The current status of genetic testing for leukemia]

The pathogenic chromosome translocations present in various hematological malignancies result in the formation of fusion genes, which are detected by a reverse transcription-polymerase chain reaction method. Furthermore, with this method, it is possible to sensitively detect minimal residual disease (MRD), which is difficult by a morphological testing. It has now been established that the detection of MRD is important for the diagnosis, treatment policy, evaluation of the prognosis, and monitoring of leukemia. In particular, quantitative analysis of MRD is important for evaluation of the curative effect and prediction of recurrence. In addition, mutation analysis is valuable to decide on the therapeutic protocol for imatinib-resistant patients, and the stratification of treatment for acute myeloid leukemia. At present, however, there is no standard laboratory procedure for genetic testing for leukemia. Here, the problems related to external precision management and analytical error are discussed.