The prognostic value of in vitro cultures of erythroid and megakaryocyte progenitors in myelodysplastic syndromes.

The prognostic value of colony formation by granulocyte-macrophage progenitors (CFU-GM) in myelodysplastic syndromes (MDS) has been investigated in several studies. We studied the in vitro growth patterns of hematopoietic progenitors of 83 patients with an MDS to find out whether erythroid (BFU-E) and megakaryocyte (CFU-Meg) cultures yield additional prognostic information to that obtained with CFU-GM cultures. Thirty-nine of 82 patients showed normal CFU-GM colony formation; the others had either excessive growth of colonies/clusters or reduced growth. Five of 74 patients had normal BFU-E and nine of 39 patients normal CFU-Meg growth; the others showed reduced or absent colony formation. The cultures of each cell lineage had a similar prognostic impact: the patients with a normal growth pattern had a lower risk of developing leukemia and a longer survival than those with an abnormal growth pattern (significant difference or trend). All patients with normal BFU-E or CFU-Meg colony growth also had normal CFU-GM colony formation, and all patients with normal BFU-E growth also had normal CFU-Meg growth. Among the patients with normal CFU-GM cultures, those with normal erythroid or megakaryocyte colony formation had a trend towards a better outcome compared to those with an abnormal growth pattern in the same cell lineage. In conclusion, erythroid and megakaryocyte cultures did not significantly contribute to the prognostic information obtained with CFU-GM cultures in MDS.