Estrogen and progesterone receptors and tamoxifen in malignant melanoma.

Tumor biopsies from 68 patients with malignant melanoma were assessed for estrogen receptor (ERc) binding, and 32 of these for progesterone receptor (PRc) binding. Twenty-five patients (37%) had ERc greater than or equal to 5 fmols/mg protein; 14 patients (44%) had PRc greater than or equal to 10 fmols/mg of protein. There was no significant difference between the sexes in relation to the presence or absence of ERc or PRc. The tumor ERc and PRc levels did not predict the survival of these patients. Seventeen patients were treated with tamoxifen; three female patients had objective responses. Two of the patients with complete response had ERc levels of 4.3 and 19 fmols/mg tumor cytosol protein, while the third patient had no detectable ERc.