Differences in individual and environmental factors between cutaneous melanoma and atypical Spitz tumour in children and adolescents.

It is not known if children and adolescents with atypical Spitz tumour and cutaneous melanoma differ in terms of etiological factors. The aim of this study was to explain differences in individual and environmental factors between cutaneous melanoma and atypical Spitz tumour. In the context of a study on melanocytic lesions, all subjects aged under 20 years with either cutaneous melanoma or atypical Spitz tumour were included (N = 105). Information on socio-demographic characteristics, individual and environmental factors were collected for both mother and child. The Fisher's exact test and the Mann-Whitney U test were used for categorical variables and continuous variables respectively. A multivariate logistic model was used to explain differences in outcome by differences in explanatory variables. In comparison to patients with cutaneous melanoma, patients with atypical Spitz tumour had less freckles (p = 0.020), lower number of common nevi (p = 0.002), and lower body mass index (p = 0.001) and experienced less sunburns episodes (p = 0.008). However, in the multivariate analysis, only a low number of common nevi remained statistically significant. Children and adolescents with cutaneous melanoma have a high number of nevi in comparison to the same-age group with atypical Spitz tumour.Conclusion: The results of this study suggest that the only difference in individual and environmental risk factors between cutaneous melanoma and atypical Spitz tumour in children and adolescents is the number of nevi. What is Known: •Atypical Spitz tumours and cutaneous melanoma in children and adolescents are clinically similar, but compared with melanoma, they have a good overall prognosis. •Risk factors for cutaneous melanoma in children and adolescents are similar to the ones found in adults in the literature What is New: •Differences in individual and environmental risk factors for atypical Spitz tumour in children and adolescents are described for the first time in this study. •Individual and environmental factors for atypical Spitz tumour in children and adolescents are comparable to cutaneous melanoma, except for the presence of low number of nevi.

Chronically sun-damaged melanomas express low levels of nuclear glutathione-S-transferase-π: an epidemiological and clinicopathological study in Italy.

The detoxifying enzyme glutathione-s-transferase pi (GST-π) is present in keratinocytes and melanocytes and exerts a protective role against tumour progression. Melanomas close to melanocytic naevus remnants occur less frequently on sun-exposed areas, whereas solar dermal elastosis, hallmark of chronic sun-damage, characterise melanomas on sun-exposed skin. We evaluated the expression of GST-π in 113 melanomas associated to melanocytic naevus remnants or to solar dermal elastosis, classified according to clinical characteristics, history of sun exposure, histological subtypes and AJCC staging. Chronically sun-damaged melanomas, identified by moderate-severe solar dermal elastosis, showed a lower nuclear GST-π expression and a higher thickness than those related to melanocytic naevus remnants (p < 0.03). Multivariate logistic regression analysis demonstrated that male gender and chronic sun-exposure are independent risk factors significantly associated to melanomas localised on the trunk (OR = 3.36, 95% CI: 1.31-8.65; OR = 5.97, 95% CI: 1.71-20.87). If confirmed on a larger series, lower expression of nuclear GST-π in melanoma cells could represent a possible marker of chronically sun-damaged melanoma pathogenesis.

Sequential molecular analysis of circulating MCAM/MUC18 expression: a promising disease biomarker related to clinical outcome in melanoma.

MCAM/MUC18 is a cell adhesion molecule associated with higher incidence of relapse in melanoma. The purpose of our study was to evaluate its role as a promising disease biomarker of progression through sequential molecular MCAM/MUC18 RT-PCR assay on serial blood samples collected during the clinical follow-up of 175 melanoma patients in different American Joint Committee on Cancer (AJCC) stages. MCAM/MUC18 molecular detection, found at least once in 22 out of the 175 patients, was significantly associated with poor prognosis and death (p < 0.001), regardless of the AJCC stages. Positive expression, either if primarily present or later acquired, was associated with melanoma progression, whereas patients primarily negative or with subsequent loss gained clinical remission or stable disease, even if in advanced stages (p < 0.005). Six AJCC advanced stages always MCAM/MUC18 negative are in complete remission or with a stable disease (p < 0.007). Semiquantitative immunohistochemical MCAM/MUC18 staining on corresponding primary melanomas was related to peripheral molecular expression. Correlations between circulating molecular and tissutal immunohistochemical detection, primary tumour thickness, AJCC stages and clinical outcome were statistically evaluated using Student's t test, ANOVA, Spearman's rank correlation test, Pearson χ (2)-test and McNemar's test. In our investigation, MCAM/MUC18 expression behaves as a "molecular warning of progression" even in early AJCC patients otherwise in disease-free conditions. Achievement of this molecule predicted the emergence of a clinically apparent status, whereas absence or persistent loss was related to a stable disease or to a disease-free status. If confirmed in larger case series, MCAM/MUC18 molecular expression could predict good or poor clinical outcome, possibly becoming a promising prognostic factor.