[Characteristics of 11 patients with acute myeloid leukemia accompanied with karyotype aberration t(6;9)]

This study was aimed to investigate the characteristics of 11 patients with acute myeloid leukemia (AML) accompanying with karyotype t(6;9). The laboratorial and clinical data were analyzed retrospectively, including immunophenotype analysis and result analysis of real-time quantitative PCR detection. The results showed that a high prevalence of M2 was observed. Among 11 cases, 6 of M2, 2 of M4, 2 of M5 and 1 of MDS-RAEBT were found according to FAB criteria. Ten patients had high counts of peripheral white blood cells. Bone marrow dysplasia was seen in only 2 cases, and basophilia occurred in 4 cases. Six patients carried additional cytogenetic aberrations apart from t(6;9). Immunophenotypic analysis showed that all patients were positive for CD117, CD33, CD13, HLA-DR, CD38 and CD123. No NPM1 mutation was observed in all patients and a high level of WT1 was detected in all patients (7/7), out of 7 patients FLT3-ITD mutation was detected in only 3 patients. Follow-up details were available for 7 patients, one of whom died before chemotherapy, and the remaining 6 patients all had no response to IA or DA regimen. Among the 6 patients, 3 did not response to subsequently chemotherapy and all died from infections in a short period after diagnosis, the other 3 patients achieved a complete remission after alternative chemotherapy, but 2 relapsed in a short time and died. It is concluded that AML with cytogenetic aberration of t(6,9) is a distinct disease with a very poor prognosis. The first line chemotherapy such as IA or DA regimen is not effective to such patients, and the effective treatment needs further study.