Inclusion Criteria

DISEASE CHARACTERISTICS: Histologically or cytologically proven unresectable, locally
recurrent, or metastatic breast cancer not amenable to surgery or radiotherapy of curative
intent No inflammatory breast cancer unless evidence of metastatic disease No bone
metastases, pleural effusion, or ascites as the only site of disease Clinically measurable
disease outside previously irradiated area Relapse after 1 prior adjuvant or neoadjuvant
chemotherapy regimen containing anthracycline unless clinically contraindicated No known
or suspected brain metastases or recurrence requiring steroids or radiotherapy Hormone
receptor status: Not specified

PATIENT CHARACTERISTICS: Age: 18 and over Sex: Female Menopausal status: Not specified
Performance status: Karnofsky 70-100% Life expectancy: At least 12 weeks Hematopoietic:
Absolute granulocyte count at least 1,500/mm3 Platelet count at least 100,000/mm3
Hemoglobin at least 9.0 g/dL Hepatic: ALT and AST no greater than 2 times upper limit of
normal (ULN) Bilirubin no greater than 1.5 times ULN Renal: Calcium no greater than 1.2
times ULN Creatinine no greater than 1.5 times ULN Cardiovascular: No active uncontrolled
cardiac disease and/or myocardial infarction within the past 6 months Other: Not pregnant
or nursing Negative pregnancy test Fertile patients must use effective contraception
during and for 3 months after completion of study No other prior malignancy within the
past 5 years except adequately treated basal cell or squamous cell skin cancer or
carcinoma in situ of the cervix No other serious systemic disorder precluding study No
active infection No severe psychiatric disease No history of hypersensitivity reactions to
polyoxyethylated castor oil-based drugs

PRIOR CONCURRENT THERAPY: Biologic therapy: No prior bone marrow transplantation or
autologous stem cell infusion following high-dose adjuvant chemotherapy for metastatic
disease No concurrent immunotherapy (including humanized anti-HER2 antibody) Chemotherapy:
See Disease Characteristics See Biologic therapy No prior chemotherapy for metastatic
breast cancer No prior gemcitabine or taxane No other concurrent chemotherapy Endocrine
therapy: See Disease Characteristics Prior antitumoral hormonal therapy allowed No
concurrent hormonal therapy excluding contraceptives and replacement steroids
Radiotherapy: See Disease Characteristics At least 2 weeks since prior radiotherapy and
recovered No concurrent radiotherapy Surgery: See Disease Characteristics Other: Recovered
from prior therapy At least 30 days since prior investigational drugs No concurrent
investigational drugs Concurrent bisphosphonate therapy allowed if not begun or stopped
within 4 weeks before study