Tipifarnib Plus Tamoxifen in Treating Women With Metastatic Breast Cancer

DISEASE CHARACTERISTICS: * Diagnosis of metastatic (stage IV) breast cancer * Evidence of disease progression * Measurable disease * Must have been previously treated with at least 1 hormonal therapy with either an aromatase inhibitor or an estrogen receptor (ER)-modulating drug in the adjuvant or metastatic setting and meets 1 of the following criteria: * Hormone-responsive disease: * Stable disease (no recurrence or progression for at least 6 months) * Objective response * Hormone-nonresponsive disease: * No stable disease * No objective response * Previously treated CNS disease allowed provided patient has a life expectancy of at least 3 months (phase I patients) (Phase I closed to accrual effective 10/23/2003) * No CNS metastases (phase II patients) * Hormone receptor status: * ER and/or progesterone receptor positive * NOTE: As few as 1% positive cells considered positive PATIENT CHARACTERISTICS: Age * 18 and over Sex * Female Menopausal status * Not specified Performance status * Zubrod 0-1 Life expectancy * See Disease Characteristics Hematopoietic * Absolute neutrophil count at least 1,500/mm\^3 * Platelet count at least 100,000/mm\^3 Hepatic * Bilirubin no greater than 2.0 mg/dL (unless evidence of Gilbert's disease) * SGOT and SGPT less than 3 times upper limit of normal (unless liver involvement by tumor) Renal * Creatinine no greater than 1.5 mg/dL Other * Not pregnant * Negative pregnancy test * Fertile patients must use effective nonhormonal contraception during and for 2 months after study participation * No medical or psychiatric condition that would preclude study participation PRIOR CONCURRENT THERAPY: Biologic therapy * Not specified Chemotherapy * No more than 2 prior chemotherapy regimens for metastatic disease (phase II patients) * No limitations on prior neoadjuvant or adjuvant regimens * At least 4 weeks since prior chemotherapy (6 weeks for nitrosoureas or mitomycin) Endocrine therapy * See Disease Characteristics * At least 6 months since prior tamoxifen * Concurrent stable dose of steroids allowed (phase I patients) (Phase I closed to accrual effective 10/23/2003) Radiotherapy * No concurrent radiotherapy Surgery * Concurrent surgery allowed provided the need for surgery is not due to disease progression Other * Recovered from all prior therapy * No prior warfarin * No concurrent cytochrome p450-inducing anti-convulsants * No other concurrent anticancer therapies * Concurrent bisphosphonates for bone metastases allowed