This phase II trial compares leuprolide to goserelin for reducing estrogen production by the ovaries in pre- or peri-menopausal women with breast cancer. Estrogen can cause the growth of breast cancer cells. Both leuprolide and goserelin lower the amount of estrogen made by the body. This may help stop the growth of tumor cells that need estrogen to grow. This study compares lower dose leuprolide, higher dose leuprolide, and goserelin for their ability to suppress the function of the ovaries to produce estrogen. Both doses of leuprolide may be as safe, tolerable and/or effective as goserelin in suppressing ovarian function in pre- or peri-menopausal women with breast cancer.
Female subject aged ≥ 18 years
Pre- or peri-menopausal patient, who had (1) menses either within the 12 months prior to or since breast cancer diagnosis or (2) estradiol concentration above the postmenopausal range per institutional laboratory guidance either within the 12 months prior to or since breast cancer diagnosis.
Planning to take GnRHa therapy in combination with oral endocrine therapy (tamoxifen, anastrozole, exemestane, or letrozole) for adjuvant treatment of stage 1-3 breast cancer or for treatment of metastatic breast cancer. Prior treatment with GnRHa therapy for treatment of non-oncologic conditions or during chemotherapy is permitted.
Not planning bilateral salpingo-oophorectomy during the 6-month study duration
Prior bilateral salpingo-oophorectomy
Known to be pregnant or breastfeeding (negative pregnancy test will be confirmed prior to study treatment initiation)
Concomitant use of systemic or transdermal estrogen products
Known allergy or hypersensitivity to goserelin or leuprolide, or any of the excipients in the medications