Is the oncotype DX test useful in elderly breast cancer patients: a subgroup analysis of real-life Italian PONDx study.

Abstract

The 21-gene Oncotype DX Breast Recurrence Score® test, (Genomic Health, Redwood City CA) has not been formally evaluated in an older cohort with estrogen receptor (ER)-positive breast cancer (BC) in term of physicians' treatment decisions. We determine the utility of Recurrence Score® (RS) result on adjuvant therapy prescription in elderly patients with resected early BC. PONDx was a multicenter, prospective, observational study, and which investigated the real-life use of the Oncotype DX® test by physicians treating early BC patients in clinical practice. Data from the elderly extracted from 1724 BC patients who underwent Oncotype DX testing were available from 27 reference centers located in 6 regions of Italy (Lombardia, Lazio, Emilia Romagna, Campania, Abruzzo, and Marche). A total of 230 patients (13% of the total population) aged > 70years were analyzed. The study primarily evaluated the impact of the Oncotype DX test on adjuvant treatment decisions. Physicians chosen chemotherapy plus endocrine therapy in 36% of elderly patients and 46% of those 50-70years before the Oncotype DX test. After knowing the RS data, these rates fell to 23 and 33% (38 and 28% relative reduction, respectively). 21-gene test may be helpful even in a relatively low-risk group as elderly patients and may avoid the toxicity of adjuvant chemotherapy in a significant amount. If the Oncotype DX test is currently adopted on a large scale among the elderly and may impact the general prognosis of elderly BC patients, it is challenging and still unproven.