S1207 Hormone Therapy With or Without Everolimus in Treating Patients With Breast Cancer

RATIONALE: Estrogen can cause the growth of breast cancer cells. Hormone therapy using tamoxifen citrate, goserelin acetate, leuprolide acetate, anastrozole, letrozole, or exemestane, may fight breast cancer by lowering the amount of estrogen the body makes. Everolimus may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. It is not yet know whether hormone therapy is more effective when given with or without everolimus in treating breast cancer. PURPOSE: This randomized phase III trial studies how well giving hormone therapy together with or without everolimus work in treating patients with breast cancer.

OBJECTIVES: Primary * To compare whether the addition of one year of everolimus (10 mg daily) to standard adjuvant endocrine therapy improves invasive disease-free survival (IDFS) in patients with high-risk, hormone-receptor (HR)-positive, and human epidermal growth factor receptor (HER)2-negative breast cancer. Secondary * To compare whether the addition of one year of everolimus to standard adjuvant endocrine therapy improves overall survival (OS) and distant recurrence-free survival (DRFS) in this patient population. * To evaluate the safety, toxicities, and tolerability of one year of everolimus in combination with standard adjuvant endocrine therapy and to compare it with standard adjuvant endocrine therapy plus placebo in this patient population. * To determine whether the benefit of one year of everolimus use in addition to standard adjuvant endocrine therapy varies by recurrence score (RS), nodal status, or other commonly used prognostic factors. * To evaluate adherence to 1-year treatment of everolimus in comparison to placebo in addition to standard adjuvant endocrine therapy in this patient population. * To collect specimens in order to evaluate biomarkers of therapeutic efficacy. (exploratory) OUTLINE: This is a multicenter study. Patients are stratified according to risk level (node-negative and recurrence score \[RS\] \> 25 in the primary tumor, and a tumor measuring ≥ 2 cm in greatest diameter treated with adjuvant therapy vs 1-3 positive lymph nodes and RS \> 25 treated with adjuvant therapy vs ≥ 4 positive lymph nodes \[any RS value\] treated with adjuvant therapy vs ≥ 4 positive lymph nodes \[any RS value\] prior to or after neoadjuvant chemotherapy). Patients are randomized to 1 of 2 treatment arms. * Arm I: Patients receive an approved endocrine therapy comprising tamoxifen citrate\*, goserelin acetate\*\* or leuprolide acetate\*\*, or aromatase inhibitor (anastrozole, letrozole, or exemestane) for 2-5 years. Patients also receive a placebo orally (PO) daily for 1 year in the absence of disease progression or unacceptable toxicity. * Arm II: Patients receive an approved endocrine therapy regimen as in arm I. Patients also receive everolimus PO daily for 1 year in the absence of disease progression or unacceptable toxicity. NOTE: \*Men receive tamoxifen citrate PO for 5 years. NOTE: \*\*Goserelin acetate or leuprolide acetate is given if patient is or becomes postmenopausal. Blood and tissue samples are collected for biomarker studies. After completion of study treatment, patients are followed up every 6 months for 2 years and then yearly thereafter for 10 years.