Achievement of a complete cytogenetic response with hydroxyurea in a patient with chronic myelogenous leukemia

Hydroxyurea rarely produces a complete cytogenetic remission in patients with chronic myelogenous leukemia (CML). In this report, we describe one case of the CML patient who achieved complete cytogenetic remission (no Ph chromosome in 20-25 metaphase cells) by treatment with hydroxyurea alone. By the fluorescent in situ hybridization (FISH) methodology using bcr/abl specific translocation probe, sequential bone marrow specimens from the patient showed the characteristic 9;22 translocation at a higher rate (9-10%) than the normal control range (2.49-4.88%) at the time of complete cytogenetic remission. Thus, it is suggested that FISH is a more sensitive method to detect the bcr/abl fusion gene than conventional cytogenetic analysis for the detection of minimal residual disease in CML.