The prognostic implications of microscopic satellites in patients with clinical stage I melanoma.

Controversy exists as to whether microscopic satellites influence prognosis or patterns of progressive disease in patients with clinical stage I melanoma. Fifty patients with clinical stage I melanoma and microscopic satellites were prospectively studied from 1972 to 1984. To allow for complete histopathology assessment, 30 patients with microscopic satellites who were prospectively seen from 1972 to 1979 were matched to a cohort of 77 patients with vertical growth-phase melanoma without microscopic satellites according to six attributes. The matched cohort study showed that the presence of microscopic satellites appeared to be associated with increased local regional cutaneous and regional nodal disease and a significantly decreased actuarial disease-free survival. A Cox multivariate regression analysis that involved 384 patients with vertical growth-phase clinical stage I melanoma showed that the presence of microscopic satellites independently predicted a poorer disease-free survival and overall survival. Therefore, this study demonstrated that the presence of microscopic satellites correlated with a significantly decreased survival.