Clinical Features of Malignant Melanoma of the Skin <i>Versus</i> Suspicious Benign Skin Lesions

<h3>Background/Aim:</h3> The aim of this study was to ascertain the clinical features that facilitate the differentiation of malignant melanoma of the skin (MM) from suspicious benign skin lesions (SBSLs). <h3>Patients and Methods:</h3> From December 2021 to February 2026, a database of 126 excised skin lesions (ESLs) was generated including 106 cases of SBSLs, 13 of non-nodular melanomas (NNMs), and seven of nodular melanomas (NMs). The ESLs were evaluated according to the ABCDE criteria, the 7-PCL scale, and other clinical signs of suspected MM, such as the ugly duckling sign. <h3>Results:</h3> Fisher’s exact test, revealed that, in comparison to SBSLs, all MM cases exhibited a higher propensity for evolution in size, shape or color within six months (<i>p</i>&lt;0.001), firm to touch (<i>p</i>=0.002), rapid growth within six weeks/atypical skin lesion <i>de novo</i> (<i>p</i>&lt;0.001), inflammation (<i>p</i>=0.034), oozing or crusting (<i>p</i>=0.004), and sensory changes including itching (<i>p</i>=0.023). In Firth’s penalized logistic regression, for NNMs alone, no clinical feature exhibited a statistically significant higher frequency compared to SBSLs. In multivariate analysis, rapid growth within six weeks/atypical skin lesion <i>de novo</i> was the only clinical feature statistically more frequent in NMs alone than SBSLs [odds ratio (OR)=14.71, 95% confidence interval (CI)=1.02-2583, <i>p</i>=0.049] and in all MM cases compared to SBSLs (OR=4.83, 95%CI=1.04-27.29, <i>p</i>=0.045). <h3>Conclusion:</h3> Rapid lesion growth within six weeks/atypical skin lesion de novo represents the primary independent clinical feature distinguishing MM from SBSLs. Conversely, standard structural metrics like a diameter greater than 6 mm fail to provide a statistically reliable differentiation between MM and SBSLs during initial clinical inspection in multivariate analysis.