Body-site distribution of common acquired melanocytic nevi associated with severe sunburns among children in Lithuania

BACKGROUND: The aim of this cross-sectional study is to provide information on subsite-specific densities of melanocytic nevi by age, sex, and in relation to the history of severe sunburns. MATERIALS AND METHODS: This study was conducted in Kaunas, Lithuania, on a sample of 484 children aged 1-2 years, 4-5 years, 9-10 years, and 14-15 years. The questionnaire provided information about the history of severe sunburns since birth. Site-specific numbers and densities of melanocytic nevi of all sizes and nevi 2 mm or greater were studied. We used log-linear and Poisson regression models to estimate the effects of age, sex, and severe sunburns on the nevus density. RESULTS: The predicted total body density of nevi shows a considerable increase up to the age of roughly 10 years. Thereafter, the density increase tapered off. Median densities of nevi were highest on the face. The median density of nevi on the upper arms is higher than on the forearms. Similarly, the median density of nevi on the thighs is higher than on the lower legs. Estimates of the relative nevus densities related to the history of severe sunburns tend to be small with the exception of the legs for nevi 2 mm or greater (relative nevus density = 2.09, 95% CI 1.49-2.93). CONCLUSION: Nevus densities are highest on maximally or intermittently sun-exposed skin areas. With the exception of the legs among women, the subsite-specific ranking of nevus densities among adolescents follows a similar ranking as the skin melanoma incidence in Lithuania.     

Melanocytic nevus density in Asian, Indo-Pakistani, and white children: the Vancouver Mole Study

Melanocytic nevus density in 378 Asian and 68 Indo-Pakistani school children 6 to 18 years of age was compared with that in 1146 white children of the same age range. At all ages, the number of melanocytic nevi 2 mm or larger per square meter of body surface area was substantially lower in Asians and Indo-Pakistanis than in white persons. Among white persons characteristics associated with a higher risk of cutaneous melanoma in adults, that is, light skin color, a propensity to burn rather than tan in the sun, and a history of numerous or severe sunburns, are also associated with the highest melanocytic nevus density in children. Examination of these same host pigmentation and sunburn factors among Asian children revealed no association with nevus density.     

Suntan, sunburn, and pigmentation factors and the frequency of acquired melanocytic nevi in children. Similarities to melanoma: the Vancouver Mole Study

The association between prevalence of benign melanocytic nevi and a number of skin cancer risk factors was examined among 913 white Vancouver (Canada) school children aged 6 to 18 years. Subjects with light skin, with a propensity to burn rather than tan in the sun, and with numerous or severe sunburns in the previous 5 years had significantly higher nevus counts than individuals without these characteristics. Subjects who acquired deeper tans tended to have fewer nevi than those who did not tan. Finally, children who freckled had higher nevus counts than those who did not freckle. These findings in children are similar to those seen in studies of malignant melanoma among adults and suggest that strategies to reduce melanoma incidence should begin with young children.     

Frequency of acquired melanonevocytic nevi and their relationship to skin complexion in 939 schoolchildren

In 939 schoolchildren aged 8-16 years skin complexion was determined by a system of seven categories Anamnestic data concerning tanning ability and history of sunburns, however, were not considered owing to their obvious unreliability in children. Mean nevus count was 17.97, was significantly higher in boys than in girls and increased with age. There was a clear relation of mean nevus number and skin complexion: in fair skin type nevi are most frequent, decreasing in number by increasing of pigment content. Additionally, children with freckles have higher mean nevus count in every category of skin complexion. All literature data critically reviewed as dealing with mean mole count are not comparable in several respects. In different races, however, such studies may serve as a basis for subsequent investigations concerning the questions of probably increasing number of melanonevocytic 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.     

Number of acquired melanocytic nevi in patients with melanoma and control subjects in Japan: Nevus count is a significant risk factor for nonacral melanoma but not for acral melanoma

BACKGROUND: Epidemiologic studies have suggested that number of acquired melanocytic nevi is a risk factor for melanoma development in Japanese as it is in white populations. However, there are only a few population-based studies on acquired nevi in Asian populations, and no epidemiologic study on relationship between number of acquired nevi and melanoma in Japanese populations has been reported. OBJECTIVE: The purpose of this study was to assess number, size, and distribution of acquired melanocytic nevi in a Japanese population. Particular attention was paid to evaluation of relationship between number of acquired nevi and development of nonacral or acral malignant melanoma. METHODS: In all, 82 patients with malignant melanoma and 600 control subjects were included in this study. All participants were Japanese. The number of acquired melanocytic nevi, 2 mm or larger in diameter, on the whole body except the scalp and genital areas was counted by experienced dermatologists. The participants were divided into 5 age categories (0-19, 20-39, 40-59, 60-79, and >80 years old) for the statistical analyses. This categorization adjusted the age and sex distribution between patients with melanomas and control subjects in 40- to 59-, 60- to 79-, and over 80-year-old groups. RESULTS: In the control Japanese population, the number of acquired melanocytic nevi on the whole body increased with age in 0- to 19-year-old age group and reached the highest number, 6.7 +/- 8.1/person, in 20- to 39-year-old group. In patients with nonacral melanoma, the number of acquired nevi on the whole body in 40- to 59- and 60- to 79-year-old groups was significantly higher than that of the corresponding control group. In contrast, the rate of individuals who had acquired nevi on soles, palms, and nail apparatus was not significantly different between acral melanoma group and the control group in 40- to 59- and 60- to 79-year-old groups. CONCLUSION: This study has revealed that a large number of acquired melanocytic nevi is a risk factor for the development of nonacral melanoma in Japanese and white populations. However, acquired nevi on soles, palms, and nail apparatus do not seem to be a risk factor for acral melanoma in Japanese populations.     

Knowledge and Perception of Melanocytic Nevi and Sunburn in Young Children

Abstract: Background/Objectives: Understanding the public’s perception of nevi and sunburn is crucial to melanoma prevention efforts. Methods: We investigated the knowledge and perception of melanocytic nevi and sunburns in 77 children 6 to 10 years old (mean 8.2) in two elementary schools in Styria, Austria. The children were interviewed by specially trained psychologists about the number of their moles and how they felt having them. Additionally questions about sunburn history and sunburn perception were asked. The spontaneous answers of the children were recorded, there were no pregiven answers. Afterwards the children were examined by dermatologists clinically and with dermatoscopes. Results: The 96% of the children could describe a nevus (the term “mole” was translated to “nevus”) and 91% did not feel bothered about theirs. Only 26% had noted the appearance of new nevi within the last year. The 67% of all children had at least one sunburn and remembered the clinical features. The 20% of the children knew that sunburns could provoke skin cancer. All children felt comfortable during the clinical and dermatoscopic examination. Conclusion: Children aged from 6 to 10 years know exactly why they had suffered from sunburn, can describe the sunburn and how to avoid it. They do not feel bothered by their nevi and are alert to the appearance of new nevi.     

Number of melanocytic nevi as a major risk factor for malignant melanoma

A study of 121 melanoma patients and 139 control subjects from the University of California, San Francisco clinics was conducted among whites to examine the relationship between number of melanocytic nevi and cutaneous melanoma. Nevi that measured 2 mm or more in diameter were counted over the body by a dermatologist and a dermatology fellow. The average number of nondysplastic melanocytic nevi that were 2 mm or greater in diameter was 97 for melanoma patients and 36 for control subjects (p less than 0.001). Relative risks were 1.6 (p = 0.43) for 11 to 25 nevi, 4.4 (p = 0.01) for 26 to 50 nevi, 5.4 (p = 0.008) for 51 to 100 nevi, and 9.8 (p = 0.001) for more than 100 nondysplastic melanocytic nevi. Relative risks were 3.8 (p = 0.001) for 1 to 5 dysplastic nevi and 6.3 (p = 0.003) for 6 or more of these lesions. Report of blistering sunburns or of a previous skin cancer and having red or blond hair at the age of 20 were also independently associated with an increased risk of cutaneous melanoma. If confirmed in larger studies, the results presented on number of nevi and melanoma risk suggest a readily identifiable melanoma-prone group that could be followed to detect early malignant melanoma.     

Cutaneous melanoma in childhood and adolescence: an analysis of 36 patients

Analysis of data of 6931 patients with cutaneous melanoma seen at the Department of Dermatology and Allergology at the Ludwig-Maximilians-University of Munich between 1977 and 1998 identified 36 patients in whom cutaneous melanomas developed during childhood or adolescence (age <18 years). Clinical courses of all patients and histopathologic characteristics of the lesions were reviewed. Seventeen patients were boys and 19 patients were girls. The median ages of the boys and girls were 15 and 16 years, respectively (range, 2-17 years). Thirty-one patients presented with nonmetastatic primary melanomas and 5 patients presented with metastatic melanoma. Forty-seven percent of the primary lesions were associated with a nevus (22% with congenital nevi and 25% with acquired nevi). Tumor thickness ranged from 0.24 to 7.0 mm, with a median of 1.29 mm (mean, 1.67 mm). All patients with primary melanomas received surgical therapy; patients with metastatic disease received chemotherapy, radiation therapy, or both. Relative 5-year survival was 87.5% for the group of patients younger than 18 years. Similar to experience in adult patients, survival strongly correlated with tumor thickness and clinical stage at the time of diagnosis. The data emphasize that a high index of suspicion for cutaneous melanoma is needed by clinicians assessing melanocytic lesions in children and adolescents for early diagnosis. Reduction of the melanoma mortality rate in children and adolescents will be achieved through identification of patients at increased risk.     

Counts of Common and Atypical Melanocytic Nevi in Korean Young Men: Assessment of Their Risks and Correlations with Associated Factors

Two hundred and thirty-five Korean young men were examined for the count of melanocytic nevi (MN). The mean count of common MN of at least 2 mm diameter was 16.1. Three subjects had more than 50 common MN and another four had clinically atypical MN. We determined skin phototype by interview with questionnaires in the same persons as proposed by Fitzpatrick. All subjects were classified with respect to skin phototype and the number of previous sunburns. The correlations between common MN and the skin phototype or the number of previous sunburns were statistically analyzed. The skin phototype showed the correlation with the number of common MN, which means if skin phototype of any subject belongs to type I, he could to be predicted to have many more common MN than subjects with darker phototypes, like type VI. The correlation between number of previous sunburns and number of common MN was not statistically significant. This study shows persons at moderate risk of cutaneous melanoma (CM) do exist and skin phototype is associated with the prevalence of common MN in Koreans.     

Prevalence of common and atypical melanocytic nevi in Turkish children

The incidence of malignant melanoma is increasing rapidly in the white population of the world. Therefore, it is necessary to know the etiological factors of malignant melanoma and to take preventive measures in high-risk groups in different populations. This study aimed to estimate the prevalence of common melanocytic nevi (CMN) and atypical melanocytic nevi (AMN) and to identify some phenotypic factors (eye and hair color, skin type), gender, and age associated with CMN and AMN presence in primary school children in a Turkish population. In this study, 1491 children aged from 7-15 were examined. Brown-black discrete lesions of two millimeters or larger, with the exceptions of solar lentigo and ephelides, were counted as CMN. The CMN prevalence was 73.85%, and the AMN prevalence was 3.45%. The numbers of CMN and AMN were found to be higher in boys than in girls. While more CMN were present in the head and neck areas than in other anatomic regions, the number of AMN was higher on the ventral and dorsal trunk. Our study provides evidence for a significant relationship between specific characteristics, including skin type, age, gender and the number of CMN in our population. However, CMN is more frequent in children having a lighter skin type, and its number increases with age. The results of our study and further studies which take sun-exposure characteristics and pigmentary factors into account, may facilitate the determination of the other factors affecting nevus production and the development of further strategies for following and preventing cutaneous melanoma in our geographical area.     

The influence of painful sunburns and lifetime sun exposure on the risk of actinic keratoses,seborrheic warts,melanocytic nevi,atypical nevi,and skin cancer

Painful sunburns are implicated in the pathogenesis of squamous cell carcinoma, basal cell carcinoma, and malignant melanoma. Chronic exposure to ultraviolet radiation is known as the most important risk factor for the development of actinic keratoses and squamous cell carcinoma. The purpose of the study was to assess the effect of painful sunburns and lifetime sun exposure on the development of actinic keratoses and seborrheic warts in relation to the development of squamous cell carcinoma and basal cell carcinoma, and on the development of melanocytic nevi and atypical nevi in relation to the development of malignant melanoma. We made use of a cohort of 966 individuals who participated in a case-control study to investigate environmental and genetic risk factors for skin cancer. Exposure measurements for sunlight were collected and actinic keratoses, seborrheic warts, melanocytic nevi, and atypical nevi were counted. Relative risks were estimated using exposure odds ratios from cross-tabulation. Multivariate logistic regression was used to adjust for potential confounders. The recall of painful sunburns before the age of 20 y was associated with an increased risk of squamous cell carcinoma, nodular basal cell carcinoma, and multifocal superficial basal cell carcinoma as well as actinic keratoses. Odds ratios with 95% confidence intervals adjusted for age, sex, and skin type were 1.5 (0.97; 2.3); 1.6 (1.1; 2.2); 2.6 (1.7; 3.8); and 1.9 (1.4; 2.6) for the three types of nonmelanoma skin cancer and actinic keratoses, respectively. Painful sunburns before the age of 20 y were also associated with an increased risk of malignant melanoma and the development of its precursors, melanocytic nevi and atypical nevi. Odds ratios with 95% confidence intervals adjusted for age, sex, and skin type were 1.4 (0.86; 2.1); 1.5 (1.1; 2.0); and 1.4 (0.88; 2.3) for malignant melanoma and the two types of precursors, respectively. Lifetime sun exposure was predominantly associated with an increased risk of squamous cell carcinoma (p-value for trend=0.03) and actinic keratoses (p-value for trend <0.0001) and to a lesser degree with the two types of basal cell carcinoma. By contrast, lifetime sun exposure appeared to be associated with a lower risk of malignant melanoma, despite the fact that lifetime sun exposure did not diminish the number of melanocytic nevi or atypical nevi. Neither painful sunburns nor lifetime sun exposure were associated with an increased risk of seborrheic warts.     

Cutaneous melanoma histologically associated with a nevus and melanoma de novo have a different profile of risk: results from a case-control study

BACKGROUND: Histopathologic association between melanocytic nevus and melanoma has been reported in approximately 10% to more than 50% of melanoma cases. Whether melanomas in contiguity with a nevus have a different natural history and pathogenesis from melanomas without a nevus is still to be determined. OBJECTIVE: The present study was undertaken to clarify whether melanocytic nevus-associated melanomas (MN[+]) have a different risk factor profile from cases without histopathologic evidence of melanocytic nevus association (MN[-]). METHODS: The study population consisted of 131 invasive melanoma cases with a thickness of 4.00 mm or less and 174 control cases without melanomas. The whole series was evaluated for the following risk factors: phenotypic traits; the number of common, atypical, and congenital nevus-like nevi; and freckling and history of sunburns. Melanoma cases were revised for the presence of associated melanocytic nevi. The analysis of risk factors was performed by a case-control approach comparing cases, classified by histologic association with nevus, to the group of controls. Possible differences in risk factor distribution between MN(+) cases and MN(-) cases were evaluated with a polychotomous logistic regression model and a likelihood ratio test for heterogeneity. RESULTS: Histopathologic association between melanocytic nevus and melanoma was found in 27 cases (20.6%). Phenotypic traits were shown to be more powerful predictors of risk for MN(-) than for MN(+) cases (blond/red hair; odds ratio, 7.4 and 1.2, respectively; likelihood ratio test for heterogeneity, 4.13; P < .05). Conversely, history of frequent sunburn was a risk factor only in MN(+) cases (more than 5 sunburns; odds ratio, 6.7; 95% confidence interval, 1.3-33.7), but not in MN(-) cases (odds ratio, 1.2; 95% confidence interval, 0.3-4.0; likelihood ratio test for heterogeneity, 4.2; P < .05). Where melanocytic nevi are concerned, an increased number of common nevi was a predictor of melanoma risk in both MN(+) and MN(-) cases, but with a different magnitude of risk, higher for MN(+) cases (number of common nevi, 10-30; odds ratio, 14.4 and 4.7, respectively; likelihood ratio test for heterogeneity, 3.7; P = .055). CONCLUSION: This study showed that, although MN(+) and MN(-) melanomas share many risk factors, there is a different strength of association between the 2 groups. The effect of a history of sunburn as a predictor of risk was found only for nevus-associated melanomas, suggesting a possible role of sunburns in the neoplastic transformation of nevi.     

Prevalence of melanocytic nevi in 8‐ to 10‐year‐old children in Southern Spain and analysis of associated factors

Background There is a known relationship between melanocytic nevi (MN) and cutaneous melanoma. MN are related to genetic and environmental factors, and the latter appear to be more important in childhood. Objectives To determine the prevalence of MN and its relationship with phenotypic traits and sun exposure habits in 8‐ to 10‐year‐old children. Subjects and methods We performed a cross‐sectional study of 8‐ to 10‐year‐old primary school children in the city of Granada (Spain), gathering data on phenotypic traits, sun protection measures, sunburn frequency and the number and density of MN. Results We detected a mean of 19.38 MN per child, predominantly <2 mm in diameter. MN count was associated with low phototype, and was higher in boys vs. girls with low phototype. MN were more numerous with higher age. The largest number of MN of all sizes was detected in 10‐year‐old boys. MN were most frequently located on the torso and other sites intermittently exposed to sunlight. Conclusions A higher MN count is associated with lower phototype (blonde hair and fair skin) and higher age. The mean number of MN, including those of smaller size (<2 mm), was elevated in our series, especially on intermittently exposed sites.     

Paediatric melanoma

Paediatric melanoma, although rare, is the most common skin cancer in children. Our current knowledge on paediatric melanoma incidence trends is expanding, as several studies have addressed this issue with conflicting results. Known risk factors for paediatric melanoma include family history of melanoma, a previous history of malignancy, large congenital nevi, numerous melanocytic nevi, sunburns, increased UV exposure and a sun‐sensitive phenotype. In younger children, melanoma more often presents with atypical features, such as a changing, amelanotic or uniformly coloured, often bleeding lesion, not fulfilling in most cases the conventional ABCDE criteria. The major differential diagnoses are melanocytic nevi, proliferative nodules in congenital nevi and atypical Spitz tumours. Moreover, in the younger age group non‐Caucasian children are over‐represented, tumours tend to be thicker and lymph nodes are often involved. Despite the frequent diagnosis at an advanced stage, the overall survival is fair in paediatric melanoma. Specific guidelines for management of melanoma in children do not exist, and most often the disease is treated similarly to melanoma in adults.     

Common acquired melanocytic nevi, dysplastic melanocytic nevi and malignant melanomas: an image analysis cytometric study

We used computerized image analysis cytometry in analyze 10 melanocytic lesions from each of the following categories: common acquired nevi, melanocytic nevi with architectural features of dysplasia, dysplastic melanocytic nevi (DMN) with slight atypia, DMN with moderate atypia, DMN with severe atypia, and superficial spreading melanomas. The nuclei of at least 50 consecutive nevomelanocytes in the most atypical zones were digitized at ×1000 under oil immersion, without knowledge of diagnosis by one observer. Grading of atypia was based on current practices as described in the literature. The results showed significant differences ( p < 0.05) in nuclear area and standard deviation of nuclear area between melanoma and DMN with severe atypia, and between DMN with severe atypia and all other categories of nevi. There were no differences among any lesions with respect to nuclear shape. No differences in nuclear area were found among DMN with moderate, or slight atypia, nevi with features of dysplasia, and typical nevi. These results show for the first time objective distinction of low-grade (slight-moderate atypia), and high-grade or severe atypia in pre-malignant nevomelanocytic lesions of the skin.     

Melanocytic Nevi in Turner Syndrome

Abstract: One morphologic feature of Turner syndrome is increased number of melanocytic nevi; however, little attention has been given to their characterization. The development of a melanoma in one of our patients with Turner syndrome prompted this study. We prospectively examined 10 patients with the disease, confirmed by karyotype. all patients underwent full body skin examination noting the number, size distribution, and degree of clinical atypia of melanocytic nevi. Representative and unusual lesions were photographed. An average of 115 nevi were seen, with the majority measuring 1 to 5 mm. Most were located on the back and extremities. Clinical atypia was uncommon. our patients had larger numbers of benign-appearing nevi than the general population. Large numbers of melanocytic nevi is a risk factor for melanoma, suggesting that these patients have an increase in one risk factor. Longitudinal studies are indicated to clarify this issue; nevertheless, we recommend periodic skin examinations and the regular use of sunscreens for individuals with Turner syndrome.     

Clinical diagnosis of dysplastic melanocytic nevi: A clinicopathologic correlation

A prospective, community practice-based, clinicopathologic correlation was undertaken in 165 melanocytic nevi excised from a group of forty-three patients, each patient having previously had at least one clinically suspected and histologically confirmed dysplastic melanocytic nevus. Eighty-two percent of seventy-two lesions with histologic evidence of mild dysplasia had been diagnosed correctly as such clinically. The accuracy of clinical diagnosis of moderate dysplasia was low (20%); however, all cases of severe dysplasia with or without in situ melanoma were diagnosed correctly. In 75% of all cases in which dysplasia of any degree was diagnosed clinically, histologic evidence of dysplasia was found. In order to investigate further the clinical features of these nevi, 175 color enlargements of histologically confirmed dysplastic melanocytic nevi were examined. The following clinical features were found to be most common: ill-defined border (90%), irregularly distributed pigmentation (84%), maximum diameter greater than 5.0 mm (72%), erythema (64%), and accentuated skin markings (63%). Increasing darkness and confluence of pigmentation in these dysplastic melanocytic nevi correlated with increasing severity of dysplasia. We conclude that careful clinical examination of individual melanocytic nevi will separate severe dysplasia with or without in situ melanoma from low-grade (mild or moderate) dysplasia in a high percentage of nevi from patients with the dysplastic nevus syndrome. Clinical examination will yield a diagnosis of dysplasia in approximately 75% of nevi from such patients in whom histologic evidence of dysplasia is present. Clinical examination constitutes a practical and sufficiently reliable method for the assessment of melanocytic nevi in patients with the dysplastic nevus syndrome.     

Prevalence of skin disorders in school children in Ibadan, Nigeria

Although skin diseases are common in children, there are very few population-based studies in West Africa. Recently, there has been considerable emphasis on hygiene and socio-economic impact on the incidence of allergic disorders in children. We determined the prevalence of skin diseases in a public primary school in Ibadan (southwest Nigeria). A questionnaire for assessing factors associated with the prevalence of diseases was completed, and a complete physical examination was carried out on 1066 students. The study included 529 (49.6%) boys and 537 (50.4%) girls with a mean age of 8.8 +/- 2.5 years. The mean family size of the subjects was 6.7 +/- 2.3 while the mean number of rooms in their homes was 2.6 +/- 1.45. Infectious dermatosis was commonly observed. Of 375 children with a skin lesion, 162 (15.2%) had dermatophytosis, most often tinea capitis, 50 (4.7%) had pityriasis versicolor, and 50 (4.7%) had scabies. Other dermatoses observed included papular urticaria in 35 (3.3%) and angular cheilitis in 27 (2.5%) children. One or more melanocytic nevi were found in 40 (3.8%) children while 138 (12.9%) and 77 (7.25%) had tribal and scarification marks, respectively. Atopic eczema and viral warts were virtually absent. We concluded that fungal infections and scabies were the most common skin diseases in our study population, whereas allergic illnesses were nearly absent.