Consistent with what has been reported in the United States, use of the Oncotype DX® breast cancer test influenced treatment decisions for early-stage breast cancer patients in Spain. These results were presented at the 35th European Society for Medical Oncology (ESMO) Congress.
The Oncotype DX breast cancer test measures the expression of 21 genes in a sample of a breast tumor. The test generates a Recurrence Score® that provides information about the likelihood of cancer recurrence and the likelihood of chemotherapy benefit in women with early-stage breast cancer.
Studies of U.S. physicians and patients have indicated that use of the Oncotype DX breast cancer test can influence breast cancer treatment decisions. Test results may, for example, change the treatment recommendation from chemotherapy plus hormonal therapy to hormonal therapy alone (or vice versa).
To explore use of the test outside of the U.S., researchers conducted a study among 107 breast cancer cases diagnosed and treated in Spain. Information about adjuvant treatment plan was collected before and after obtaining the Oncotype DX Recurrence Score.
- Knowledge of a patient’s Recurrence Score changed the oncologists’ treatment recommendations in 32% of the cases: in 21% of the cases, the treatment plan switched from chemotherapy plus hormonal therapy to hormonal therapy alone. In 11% of the cases, the treatment plan switched from hormonal therapy alone to chemotherapy plus hormonal therapy.
- The study also assessed how use of the test affected a physician’s confidence in his or her treatment plan. In 61% of the cases, oncologists reported increased confidence in their treatment decisions, and in 7% of cases the oncologists reported decreased confidence.
Similar to what has been reported in the United States, these results from Spain indicate that the Oncotype DX breast cancer test influenced adjuvant therapy decisions for women with early breast cancer.
 Lo SS, Mumby PB, Norton J et al. Prospective multicenter study of the impact of the 21-gene recurrence score assay on medical oncologist and patient adjuvant breast cancer treatment selection. Journal of Clinical Oncology. 2010; 28:1671-1676.
 Albanell J, Colomer R, Ruiz-Borrego M et al. Prospective transGEICAM study of Oncotype DX® in clinical decision making in estrogen receptor-positive node-negative breast cancer women. Presented at the 35th European Society for Medical Oncology (ESMO) Congress, Milan, Italy, October 8-12, 2010. Abstract 222PD.