Safety of Toremifene and Tamoxifen Therapy in Premenopausal Patients With Operable Breast Cancer

Inclusion criteria

• Women aged ≥18 years, premenopausal
• Histologically confirmed invasive breast cancer by core needle biopsy, hormonal receptor positive, defined as estrogen receptor(ER)/progesterone receptor(PR) positive
• Patients must have received standard local therapy: normalized modified radical mastectomy or breast conserving surgery with negative margin and post-surgical radiotherapy. Patient should completed adjuvant therapy according to conditions, including adjuvant radiotherapy, neoadjuvant or adjuvant chemotherapy.
• Leukocyte ≥ 3*109/L; Platelets ≥ 75*109/L; Serum glutamate oxaloacetate(AST/SGOT) or serum glutamic-pyruvic transaminase(ALT/SGPT) <2.5 times of upper limit of normal (UNL) range Serum creatinine/blood urea nitrogen(BUN) ≤ upper limit of normal (UNL) range; Written informed consent according to the local ethics committee requirements.
• Has Eastern Cooperative Oncology Group(ECOG) Performance Score 0-2;

Exclusion criteria

• Histologically confirmed hormonal receptor negative.
• Have received neoadjuvant/adjuvant endocrine therapy.
• With metastatic tumor.
• Family history of endometrial cancer or ovarian cancer or any other kind of gynecological malignant tumor.
• Have already been detected of ovarian abnormality or endometrial thickening by transvaginal ultrasound.
• With any of complications that will increase sex hormone level: pituitary adenoma，ovarian tumor, thymic cancer，etc.
• With any of complications that will decrease sex hormone level:hyperthyroidism，hypothyroidism，liver cirrhosis，severe malnutrition，Turner's syndrome，sex hormone synthetase deficiency, intracranial tumor, pituitary atrophy, etc.
• Ovarian ablation or suppression
• With severe non-malignant co-morbidity that will influence long-term follow up.
• With severe hepatic dysfunction, Child-Pugh C.
• With severe cardiac dysfunction, New York Heart Association (NYHA) grading III or worse.
• Known severe hypersensitivity to any drugs in this study;