi or overlapping with features of other varieties of nevi. In order to determine the frequency of these changes, we studied 2,164 cases of compound melanocytic nevi that fulfilled the histopathologic criteria for the diagnosis of compound dysplastic nevus, including architectural pattern, cytologic features, and mesenchymal changes. Of the 2,164 compound dysplastic melanocytic nevi, 1,895 (87.6%) had the histopathologic characteristics previously described for dysplastic nevus, 179 (8.3%) showed a dermal component with a congenital pattern, 67 (3.1%) demonstrated epidermal and dermal characteristics of Spitz's nevus, 8 (0.3%) had features of a combined blue nevus, 13 (0.6%) had a halo phenomenon and 2 (0.1%) showed dermal neuronevus. By considering these nevi as variants of dysplastic nevi, one may apply a unified conceptual basis for their nomenclature. In order to completely describe the appearance of the nevus, we named them by adding the term "dysplastic", to their main histopathologic subtype. Accordingly, six different varieties of dysplastic nevi were identified: 1) dysplastic nevus (original); 2) dysplastic nevus with a congenital pattern; 3) dysplastic Spitz's nevus; 4) dysplastic combined blue nevus; 5) dysplastic halo nevus; and 6) dysplastic neuronevus. In summary, we conclude that the histopathologic criteria previously reported for the diagnosis of dysplastic nevi may be found in association with a dermal component characteristic of other types of melanocytic nevi or may have overlapping features with other variants of nevi.     

Melanocytic nevi in 2783 children and adolescents in Turkey

Abstract:  This study investigated the numbers of melanocytic nevi in Turkish children and adolescents. The research was conducted on 2783 subjects (age range, 7–14 yrs) at three elementary schools in Malatya, Turkey (latitude 38°N). Numbers of melanocytic nevi per subject were counted using a standard international protocol. Comparisons were made with subjects categorized according to age, sex and skin type. The mean melanocytic nevus count was 1.07 ± 2.37. A significant positive correlation was found between nevus count and age (p < 0.001). The mean count for boys was significantly higher than that for girls (p   < 0.001). Subjects with skin type II had a higher mean melanocytic nevus count than the other three groups. This is the first study related to numbers of melanocytic nevi in Turkey. The findings reveal that Turkish children and adolescents have few melanocytic nevi compared to those elsewhere in the world. In line with previous reports on other populations, analysis showed that older age, skin type II, and male sex are associated with higher melanocytic nevus counts. The results underline the importance of ethnic background in melanocytic nevus development.