Initial blood fetal hemoglobin concentration is elevated and is associated wtih prognosis in children with acute lymphoid or myeloid leukemia.

We examined the relationship between initial blood fetal hemoglobin (HbF) concentration and prognosis in 100 children with leukemia. HbF concentration was usually elevated and ranged between 0 and 19.5 g/l. Multivariate analysis showed that, in patients with acute lymphoblastic leukemia (ALL), each increment of 1 g/l in initial HbF concentration resulted in a 1.13-fold rise in the risk of death or relapse (95% confidence limits 1.01-1.25, P less than 0.05). In patients with myeloid leukemias, each increment of 1 g/l in HbF was associated with a 1.20-fold (1.05-1.37, P less than 0.02) rise in the risk of death or relapse. In the patients with myeloid leukemias the mean initial HbF concentration was also higher (3.4 g/l; 0.5-19.5 g/l) than in the patients with ALL (1.1 g/l; 0-18.7 g/l; P = 0.08). Our results indicate that the degree of increase in HbF synthesis is associated with the degree of malignancy: the more aggressive the disease, the more augmented is the synthesis of HbF.