Sunscreen Use and Melanocytic Nevi in Children: A Systematic Review

Abstract: We conducted a systematic review of the association between melanocytic nevi (MN) in childhood and sunscreen use. A bibliographic search was conducted between November 2008 and January 2009 using the following key words on MEDLINE and EMBASE: child*, in combination with naevi, nevi, naevus, nevus and sunscreen, sun protection. We also used Medical Subject Headings [sunscreening agents], or [radiation protection] with [nevus, pigmented]. A first screening was done on title and abstract reading. Randomized trials and cohort and cross‐sectional studies analyzing the relationship between the use of sunscreen and MN in children were selected. Three reviewers abstracted data from each article. The three sets of results were compared for concordance and rereviewed if necessary. Fifteen articles were included (20,743 children). The studies were not consistent in terms of the ages of the children, MN count methods, or sunscreen use assessment. Owing to this heterogeneity, we were unable to pool the studies and conduct a meta‐analysis. Twelve studies did not report that the use of sunscreen had a protective effect against MN development. Three studies reported a lower MN count when sunscreen was applied. This systematic review underlines the methodologic differences between studies. Eight of 15 studies reported a positive association between sunscreen application and MN count. Differences in MN counts, overexposure to sun, and inadequate sunscreen application on fair‐skinned children could explain the disparity in the results. There is still no evidence of a protective effect of sunscreen against MN development in children.     

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.     

Meyerson Phenomenon in Children: Observation in Five Cases of Congenital Melanocytic Nevi

Abstract:   To describe the characteristics of five pediatric patients with the Meyerson phenomenon associated with congenital melanocytic nevi, five cases were reviewed to retrieve information relating to clinical presentation, treatment and evolution of the eczematous phenomenon and of the nevi. Three of five patients were male. Mean age at presentation of the Meyerson phenomenon was 23 months (range: 4 mos–4 yrs). Three patients presented with only one halo eczematous lesion, while two patients presented with more then one halo eczematous lesions. The halo eczematous lesions were located on the leg, arm, and trunk in four, two, and two patients, respectively. All were associated with congenital melanocytic nevi with overlying hypertrichosis. Four were treated with topical corticosteroids, and five developed some degree of hypopigmentation within the nevic lesion. In children with Meyerson phenomenon associated with congenital hairy melanocytic nevi, neither trigger to the eczematous eruption nor preferential gender or anatomical site location was identified. The Meyerson phenomenon evolved towards hypopigmentation of the congenital melanocytic nevic lesions in all patients but no other cutaneous changes were observed on follow-up.     

The Relationship of Psoriasis and Melanocytic Nevi

Background:There is limited data about the relationship between psoriasis and melanocytic lesions and melanoma. Immunologic pathways which were implicated in psoriasis induce a reduction in the number of melanocytic nevi.Methods:We performed a prospective study in 100 psoriatic patients and 100 controls. Clinical data were recorded for all participants.Results:As compared with controls, patients had overall fewer nevi congenital nevi. Among psoriatic patients, biologic agents and disease severity did not correlate with the number of nevi.Conclusions:Psoriatic patients have fewer nevi than controls. Frequency of nevi in psoriatic patients is not related to treatment and disease severity.     

Histologic Features of Melanocytic Nevi in Older Patients

The histology of melanocytic nevi in elderly patients often differs from nevi in younger adults. Our hypothesis was that nevi in patients³ 60 yrs would demonstrate histologic patterns different from nevi in younger adults. Biopsies of nevi (n = 214) from 172 patients³ 60 yrs (mean age 69 ± 7 yrs) were examined by three dermatopathologists and a consensus diagnosis was rendered. Control specimens (n = 82) from 58 patients 20–40 yrs (mean age 31 ± 5 yrs) were evaluated. Compound melanocytic nevi were commoner in younger patients (37%) versus older patients (12%)(p < .0001). Junctional melanocytic nevi were more frequently diagnosed in older patients (10% versus 3%; p = .027) and a lentiginous, often heavily pigmented, growth pattern was common (12% of nevi) vs control group (3%; p = .028). Atypical ("dysplastic") nevi had a similar frequency at all ages, however 12/214 nevi in elderly patients (6%) exhibited marked atypia with features suggesting melanoma in‐situ. We conclude that benign junctional nevi are relatively common in elderly patients and that a lentiginous, heavily pigmented growth pattern, typically associated with younger patients, is often seen in both junctional and compound nevi in this older age group. This pattern must be differentiated from dysplastic nevus and melanoma in‐situ, which they may clinically resemble.     

Coexistence of Plaque-Type Blue Nevus and Congenital Melanocytic Nevi

A rare case of development of plaque-type blue nevus adjacent to congenital nevi in a 44-year-old woman is presented.     

Risk of Malignant Transformation of Congenital Melanocytic Nevi in Blacks

Abstract: The risk of small congenital melanocytic nevi (CMN) developing into melanoma is not known, but Is highly controversial. The frequency of small CMN is, paradoxically, slightly higher in some populations, such as blacks, who are at a lower risk of developing melanoma than whites. An estimate of the risk of malignant transformation of CMN in such a low-risk population could help In the management of congenital nevi in these patients and might also shed light on the inherent malignant fisk of small CMN. We used a national population-based cancer registry, the Surveillance, Epidemiology, and End Results program (SEER), and the incidence of CMN in blacks taken from published newborn surveys to calculate a risk of malignant transformation. We calculated a maximum risk using a model based on a worst-case scenario, assuming that all melanomas on glabrous skin arise in CMN. We also calculated a modified risk based on the known historical association of nevi and melanomas in blacks, and estimates of the histologic association of the two. The cumulative maximum risk of malignant transformation in blacks to age 75 years was 1 in 164. It was strongly age dependent, with the majority occurring in persons over age 45. The estimated maximum risk before age 15 was less than 1 in 10,000 CMN, and in blacks age 15 to 35 less than 1 in 3700 CMN. The modified risk suggests that the worst-case scenario overestimates the risk by at least a factor of 12, making the actual risk in blacks up to age 75 approximately 1 In 2000. Both the worst-case scenario model and the modified risk suggest a small to extremely small risk of malignant transformation, particularly before age 45. Although the specific morphology and circumstances of a particular CMN must be considered In decision making, we believe that routine prophylactic removal of small CMN in blacks is probably not warranted.     

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.     

BRAF V599E Mutation is Not Age Dependent: It is Present in Common Melanocytic Nevi in Both Children and Adults

Pigmented dermatofibrosarcoma protuberans (Bednar tumor) constitute 5–10% of all cases of dermatofibrosarcoma protuberans, and are usually considered mimics of melanocytic proliferations rather than fibrous lesions. We report two cases of pigmented fibrous proliferations that demonstrate features of both dermatofibromas and DFSP. The first case is a 19‐year‐old man with a three year history of a slowly growing pigmented lesion on the right arm. On clinical exam the lesion was a 7 mm firm pigmented papulonodular lesion. The second case is a 31‐year‐old woman with a 4–5 year history of a slowly enlarging, asymptomatic 'dark area' on the right buttock. On clinical exam the lesion is a 2 cm darkly pigmented flat nodule. Morphologically both lesions are primarily dermal proliferations of spindled cells admixed with pigmented dendritic melanocytes. The lesional cells trap collagen fibers at the periphery and there is basal cell hyperpigmentation. Adnexal structures are effaced but significant trapping of subcutaneous fat is not present. By immunohistochemistry both lesions show focal CD34 positivity but are negative for Factor XIIIa and melanocytic markers. Although overlap between dermatofibromas and DFSP is well documented in the literature, pigmented fibrous lesions with features of both entities are not well described.     

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.     

Expression of Phosphatase and Tensin Homologue,phospho-Akt,and p53 in Acral Benign and Malignant Melanocytic Neoplasms (Benign Nevi,Dysplastic Nevi,and Acral Melanomas)

BackgroundThe role of the phosphatidylinositol-3 kinase signaling pathway in the development of acral melanoma has recently gained evidence. Phosphatase and tensin homologue (PTEN), one of the key molecules in the pathway, acts as a tumor suppressor through either an Akt-dependent or Akt-independent pathway. Akt accelerates degradation of p53.ObjectiveWe assessed the expression of PTEN, phospho-Akt (p-Akt), and p53 by immunohistochemistry in benign acral nevi, acral dysplastic nevi, and acral melanomas in the radial growth phase and with a vertical growth component.MethodsTen specimens in each group were included. Paraffin-embedded specimens were immunostained with antibodies for PTEN, p-Akt, and p53. We scored both the staining intensity and the proportion of positive cells. The final score was calculated by multiplying the intensity score by the proportion score.ResultsAll specimens of benign acral nevi except one showed some degree of PTEN-negative cells. The numbers of p-Akt and p53-positive cells were higher in acral dysplastic nevi and melanoma than in benign nevi. P-Akt scores were 1.7, 1.8, 2.6, and 4.4, and p53 scores were 2.0, 2.1, 3.8, and 4.1 in each group. PTEN and p-Akt scores in advanced acral melanoma were higher than in the other neoplasms.ConclusionThe expression of PTEN was decreased and the expression of p-Akt was increased in acral melanoma, especially in advanced cases. The PTEN-induced pathway appears to affect the late stage of melanomagenesis. Altered expression of p-Akt is thought to be due to secondary changes following the loss of PTEN.     

Efficacy and Safety of 1,064 nm Q-switched Nd:YAG Laser Treatment for Removing Melanocytic Nevi

Background

Until recently, the removal of melanocytic nevi has been performed with a CO₂ laser or Er:YAG laser. These lasers have been useful for removing affected spots. However, enlargement of spots or some sequelae, including depressed or hypertrophic scars, could develop as unwanted results. The Q-switched Nd:YAG laser has been used to remove deep-seated melanocytes, such as Ota nevus or tattoos. However, there have been no previous experiments performed to test the efficacy and safety of this laser treatment for melanocytic nevi.

Objective

The objective of this study was to investigate the efficacy and safety of the 1,064 nm Q-switched Nd:YAG laser for removing melanocytic nevi, including congenital nevomelanocytic and acquired nevomelanocytic nevi.

Methods

Two thousand and sixty four Korean patients with small melanocytic nevi were treated with a Q-switched Nd:YAG laser from 2005 to 2009. High-resolution photographs were taken in identical lighting and positions before and after the six weeks of treatment to observe the procedural efficacy.

Results

About 70% of the nevi treated using a 1,064 nm Q-switched Nd:YAG laser were completely removed after one session. The other 30% were completely treated within three sessions. The appearance of sequelae such as hollow scars noticeably decreased compared to the results seen in CO₂ or Er:YAG laser treatments.

Conclusion

Use of the 1,064 nm Q-switched Nd:YAG laser is a safe and effective treatment modality for melanocytic nevi.