Detection of bcr/abl mRNA in a case of chronic myelogenous leukemia in long-term remission: CML or sensitivity of detection?

Chronic myelogenous leukemia (CML) is a myelo-proliferative disorder which, after a chronic phase which lasts an average of 3 years, evolves into an acute disease which is resistant to chemotherapy. Nevertheless, a few studies have reported cases in which partial or complete hematologic, cytogenetic and/or molecular remission of the disease were observed either spontaneously or after non intensive chemotherapy, with or without medullar aplasia. Some of these patients later relapsed into a blast crisis. We report a case of CML with clinical and hematologic remission for 19 years after two cycles of busulphan not causing medullar aplasia, negative for the BCR/ABL gene by Southern blot but with the gene's mRNA detectable by hot start nested RT-PCR.