PRIOR CONCURRENT THERAPY: Biologic therapy: Not specified Chemotherapy: Not specified Endocrine therapy: At least 3 months since prior hormonal therapy OR No concurrent estrogen Other concurrent hormonal therapy allowed if stable regimen for more than 3 months Radiotherapy: At least 4 weeks since prior radiotherapy and recovered Surgery: See Disease Characteristics At least 3 weeks since prior surgery and recovered Other: At least 6 weeks since prior antibiotics No concurrent genotoxicity therapy