Study on properties of native and cultured leukemic cells with special reference to the diagnosis and prognosis of acute myelogenous leukemia

Abstract

Multiple parameters were investigated in 66 patients with acute myelogenous leukemia (AML). These parameters are clinical and hematological features, cell culture characteristics of leukemic cells, cytogenetics and enzymatic analyses. The study aims are to identify diagnostic confirmation indices and prognostic indices in AML. Results from clinical and hematological studies indicated that the unfavorable prognostic factors were advanced age high WBC count, high PB absolute leukemic cells and low PS absolute neutrophils. The cell culture study revealed that patients with low or very high proliferative capacity of their AML cells had survival much longer than those with intermediate proliferative capacity or no leukemic cell growth in culture (p < 0.001). In addition, the study also indicated that the more differentiative capacity of AML cells in cultures the longer survival of the patients, both in semisolid culture system (p = 0.015) and in liquid suspension culture (p = 0.001). Data from cytogenetic analyses of AML cells from 66 patients revealed that there was abnormal karyotype in 62.1% of the patients The major aberration was t(8;21) followed by abnormality of chromosome 11-short-arm. Type specific chromosome abnormalities were found; most of the patients with t(8;21) were confined in M2 subtype and all 4 patients with t(15;17) were in M3. Patients whose AML cells showed normal karyotype or t(8;21) exhibited favorable clinical outcome in comparison with other abnormalities, both in terms of patient survival (p = 0.017) and complete remission rate (p = 0.034). There were significant differences between AML patients and normal control in the activities of ADA (p < 0.001), PNP (p < 0.001) and the level of PNP/ADA ratio (p < 0.001). There was no difference in the activity of TdT between AML patients and normal individuals. No relationship between patient survival and activities of these enzymes was found. Since various parameters affected patient survival in a different degrees, the weighted scoring system was proposed by this author, using 4 important prognostic factors : age, absolute leukemic cells, cytogenetic findings and proliferative capacity of AML cells. The scoring system could classified the patients into 3 risk groups with differences in survival (p < 0.0001) and seems to be of great value in predicting survival of AML patients.