MINIMAL-RESIDUAL-DISEASE IN ACUTE-MONOCYTIC-LEUKEMIA PATIENT WITH TRISOMY-11 AND PARTIAL TANDEM DUPLICATION OF MLL

We studied MLL rearrangements in five patients with myeloid hematologi c malignancies with trisomy 12. Two had acute monocytic leukemia (AMoL ), one had chronic myelomonocytic leukemia, one had refractory anemia, and the other had juvenile chronic myelogenous leukemia. Only one pat ient, a 15-year-old boy with AMoL and simple trisomy 11, showed rearra ngement of MLL. He did not respond to chemotherapy, and successfully u nderwent bone marrow transplantation, but suffered a relapse 22 months later. Reverse transcription-polymerase chain reaction (RT-PCR) and s equencing analyses of bone marrow cells revealed a tandem duplication of MLL, and his relapse was predictable by sequential RT-PCR studies b efore it was clinically evident. Of 16 acute myeloid leukemia patients with trisomy 11 and rearrangement of MLL reported, our patient was th e youngest in age and the only one with AMol. (C) Elsevier Science Inc ., 1997.