PROGNOSTIC IMPACT OF KARYOTYPE AND IMMUNOLOGICAL PHENOTYPE IN 125 ADULT PATIENTS WITH DENOVO AML

One hundred-twenty-five adult patients with de novo acute myeloid leukemia (AML) were treated according to a standard 7 + 3 induction regimen. Karyotype and immunological phenotype of blasts examined prior to treatment were correlated with each other, with response to treatment and duration of survival. The following monoclonal antibodies (mAbs) were used for immunological phenotyping: VIM-D5 (CD15), MY7 (CD13), MY9 (CD33), VIM-2 (CDw65), VIM-13 (CD14), 63D3 (CD14), VID-1 (anti HLA-DR), WT1 (CD7), CLB-Ery3 (antiblood group H antigen), C17-27 (CD61), and an antiserum against TdT. Despite a considerable overlap between the individual groups, patients with specific aberrations as defined by the MIC classification (n = 39) showed distinct, characteristic, myeloid or myelomonocytic immunophenotypes. In M2/t(8;21) there was a significant association with negativity to CD13, in M3/t(15;17)with negativity to CD15 and HLA-DR, whereas in M4/inv(16) expression of blood group H antigen was unexpectedly found. The response to therapy, as well as rate of complete remission as duration of survival, was better in patients with M2/t(8;21), M3/t(15;17), and M4Eo/inv(16) as compared to all other patients and significantly worse in patients with M5a/t/del(11)(q23). In 35 patients with normal karyotpye and 16 patients with cytogenetic anomalies not presently associated with FAB subtypes the expected correlations of rather immature myeloid immunologic phenotypes with M1 and M2 morphology and CD14 expression in monoblastic leukemias was found. Remission rate and survival were significantly worse in 19 patients with complex nonrandom aberrations, where blast cell expression of blood group H antigen and of TdT were significantly increased.