Evaluation of cytogenetic samples and pertinent technical variables in adult acute lymphocytic leukemia

Data on 200 bone marrow and peripheral blood samples received from 190 adults with acute lymphoblastic leukemia (ALL) were analyzed with respect to sample type (bone marrow or peripheral blood), sample cell count (concentration and total count), time in transit (days), and year of analysis. Each sample was assessed for 1) number and quality of metaphases, and 2) presence or absence of a clone. Sample type, concentration of cells, time in transit, and year of analysis all significantly affected the number and quality of metaphases and the detection of a clone. The chance of obtaining 10 or more cells for cytogenetic analysis in adult ALL was shown to be as low as 10% with a suboptimal sample (peripheral blood, low cell concentration) and as high as 70% with an optimal sample (bone marrow, adequate cell concentration, 1 day or less in transit). The likelihood of detecting a clone was smallest (0%) for the group (bone marrow, adequate cell concentration, 2 or more days in transit) and greatest (68%) in the optimal group (bone marrow, adequate cell concentration, 1 day or less in transit).