CLINICAL-FEATURES INFLUENCING THE DETECTION OF BCR-ABL TRANSCRIPTS AFTER ALLOGENEIC BONE-MARROW TRANSPLANTATION FOR CHRONIC MYELOGENOUS LEUKEMIA

BACKGROUND: TO evaluate the relationship between clinical parameters a nd the ability to detect BCR-ABL-positive cells in a series of 27 long survivor patients after allogeneic bone marrow transplantation (BMT) for chronic myelogenous leukemia (CML). PATIENTS AND METHODS: A total of 78 samples obtained between 1 and 160 months after BMT were analyze d for the presence of the BCR-ABL transcript detected by the reverse-t ranscription polymerase chain reaction (PCR) using nested primers. Med ian follow up was 83 months. RESULTS: 16 patients were persistently PC R-positive and 7 patients persistently PCR-negative. The original tran script became negative in four patients. Only two of the positive case s developed hematologic relapse during the period of study. High white blood cell counts before BMT (17.88 vs 10.12 x 10(9)/I; p = 0.008) an d immunosuppressive therapy for chronic graft-versus-host disease (p < 0.05) were associated with an increased ability to detect residual BC R-ABL positive cells. CONCLUSIONS: Our data show that most patient are persistently BCR-ABL positive after BMT for CML. If these findings re presents a dynamic balance between the tumour burden prior BMT and the immunological capability of the graft must be confirmed in further st udies.