Factors Related to Thickness of Melanoma: Multifactorial Analysis of Variables Correlated with Thickness of Superficial Spreading Malignant Melanoma in Man

Computer analyses to identify correlations between thickness of primary superficial spreading malignant melanoma and eighteen variables previously reported to be related to prognosis were performed on a series of malignant melanomas. The variables that showed statistically significant (≤0.05) direct relationships to thickness were level (Clark), elevation of lesion, age of patient, least and greatest diameters of lesion, history of bleeding, ulceration, clinical and histologic stage, anatomic location, pedunculation, and satellitosis. The variables that did not correlate with thickness were clinical diagnosis of regional lymphadenopathy, in‐transit metastasis, duration of lesion, sex, history of a previous malignant melanoma, and history of a pre‐existing lesion at the site of the development of melanoma. Multiple regression analysis of the factors that showed statistically significant correlation with thickness of the primary lesion revealed a subset of six dominant variables that were most predictive of thickness, namely, level, elevation, largest diameter of lesion, ulceration, histologic stage, and age of the patient. 1981 American Society for Dermatologic Surgery, Inc.