Comparison of multiplex reverse transcription polymerase chain reaction and conventional cytogenetics as a diagnostic strategy for acute leukemia.

To clarify the usefulness of multiplex reverse transcription polymerase chain reaction (mRT-PCR) in diagnosing acute leukemia, mRT-PCR detecting 28 different translocations was performed on bone marrow aspirates of 156 patients with acute leukemia, and the results were compared with conventional chromosomal karyotypes. About 113 of 156 patients had acute myeloid leukemia (AML), and 36 had acute lymphoid leukemia (ALL) with patients' ages ranging from 1 to 84 (median: 34.5). Concordance rate between karyotyping and mRT-PCR was 50% (51% in AML and 44% in ALL). Karyotype revealed chromosomal abnormalities in 70 patients (45%) while mRT-PCR showed some aberrations in 59 patients (38%). mRT-PCR detected t(1;19), t(4;11), t(9;11), t(10;11), t(11;19), t(12;21), and TAL1d, which were not detected by G-banding. In addition, 10 patients with t(15;17), one patient with t(8;21), and four patients with t(9;22) detected by mRT-PCR revealed normal karyotypes. However, mRT-PCR did not detect numerical abnormalities, deletions, and translocations other than the 28 translocations included in the assay as expected. In conclusion, although it cannot be a substitute of the conventional chromosome analysis, mRT-PCR could be a complementary diagnostic strategy of acute leukemia.