Estrogen receptor in malignant melanoma.

The significance of an estrogen binding protein (ER) in malignant melanoma remains controversial. We have prospectively assayed for ER on 141 patients with malignant melanoma and correlated the presence of the ER with known prognostic variables. The overall incidence of ER was 43%. The incidence of ER in males was 38.7% and 50% in females (not significant). There is an increased incidence of ER+ melanoma in women with extremity lesions (P = .08). The disease-free interval (DFI), survival, and recurrent interval were 42.0 +/- 4.0, 52.3 +/- 4.3, 13.7 +/- 1.7 months in ER- patients; 63.7 +/- 11.6, 76.1 +/- 11.4, 26.5 +/- 7.3 months in ER+ patients (1 to 10 fmol/mg cytosol protein), and 69.8 +/- 17.9, 102.7 +/- 27.9, 29.4 +/- 9.9 months in ER+ patients (greater than 10 fmol/mg cytosol); respectively. When ER+ groups were combined, the DFI in women with ER+ lesions was significantly longer than those with ER- tumors (P less than .05). Cox multivariate analysis demonstrated that ER status is a significant variable of survival along with thickness level and nodal status. These observations suggest that ER may be a marker for a more biologically indolent melanoma.