RESUMEN
Marrow cytogenetic and granulocyte-macrophage colony formation (CFU-GM) studies were performed on 34 previously untreated patients with documented myelodysplastic syndromes seen between January 1978 and June 1982. All patients were managed without chemotherapy until progression to acute leukemia was observed. All 10 patients with exclusively abnormal marrow metaphases developed acute leukemia (100%) while only one (7%) of 14 patients with solely normal marrow metaphases subsequently developed leukemia (p less than 0.001). Three (42%) of the seven patients with both normal and abnormal marrow metaphases developed acute leukemia. Fifteen (86%) of the 19 patients with either large cluster or no growth patterns developed acute leukemia while only two (13%) of 15 patients with either small cluster or colony forming growth patterns developed acute leukemia (p less than 0.001). Abnormal marrow cytogenetic status correlated with abnormal marrow CFU-GM growth pattern (p less than 0.05). Analysis of CFU-GM sensitivity to inhibition by prostaglandin E was performed in 12 patients. Nine patients showed CFU-GM refractoriness to inhibition by prostaglandin E. Seven of these patients eventually developed leukemia. Three patients had CFU-GMs which were initially sensitive to prostaglandin E inhibition. In these three patients, a loss of CFU-GM sensitivity to prostaglandin E was observed prior to their progression to morphologically identifiable acute leukemia.