Clinical utility of marrow cell tissue cultures in acute leukemia of childhood

To determine the clinical value of tissue culture techniques in the study of acute leukemia, marrows from 50 children (40 acute lymphoblastic [ALL], 10 acute myeloblastic [AML]) were cultured by the use of an AML blast colony assay and the CFU‐GEMM assay. In the AML assay, AML marrow gave rise to high numbers of blast colonies within 24 to 48 hr; in sharp contrast, 37 of 40 ALL marrows did not yield colonies in this assay. In the CFU‐GEMM assay, AML marrow produced excessive numbers of monocyte‐macrophage CFU‐C colonies, an obvious background of individual macrophages and clusters, and occasional blast colonies. ALL marrow yielded very low numbers of granulocytic CFU‐C colonies, no background of macrophage cells, and no blast colonies. These clear‐cut differences in cellular growth kinetics in vitro between ALL and AML marrows should allow confirmation of the type of acute leukemia within 24 to 48 hr. The colony assays may also be valuable in differentiating ALL from AML in difficult diagnoses when conventional approaches are nondiagnostic.