Clinical Features of Malignant Melanoma of the Skin Versus Suspicious Benign Skin Lesions

Background/Aim: 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). Patients and Methods: 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. Results: 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 (p<0.001), firm to touch (p=0.002), rapid growth within six weeks/atypical skin lesion de novo (p<0.001), inflammation (p=0.034), oozing or crusting (p=0.004), and sensory changes including itching (p=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 de novo 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, p=0.049] and in all MM cases compared to SBSLs (OR=4.83, 95%CI=1.04-27.29, p=0.045). Conclusion: 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.