The presence of estradiol and progesterone receptors (ER and PR, respectively) was assessed in 24 removed cutaneous melanomas, adapting the routine procedure used for the detection of the presence of these steroid hormone receptors in breast cancers. The study included only those cases which were not subjected to any anticancer therapy before surgery. The ER and PR values were comparable to those found in breast cancer and the tumors thus investigated could be classified in the same four distinct groups, namely ER+PR+, ER+PR-, ER-PR+, and ER-PR-. Each group is expected to exhibit a specific rate of response to endocrine therapy. No relation was found between the presence of steroid receptors and the type of tumor tissues (benign and primary tumors, recurrences or metastases), or the sex of the patients. Because of the small number of cases in each age group we could not correlate the levels of ER+ and PR+ with the age of the patients. Saturation analysis, competition studies and Scatchard analysis were performed in order to determine the characteristics of ER. Our data suggest that cutaneous melanoma cytosols contain a saturable, high affinity and low capacity, specific binding component for estradiol. Further investigations are required to show that estrogen responsive tissues are functional in either melanocytes or melanomas from any species.