Comparison of circulating colony-forming cells in chronic granulocytic leukemia and leukemoid reaction.

In vitro culture studies of peripheral blood leukocytes using semi-solid media from 8 patients with chronic granulocytic leukemia (CGL) and 5 patients with granulocytic leukemoid reaction were performed. A markedly increased number of circulating colony-forming units were present in patients with CGL (mean 343 +/- 47) as opposed to those having granulocytic leukemoid reaction (mean 7.0 +/- 4). The colony size was larger in CGL than in granulocytic leukemoid reaction or in normal peripheral blood.