[Clinical characteristics and prognosis of positive patients with acute myeloid leukemia].

OBJECTIVE

To investigate the clinical features and prognosis of acute myeloid leukemia (AML) patients with the mixed lineage leukemia () gene rearrangements () positive.

METHODS

In the study, 11 patients who were newly diagnosed with positive AML were analyzed retrospectively, related literature was reviewed to clarify the clinical features and prognosis of positive patients.

RESULTS

Among the 11 patients, there were 6 males and 5 females, with a median age of 36 years. Six patients were diagnosed with AML M5 and five with M4 according to FAB classification (French-American-British classification systems). Gingival swelling and pain occurred in 6 cases and fever occurred in 5 cases. At first diagnosis, the median white blood cells were 55.5×10/L. Immunotype showed the expression of myeloid/monocyte and early stem cell series antigens. The expression level of fusion gene (real-time quantitative PCR) was 14.2%-214.5%, and 6/11 cases (54.5%) were associated with high gene expression. Mutations of , , , , , and were detected by next generation sequencing (NGS) in 4 patients. Chromosome G banding examination showed that 2 cases were t(6;11)(q27, q23) with complex karyotype abnormality, 4 cases with +8 abnormality and 2 cases with normal karyotype. Hematological complete remission (CR) was achieved in 8/11 patients (72.7%) after conventional induction chemotherapy, and primary drug resistance was observed in 3 patients. Two of the eight patients with CR were negative for minimal residual disease (MRD), with a median CR duration of 4.5 months. Two patients with positive MRD and three patients with refractory recurrence underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT), but all died due to leukemia progression. At the end of follow-up on December 1, 2019, 2 patients were alive and 9 died, with median survival time of 9 months.

CONCLUSION

The AML patients with positive were mostly young, the majority of FAB types were M4 and M5, and most of the patients often had fever as the first symptom, with increased white blood cells, accompanied by organ infiltration, and high gene expression. The hematological remission rate of routine chemotherapy is not low, but it is difficult to achieve molecular remission, most of which have early recurrence. Early allo-HSCT in a molecular negative state may prolong the CR duration.