DETECTION OF TUMOR-CELLS IN THE BONE-MARROW OF STAGE-IV BREAST-CANCERPATIENTS RECEIVING HIGH-DOSE CHEMOTHERAPY - THE ROLE OF INDUCTION CHEMOTHERAPY

High-dose chemotherapy and hematopoietic support can produce long-term , disease-free remissions in selected patients with metastatic breast cancer. Occult bone marrow involvement may contribute to late relapse. We used five anti-breast cancer monoclonal antibodies and flow cytome try with cytological analysis of sorted immunostained cells to detect tumor cells in the bone marrow in two cohorts of patients. The first ( Upfront) cohort was treated with a single course of high-dose chemothe rapy and autologous bone marrow support (ABMS) without induction chemo therapy. The second (AFM) cohort received induction chemotherapy with doxorubicin, 5-fluorouracil and methotrexate prior to high-dose chemot herapy and ABMS. Of the 15 Upfront patients, seven (47%) had immunosta ined cells in the harvested bone marrow by flow cytometry and 8/15 (53 %) had positive cytologies. Of the 49 AFM patients studied, nine (18%) had immunostained cells in the bone marrow, and only 1/49 (2%) had po sitive cytologies. Induction chemotherapy significantly decreased bone marrow contamination as detected by flow cytometry and cytology in pa tients with breast cancer. The detection of immunostained cells in the bone marrow did not predict for relapse or overall survival.