Five Years of Exemestane as Initial Therapy Compared to 5 Years of Tamoxifen Followed by Exemestane: The TEAM Trial, a Prospective, Randomized, Phase III Trial in Postmenopausal Women with Hormone-Sensitive Early Breast Cancer.

Abstract

Abstract Background: Exemestane (E) is a steroidal aromatase inhibitor (AI) with an established role in early breast cancer after 2–3 years of tamoxifen (T). Additionally, AIs have shown superiority to T as initial adjuvant therapy. The Tamoxifen Exemestane Adjuvant Multinational (TEAM) study has been prospectively designed to compare the role of E as initial adjuvant therapy with a sequential approach of T followed by E (T→E).Methods: Postmenopausal patients with hormone receptor–positive early breast cancer were randomized to open-label E 25 mg/d or T 20 mg/d. All patients completed surgery and chemotherapy, if indicated. Data were collected and analyzed by the Central Data Center in Leiden, The Netherlands. The trial was initiated in 2001 with the primary objective being a comparison of disease-free survival (DFS) with T vs E. In 2004, TEAM was modified in response to new data; all those initially receiving T were switched to E after 2.5–3 years. An additional 2500 patients were recruited and randomized at diagnosis to E or T→E for 5 years. The modified study design includes 2 coprimary endpoints: (1) DFS of T vs E that was previously reported at 2.75 years median follow-up (Jones S et al, abstract #15 presented at SABCS 2008); and (2) DFS at 5 years of E vs T→E that will be the focus of results presented here.Results: Between 2001 and January 2006, 9775 women were randomized to TEAM. In total, 99% of patients were ER+ and/or PgR+, 50% were node-negative, 44% underwent mastectomy, 68% received radiotherapy, and 36% received chemotherapy. In September 2009, median follow-up will be 5.5 years and the protocol-specified 1285 overall DFS events (locoregional or distant recurrence, second breast cancers, or death without recurrence) will have occurred, allowing for analysis of the second coprimary endpoint. We will present a detailed analysis of the 5-year results from theTEAM trial, the only prospectively powered randomized trial to compare 5 years of an initial AI vs T→AI, 2 commonly received adjuvant therapies for women with hormone receptor–positive early breast cancer. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 11.