High‐dose retinol in children with acute myelogenous leukemia in remission

In a single-institution study, 23 consecutive children with acute myeloid leukemia (AML) have been treated with a protocol including doxorubicin, cytarabine and 6-thioguanine as induction therapy, followed by four courses of high-dose cytarabine as consolidation. Total duration of chemotherapy was 6–8 months from diagnosis. 21 out of the 23 children achieved complete remission. During remission, the children received 52 μmol (50000 I.U.) retinol as retinyl paimitate per square meter daily. 14 of the 21 children are still in their first remission with a mean observation time of 36 months. In our study retinyl ester given in doses up to 30 times the recommended daily allowances has not caused any clinical or biochemical side effect for up to 4 yr of therapy.