Measurement of Aromatisation by a Urine Technique Suitable for the Evaluation of Aromatase Inhibitors in Vivo

Abstract

By modification of a recently developed method for separation of radio-labelled urinary oestrogens we were able to separate oestrogen metabolites and measure their isotope ratios in urine following injections of [³H]Δ⁴-androstenedione and [¹⁴C]oestrone. This method provides a useful tool for studying in vivo aromatisation of Δ⁴-androstenedione into oestrone in breast cancer patients before and during treatment with aromatase inhibitors.