Albumin-bound and non-protein-bound oestradiol and testosterone in postmenopausal breast disease.

Several studies have recently reported the percentage of non-protein-bound (NPB) oestradiol (E2) to be higher in patients with breast cancer than in normal controls. Using postmenopausal volunteers, we have examined the fractional binding of E2 and testosterone (T), as well as total E2 and T, sex-hormone binding globulin (SHBG), luteinising hormone (LH) and follicle stimulating hormone (FSH), in normal women, those at risk of developing breast cancer and women with breast cancer at first diagnosis and first recurrence. No significant differences were observed in either the concentration or in the percentage of NPB E2 or T, or in any of the other hormones measured. The validity of our observations were confirmed by expected relationships between E2, T, SHBG and body mass.