Individuals with melanocortin 1 receptor (MC1R) gene variants have been shown to carry an increased risk for the development of melanoma. In this study, we investigated the relationship of MC1R gene variants and the risk of melanoma in 123 melanoma patients and 155 control subjects from Greece. The entire MC1R gene was sequenced for polymorphisms and the results were correlated with host factors and pigmentary characteristics. MC1R polymorphisms were present in 59.4% of melanoma patients compared to 37.5% of controls, yielding an odds ratio (OR) of 2.43 (95% confidence interval (CI) = 1.50-3.96, P < 0.001) for melanoma among MC1R carriers. The risk of melanoma was enhanced in individuals carrying multiple variant alleles (OR = 6.97; 95% CI = 1.86-26.12, P = 0.004). Only the Val60Leu, Arg142His, and Arg151Cys variants were significantly associated with melanoma risk. In stratified analysis, the risk of melanoma among MC1R carriers was not influenced by skin phototype, skin color, or hair color. No association was found between MC1R genotype and the age of onset of melanoma, the tumor location, or the tumor thickness. In conclusion, MC1R polymorphisms are a predisposing factor of melanoma in a southern European population with a relatively low incidence of the disease.

Intermittent sun exposure of moderate intensity during childhood/adolescence and outdoor leisural activities, in conjunction with a more resistant skin phenotype to acute sunburns and a strong association with nevi and solar lentigenes was a prominent determinant of melanoma risk in our population.

Background Nodular melanoma (NM) is more likely to be fatal compared with other melanoma subtypes, an effect attributed to its greater Breslow thickness. Methods Clinicopathological features of NM and superficial spreading melanoma (SSM) diagnosed in 17 centers in Europe (n = 15), the United States, and Australia between 2006 and 2015, were analyzed by multivariable logistic regression analysis, with emphasis on thin (T1 ≤ 1.0 mm) melanomas. Cox analysis assessed melanoma-specific survival. All statistical tests were two sided. Results In all, 20 132 melanomas (NM: 5062, SSM: 15 070) were included. Compared with T1 SSM, T1 NM was less likely to have regression (odds ratio [OR] = 0.46, 95% confidence interval [CI] = 0.29 to 0.72) or nevus remnants histologically (OR = 0.60, 95% CI = 0.42 to 0.85), and more likely to have mitoses (OR = 1.97, 95% CI = 1.33 to 2.93) and regional metastasis (OR = 1.77, 95% CI = 1.02 to 3.05). T1 NM had a higher mitotic rate than T1 SSM (adjusted geometric mean = 2.2, 95% CI = 1.9 to 2.5 vs 1.6, 95% CI = 1.5 to 1.7 per mm2, P &lt; .001). Cox multivariable analysis showed a higher risk for melanoma-specific death for NM compared with SSM for T1 (HR = 2.10, 95% CI = 1.24 to 3.56) and T2 melanomas (HR = 1.30, 95% CI = 1.01 to 1.68), and after accounting for center heterogeneity, the difference was statistically significant only for T1 (HR = 2.20, 95% CI = 1.28 to 3.78). The NM subtype did not confer increased risk within each stratum (among localized tumors or cases with regional metastasis). Conclusions T1 NM (compared with T1 SSM) was associated with a constellation of aggressive characteristics that may confer a worse prognosis. Our results indicate NM is a high-risk melanoma subtype that should be considered for inclusion in future prognostic classifications of melanoma.