Letrozole and Goserelin or Leuprolide in Treating Premenopausal Estrogen Receptor-Positive Patients With Stage IV Breast Cancer

RATIONALE: Aromatase inhibitors, such as letrozole, prevent the formation of estradiol, a female hormone. Giving letrozole together with goserelin, leuprolide, or surgery may be an effective treatment in women with hormone-dependent breast cancer. PURPOSE: This phase II trial is studying how well giving letrozole together with goserelin or leuprolide works in treating premenopausal estrogen receptor-positive patients with stage IV breast cancer.