Prognosis of thick cutaneous melanoma

Ten percent of all patients with melanoma present with thick primary tumors (> or = 4 mm or Clark level V). To determine factors associated with outcomes, we performed a retrospective analysis of 120 patients who had definitive primary treatment of their thick cutaneous melanomas at Memorial Sloan-Kettering Cancer Center between January 1986 and April 1995.

Data were collected via chart review and patient interview. Association between factors was determined by chi-square analysis. Survival analysis was performed by the method of Kaplan and Meier. Univariate analysis by log-rank testing and multivariate analysis using the Cox regression model were used to identify factors associated with disease-free and overall survival.

Median age was 61 years (range 19 to 87 years). There were 80 males and 40 females. Median Breslow thickness was 6 mm (range 1.8 to 25.0 mm). Ninety-three patients (78%) underwent lymphadenectomy (52 elective and 41 therapeutic). Twenty-one percent (11 of 52) of the elective dissections were positive. Median followup was 3.8 years (5.2 years for patients no evident disease and 2.0 years for those dead of disease). Overall survival for the entire group was 62% at 5 years and 43% at 10 years. Age, gender, and anatomic site (axial versus extremity) were not factors predictive of overall survival. Increasing thickness, nodal status at presentation (American Joint Commission on Cancer stage II versus III), and the presence of ulceration were significant predictors of both disease relapse and disease-specific mortality in both univariate and multivariate analyses. There was no difference in postrelapse survival between patients suffering local, nodal, or distant relapse (p = 0.63).

Patients presenting with thick cutaneous melanomas are expected to have more than 50% 5-year survival, and they should not be denied the opportunity for aggressive locoregional management. Thickness, positive nodal status, and ulceration are associated with a higher mortality rate. The fact that patients with local or nodal recurrences fare as poorly as those with overt distant metastases implies that the former events are predictors of subclinical systemic disease.