How rapidly do oncologists respond to clinical trial data?

In the era of evidence-based medicine, convincing clinical trial data should influence clinical practice if disseminated in an appropriate manner. Here we discuss the influence of clinical trial results from the Arimidex, Tamoxifen Alone or in Combination trial on the usage of tamoxifen and anastrozole in the treatment of postmenopausal women with hormone receptor-positive early breast cancer. Data were derived from structured interviews with practicing medical oncologists over a period of 28 months. The overall use of hormonal therapy was high and increasing over the period studied. Significant increases in the use of anastrozole as adjuvant hormonal therapy were accompanied by significant decreases in the use of tamoxifen. This culminated in the use of anastrozole surpassing tamoxifen use by the end of the study period, accounting for over 50% of hormonal therapy use for postmenopausal early breast cancer. This study suggests that the dissemination of key clinical data, accompanied by professional commentary and regulatory actions, can rapidly influence the clinical practice of medical oncologists.