Hormone Replacement Therapy in Relieving Menopausal Symptoms in Postmenopausal Women With Previous Stage I or Stage II Breast Cancer

DISEASE CHARACTERISTICS: Prior diagnosis of stage I or II breast cancer No clinical evidence of recurrence Meets criteria for 1 of the following: Amenorrheic for at least the past 6 months Radiotherapy- or chemically-induced ovarian suppression allowed Prior surgical bilateral oophorectomy Experiencing vasomotor symptoms (i.e., hot flashes or night sweats) with or without vaginal dryness No undiagnosed postmenopausal bleeding No ductal carcinoma in situ or lobular carcinoma in situ alone Hormone receptor status: Not specified PATIENT CHARACTERISTICS: Age Postmenopausal Sex Female Menopausal status Postmenopausal Performance status Not specified Life expectancy Not specified Hematopoietic Not specified Hepatic No severe, active liver disease with abnormal liver function tests No acute, intermittent porphyria Fibrinolysis and coagulation normal Renal Not specified Cardiovascular No prior deep vein thrombosis Thrombophlebitis or superficial phlebitis alone allowed No prior retinal vein thrombosis Pulmonary No prior pulmonary embolism Other Not pregnant No prior alcohol, drug, or chemical abuse No other prior or concurrent malignancy except nonmelanoma skin cancer or carcinoma in situ of the cervix PRIOR CONCURRENT THERAPY: Biologic therapy Not specified Chemotherapy No concurrent chemotherapy Endocrine therapy More than 3 months since prior oral or transdermal hormone replacement therapy (HRT) More than 5 years since prior HRT implant No other concurrent HRT No concurrent gonadotropin-releasing hormone agonists (e.g., goserelin) if less than 2 years of planned treatment remains No other concurrent low-dose progestins No concurrent tibolone No concurrent phytoestrogens (e.g., black cohosh, red clover, or soy) Radiotherapy See Disease Characteristics Surgery See Disease Characteristics Other No concurrent Hypericum perforatum (St. John's wort)