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1.
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.  相似文献   

2.
OBJECTIVE: To evaluate the prevalence of common acquired melanocytic nevi and its relationship with pigmentary characteristics and severe sunburns in children. DESIGN: Cross-sectional study. SETTING: Kaunas city, Lithuania (latitude of 55 degrees 55 minutes). PATIENTS: A random sample of 484 children aged 1 to 2 years, 4 to 5 years, and 9 to 10 years and adolescents aged 14 to 15 years. INTERVENTIONS: A questionnaire that provided information about the history of sunbathing and skin type. MAIN OUTCOME MEASURES: Atypical melanocytic nevi were defined according to the clinical criteria of the ABCDE rule. RESULTS: The median number of all common acquired melanocytic nevi was 12 in boys and 11 in girls; the median number of melanocytic nevi 2 mm or larger in boys and girls was 4. Twenty-seven percent of children experienced severe sunburns more than once. After adjustment for age and sex, it was found that children who had severe sunburns in summer and skin type I had a higher density of all melanocytic nevi and melanocytic nevi 2 mm or larger. The prevalence of atypical melanocytic nevi was 7% in all children and was age dependent (age 4-5 years, 1%; 9-10 years, 4%; 14-15 years, 16%). Three percent of children had congenital melanocytic nevi. CONCLUSIONS: The total number of common acquired melanocytic nevi in children increased with age. There was a positive association between severe sunburns, the tendency of the skin to burn, and the number of all melanocytic nevi and nevi 2 mm or larger.  相似文献   

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BACKGROUND: Epidermolytic hyperkeratosis (EH) and focal acantholytic dyskeratosis (FAD) are distinct histologic patterns that have been observed incidentally in a variety of benign and malignant skin lesions, including melanocytic lesions. OBJECTIVE: Our motivation for this study was to determine whether FAD and/or EH was significantly associated with atypical melanocytic lesions. METHODS: Skin biopsy specimens of melanocytic lesions diagnosed at our facility over a 3-month period were examined for the occurrence of FAD and EH. RESULTS: Whereas both FAD and EH are uncommon findings, FAD was statistically increased in atypical melanocytic lesions (P =.0172). EH was not found to differ significantly in common acquired melanocytic nevi vs atypical melanocytic lesions. CONCLUSIONS: Although both can be found in association with nonneoplastic skin diseases, as well as cutaneous neoplasms, FAD, but not EH, might serve as a marker for melanocytic atypia. Taken together with findings in the literature, FAD might serve as marker for atypical cutaneous proliferations as a whole.  相似文献   

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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.  相似文献   

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OBJECTIVE: To analyze the frequency and characteristics of enlarging common melanocytic nevi. DESIGN: Cohort study using digital epiluminescence microscopy (ELM) for documentation and follow-up, with a median follow-up interval of 11.4 months. SETTING: A dermatology department at a university hospital in Vienna, Austria. PATIENTS: One thousand six hundred twelve melanocytic nevi appearing clinically as common nevi, obtained from 385 patients (mean [+/-SD] age, 34.2 +/- 14.8 y; 55.6% female). INTERVENTIONS: Follow-up examination and documentation by digital ELM. MAIN OUTCOME MEASURES: Frequency of enlarging nevi according to age and comparison of ELM features observed in enlarging and nonenlarging nevi. RESULTS: Enlargement was found in 5.3% (n = 86) of nevi. The frequency of enlarging nevi was inversely related to age (P<.001), in that enlarging nevi were common in patients younger than 20 years and relatively rare in older age groups. Epiluminescence microscopy revealed a peripheral rim of brown globules in 48.8% (n = 42) of enlarging nevi. In contrast, a peripheral rim of brown globules was found in only 0.7% (n = 11) of nevi without enlargement (P<.001). Enlarging nevi that were excised in children and adolescents showed no histological signs of atypia. In older age groups, 48.1% of excised enlarging nevi that were clinically diagnosed as common nevi showed some histological signs of atypia. None of the excised enlarging lesions was histologically diagnosed as melanoma. CONCLUSIONS: The frequency of enlarging common nevi is inversely related to age. In the absence of clinical signs of atypia, enlargement alone does not indicate malignancy. A peripheral rim of brown globules is a characteristic ELM feature of symmetrically enlarging melanocytic nevi.  相似文献   

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BACKGROUND: Conflicting evidence exists on the relation between sun exposure and the number of common acquired nevi. The increase in the number of common acquired nevi until early adulthood and their greater concentration on sun-exposed areas suggested that the growth of common acquired nevi is promoted by UV radiation. Nevertheless, it was noticed that although solar exposure accumulates with age, the number of common acquired nevi decreases after the third decade. OBJECTIVE: Our purpose was to examine the relation between the prevalence of common acquired nevi and accumulative sun exposure. METHODS: The number of common acquired nevi on 128 patients with multiple solar keratoses (SK) was compared with their number on 82 control subjects. The existence of SK served as a biologic marker for long-term solar effects. RESULTS: On patients with SK we counted 1285 nevi (mean 10.0 nevi per person) and on control subjects, 1521 nevi (mean 18.5 nevi) (p = 0.0046; Kruskal-Wallis test). The finding that persons exhibiting signs of accumulating sun effects have fewer nevi was maintained irrespective to differences of gender, occupation, and complexion. CONCLUSION: Our data suggest that accumulating solar effects may contribute to the natural maturation and elimination of common acquired nevi in late adulthood.  相似文献   

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BACKGROUND: Digital epiluminescence microscopy (DELM) has been reported to be a useful technique for the follow-up of melanocytic nevi. One of the promises of this technique is to identify modifications over time that indicate impending or incipient malignancy and to facilitate surveillance of melanocytic skin lesions, particularly in patients with multiple clinically atypical nevi. OBJECTIVE: Our purpose was to report on patterns of modifications over time observed in benign melanocytic skin lesions and melanoma. METHODS: A total of 1862 sequentially recorded DELM images of melanocytic lesions from 202 patients (mean age, 36.1 years; 54.0% female patients) with multiple clinically atypical nevi were included in the analysis. The median follow-up interval was 12. 6 months. Melanocytic lesions with substantial modifications over time (enlargement, changes in shape, regression, color changes or appearance of ELM structures known to be associated with melanoma) were excised and referred to histopathologic examination. RESULTS: A total of 75 melanocytic skin lesions (4.0%) from 52 patients (mean age, 33.3 years; 63.5% female patients) showed substantial modifications over time and were excised and referred to histopathologic examination. Eight changing lesions were histologically diagnosed as early melanomas. These lesions frequently showed focal enlargement associated with a change in shape as well as appearance of ELM structures that are known to be associated with melanoma. In contrast, the majority of benign changing lesions (common and atypical nevi) showed symmetric enlargement without substantial structural ELM changes. Six of the 8 patients in whom melanoma developed were unaware of the fact that the lesion had changed over time. CONCLUSION: We demonstrate that follow-up of melanocytic lesions with DELM helps to identify patterns of morphologic modifications typical for early melanoma. DELM may therefore serve as a useful tool to improve the surveillance of patients with multiple atypical nevi.  相似文献   

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We previously reported a single case of agminated acquired melanocytic nevi, consisting of a localized clustering of banal and atypical moles. We now report 4 more cases, confirming that the initial case was not an isolated finding. We examined the lesions clinically, with a dermoscope, with a Wood's light, and in 3 cases with UV photography so as to exclude nevus spilus from the differential diagnosis. The presence of an underlying dysplastic nevus syndrome phenotype in 4 of the 5 cases raises the possibility that agminated nevi arise as a consequence of postzygotic loss of heterozygosity and, thus, may represent a type 2 segmental manifestation of the atypical mole syndrome phenotype. Further studies of similar cases using microdissection techniques for analysis of loss of heterozygosity pattern are warranted.  相似文献   

11.
The expression of c-myc protein was studied in formalin-fixed, paraffin-embedded sections of 16 compound Spitz nevi (SNs), 20 ordinary compound melanocytic nevi (MNs) and 30 malignant melanomas (MMs), using monoclonal antibody 9E10 and an immunoperoxidase technique. Nine (56%) SNs, 16 (80%) MNs and 23 (77%) MMs showed positive reactions in some of the tumor cells (P = non-significant). The staining reactions were mostly cytoplasmic, and moderate to strong in intensity. The frequencies of positively stained cells were higher in the MN and SN groups. Most of the lesions with a significant dermal component did not show stratification of staining with progressive descent into the dermis. Therefore, the mode of expression of c-myc in routinely processed specimens does not differentiate between SNs, MNs and MMs. One possible reason is that the increased expression of the c-myc protein is not sufficient alone to promote proliferation and malignant transformation in these types of tumors.  相似文献   

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Background.  Exposure to ultraviolet (UV) radiation induces acute changes in common melanocytic naevi (CMN).
Aim.  To analyse changes in size and dermoscopic structures of CMN in healthy individuals under the influence of intense sun exposure and to investigate effectiveness of sunscreen usage in preventing the appearance of dermoscopic changes.
Methods.  The subjects were divided into an SS group and a non-SS group, according to whether they used sunscreen or not. Digital epiluminiscence microscopy (DELM) was performed before sun exposure and 28 days and 1 year after the cessation of intense sun exposure.
Results.  Eleven subjects with 60 naevi fulfilled the inclusion criteria. A significant increase in one diameter of the CMN was found 28 days after cessation of sun exposure, irrespective of sunscreen usage. There was no significant change in total dermoscopy score during the follow-up period in either the SS or non-SS group. There were definitive DELM changes at the 1-year follow-up in 10% of CMNs < 5 mm in size. Changes in pigmented network, globules and streaks were fully reversible in the remaining CMN. The use of sunscreen had no influence on these changes.
Conclusions.  The increases in the size of melanocytic naevi that we found 28 days after cessation of intense sun exposure are probably induced by UV radiation, whereas changes in DELM features that were not reversible in some small naevi at the 1-year follow-up could be related both to sun exposure and to the natural evolution of the naevi. The use of sunscreen does not seem to prevent these changes. Small naevi in low-risk young and middle-aged patients seem to be more prone to sun-induced DELM changes.  相似文献   

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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.  相似文献   

17.
IntroductionAtypical melanocytic nevi are acquired melanocytic lesions that were described for the first time by Clark in studies of melanocytic nevi in patients with melanomas. Today, the use of dermatoscopy has made identification of this type of nevus much easier.ObjectiveOur aim was to study the correlation between the clinical, dermatoscopic, and histopathologic findings of melanocytic nevi and compare our findings with those of previous studies. We also aimed to investigate the value of dermatoscopy for identifying atypical melanocytic nevi.Material and methodsIn this cross-sectional, observational study, 200 melanocytic lesions were analyzed in 166 patients examined between January 1, 2005 and December 31, 2005. We recorded the clinical, dermatoscopic, and histopathologic characteristics of each lesion and established the correlation between the different findings on a case-by-case basis. We then determined the agreement between diagnoses and assessed the value of dermatoscopy for identifying atypical melanocytic melanoma.ResultsThe clinical characteristics associated with atypical histology were a macular component (P < .001), irregular borders, and presence of 3 or more colors. Asymmetry, diameter greater than 5 or 6 mm, and progression were not associated with atypical histopathologic characteristics (P > .05). Agreement between clinical and histologic diagnosis was weak (κp = 0.38), whereas the agreement between dermatoscopic and histologic diagnosis was moderate (κp = 0.52). The area under the receiver operating characteristic curve for the model that included dermatoscopy was larger than that for the model that only included clinical data, and this difference was statistically significant.ConclusionsAtypical clinical features were not found to correspond to atypical histology. Dermatoscopy improved the accuracy of clinical diagnosis of atypical melanocytic nevus.  相似文献   

18.
BACKGROUND: Telomerase is a ribonucleoprotein DNA polymerase that is capable of synthesizing telomeres onto the ends of chromosomes. The cumulative loss of telomerase activity is believed to be associated with cell senescence. Telomerase activity has been shown to be higher in malignant melanomas than in common melanocytic nevi. The aim of the present study was to elucidate the pattern of expression of the human telomerase RNA (hTER) component in routinely processed specimens of Spitz nevi, malignant melanomas, and ordinary melanocytic nevi. METHODS: Ten specimens of each type of tumor were studied, using an in situ hybridization technique. RESULTS: All three types of tumors demonstrated moderate to high intensities of hTER expression, usually in more than half of the tumor cells, and the majority of the studied lesions in each group did not show stratification of staining. The hTER component was also detected in the epidermis, sweat glands, and pilosebaceous units. CONCLUSIONS: hTER levels do not necessarily correlate with the level of telomerase activity, and the level and pattern of hTER expression are not useful as an adjunct to the histologic differential diagnosis of Spitz nevi from melanocytic nevi and malignant melanomas.  相似文献   

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OBJECTIVE: To evaluate the utility of sequential imaging of melanocytic skin lesions. DESIGN: With the use of a computerized test environment, digital images of 80 melanocytic skin lesions (including 10 early melanomas) were presented to 24 dermatologists with different levels of experience in 3 sessions. The 3 sessions were designed to simulate the decision-making process (1) without the possibility of follow-up, (2) with the possibility of follow-up, and (3) after presentation of follow-up images. MAIN OUTCOME MEASURES: Diagnostic performance in terms of sensitivity, specificity, accuracy, treatment threshold, and utility. RESULTS: The possibility of follow-up increased the treatment threshold in all groups of dermatologists compared with decision making without the possibility of follow-up. The increase of the treatment threshold was accompanied by a loss of sensitivity and a gain in specificity. The overall diagnostic accuracy remained unchanged. After presentation of follow-up images, the diagnostic accuracy improved significantly. The sensitivity improved for all readers, but the specificity improved only for the most experienced readers. The utility of sequential imaging depended on the compliance of patients with follow-up. Under the assumption that all patients are compliant with follow-up, the utility of sequential imaging was superior to decision making without follow-up over a broad range of benefit-risk ratios. CONCLUSIONS: Sequential imaging of melanocytic skin lesions is a useful procedure for patients with multiple atypical nevi. Uncritical use of sequential imaging cannot be recommended, because the utility of this technique depends on the experience in the interpretation of follow-up images and on the patient's compliance with follow-up.  相似文献   

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