Figure 2
From: Deficits in plasma oestradiol measurement in studies and management of breast cancer
Each panel shows the results of analysing pairs of samples from 10 postmenopausal breast cancer patients. Light column, measured serum oestradiol before treatment (Pre); dark column, result during the use of the aromatase inhibitor, anastrozole. (a), (b) Results obtained when the oestradiol was measured by direct assay: (a) Beckman Coulter Access Immumoassay system Estradiol 33540, and (b) DSL 3rd Generation Estradiol Radioimmunoassay DSL-39100. (c), (d) Results when the oestradiol is measured after a pre-extraction with an organic solvent: (c) extraction and radioimmunoassay (as used at the Royal Marsden [6]), and (d) the DSL-39100 kit after pre-extraction of serum samples with diethyl ether. Arrows indicate the detection limits for the assays; no arrow in (d) since this analysis was performed for the present study only and no detection limit was determined.