TUMOR-CELL CONTAMINATION OF PERIPHERAL-BLOOD STEM-CELL TRANSPLANTS AND BONE-MARROW IN HIGH-RISK BREAST-CANCER PATIENTS

Twenty-one high-risk patients with primary stage II/III breast cancer were treated with high-dose chemotherapy comprising etoposide, ifosfam ide, carboplatin and epirubicin (VIC-E), Tumor cells of epithelial ori gin were analyzed using the monoclonal antibodies CK2 (IgG(1)) and A45 -B/B3 (IgG(1)) against cytokeratin (CK) components in bone marrow (BM) aspirates prior to chemotherapy, and in peripheral stem cell transpla nts (PBSCT), They were separated after the first (21/21 patients) and the second cycle (16/21 patients) of induction chemotherapy with VIP-E (etoposide, ifosfamide, cisplatin, epirubicin), Preliminary results s howed CK positive tumor cells in 40% (14/35) of the analyzed transplan ts, In 7/12 (58.3%) patients, CK positive tumor cells were detectable in BM prior to treatment, Sixteen patients were separated after the 1s t and 2nd cycle of VIP-E, PBSCT of 14/16 patients were assessable for presence of CK positive tumor cells, Our preliminary results demonstra te a lower tumor cell contamination of PBSCT separated after the 2nd c ycle of induction therapy (14.3%) compared to contamination after the first induction therapy (64.3%), To date, 4/21 patients have experienc ed a relapse, and three of these patients had tumor cell positive tran splants, Due to the small patient number only a trend towards a superi or relapse-free survival in the patient group with CK negative transpl ants can be shown by Kaplan-Meier analysis.