High-Throughput Sequencing Technology for Detection of Gene Mutations in Myeloid Malignancies and Its Clinical Prognostic Significance / 中国实验血液学杂志

OBJECTIVE@#To detect the gene mutations in patients with myeloid malignancies by high-throughput sequencing and explore the correlation between gene mutations and prognosis.@*METHODS@#A retrospective analysis was performed on 56 patients with myeloid malignancies who were hospitalized in the department of hematology, Peking University International Hospital from January 2020 to May 2021. The genetic mutations of the patients were detected by next-generation sequencing technology, and the correlation between the genetic mutations and prognosis of myeloid malignancies was analyzed.@*RESULTS@#In 56 patients, the number of mutated genes detected in a single patient is 0-9, with a median of 3. Sequencing results showed that the most common mutated genes were RUNX1(21.4%), TET2(17.9%), DNMT3A(17.9%), TP53(14.3%) and ASXL1(14.3%), among which the most common mutations occurred in the signaling pathway-related genes (23.3%) and the transcription factor genes (18.3%). 84% of the patients carried multiple mutated genes (≥2), and correlation analysis showed there were obvious co-occurring mutations between WT1 and FLT3, NPM1 and FLT3-ITD, and MYC and FLT3. TP53 mutation was more common in MDS patients.The overall survival time of patients with NRAS mutation was significantly shortened (P =0.049). The prognosis of patients with TP53 mutation was poor compared with those without TP53 mutation, but the difference wasn't statistically significant (P =0.08).@*CONCLUSION@#The application of next-generation sequencing technology is of great significance in myeloid malignancies, which is helpful to better understand the pathogenesis of the disease, to judge the prognosis and to find possible therapeutic targets.

Clinical characteristics and prognosis of MLL-AF6 positive patients with acute myeloid leukemia / 北京大学学报(医学版)

OBJECTIVE@#To investigate the clinical features and prognosis of acute myeloid leukemia (AML) patients with the mixed lineage leukemia (MLL) gene rearrangements AF6 (MLL-AF6) positive.@*METHODS@#In the study, 11 patients who were newly diagnosed with MLL-AF6 positive AML were analyzed retrospectively, related literature was reviewed to clarify the clinical features and prognosis of MLL-AF6 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 55.5×109/L. Immunotype showed the expression of myeloid/monocyte and early stem cell series antigens. The expression level of MLL-AF6 fusion gene (real-time quantitative PCR) was 14.2%-214.5%, and 6/11 cases (54.5%) were associated with high EVI1 gene expression. Mutations of KRAS, TET2, ASXL1, TP53, DNMT3A, and FLT3-ITD 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 MLL-AF6 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 EVI1 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.

Observation on the efficacy of consolidation chemotherapy combined with allogeneic natural killer cell infusion in the treatment of low and moderate risk acute myeloid leukemia / 中华血液学杂志

Objective: To evaluate the efficacy of consolidation chemotherapy combined with allogeneic natural killer (NK) cell infusion in the treatment of low or intermediate-risk (LIR) acute myeloid leukemia (AML) . Methods: A cohort of 23 LIR AML patients at hematologic complete remission (CR) received NK cell transfusion combined with consolidation chemotherapy after 3 consolidation courses from January 2014 to June 2019 were reviewed. Control group cases were concurrent patients from Department of Hematology, and their gender, age, diagnosis, risk stratification of prognosis, CR and the number of courses of consolidate chemotherapy before NK cell transfusion were matched with LIR AML patients. Results: A total of 45 times of NK cells were injected into 23 LIR AML patients during 4 to 7 courses of chemotherapy. The median NK cell infusion quantity was 7.5 (6.6-8.6) ×10(9)/L, and the median survival rate of NK cells was 95.4% (93.9%-96.9%) . Among them, the median CD3(-)CD56(+) cell number was 5.0 (1.4-6.4) ×10(9)/L, accounting for 76.8% (30.8%-82.9%) ; The number of CD3(+) CD56(+) cells was 0.55 (0.24-1.74) ×10(9)/L, accounting for 8.8% (4.9%-20.9%) . Before NK cell infusion, the number of patients with positive MRD in the treatment and control groups were 9/23 (39.1%) and 19/46 (41.3%) (χ(2)=0.030, P=0.862) respectively. After NK infusion, There was no significant difference in terms of MRD that went from negative to positive between the treatment and the control groups (14.3% vs 22.2%, χ(2)=0.037, P=0.847) . In the treatment group, 66.7% (6/9) of the MRD were converted from positive to negative, which was significantly higher than that in the control group (10.5%, 2/19) (χ(2)=6.811, P=0.009) . Morphological recurrence occurred in 1 case of MRD negative in the treatment group and 2 cases of MRD positive in the control group. By the end of follow-up, the median follow-up was 35 (10-59) months, the number of patients with morphological recurrence in the treatment group was 30.4% (7/23) , which was significantly lower than that in the control group (50.2%, 24/46) (χ(2)=2.929, P=0.087) , although there was no statistically significant difference between the two groups. There was no significant difference on MRD-negative between the treatment and the control groups (43.5% vs 43.5%, χ(2)=1.045, P=0.307) . The 3-year leukemia-free survival was better in the treatment group [ (65.1±11.1) %] than that in the control group [ (50.0±7.4) %] (P=0.047) . The 3-year overall survival in the treatment and control groups were (78.1±10.2) % and (65.8±8.0) % (P=0.212) , respectively. Conclusion: The consolidation of chemotherapy combined with allogeneic NK cell infusion contributed to the further remission of patients with LMR AML and the reduction of long-term recurrence.

Risk factors for recurrent thrombosis in patients with polycythemia vera and essential thrombocythemia / 中华血液学杂志

Objective: To analyze the clinical characteristics of recurrent thrombosis in patients with polycythemia vera (PV) and essential thrombocythemia (ET) to probe the risk factors for recurrent thrombosis in patients with ET and PV. Methods: The clinical data of 104 ET and PV patients with thrombosis in Beijing Anzhen Hospital from February 2001 to November 2016 were retrospectively analyzed. Thrombosis reoccurred in 38 patients. Statistical analyses were performed by multivariate logistic regression for risk factors of recurrent thrombosis in ET and PV patients. Results: Recurrent thrombosis occurred in 36.5% of patients with ET/PV, the total incidence rate in ET and PV patients was 9.8% patient-years, 12.3% patient-years and 5.7% patient-years in ET and PV respectively. There were a total of 56 re-thrombotic events, and 42.1% of events occurred within 1 year after the first thrombosis. The arterial re-thrombosis was 97.4% (most of acute coronary syndrome, ACS), and venous events was 2.6%. The most common cases of re-thrombosis were ACS in ET patients (18 cases, 64.3%), and cerebral infarction in PV patients (7 cases, 70.0%). The number of PV patients with 2 times or more re-thrombotic events was significantly higher than that of ET patients (9 cases, 90.0% vs 7 cases, 25.0%). The proportion of the patients with WBC>12.5×10(9)/L or Hct>45%, and thrombosis history or splenomegaly and high risk thrombotic events were higher than those with a single thrombus (52.6% vs 31.8%; 50.0% vs 30.0%; 86.8% vs 13.6%; 84.2% vs 33.3%; 52.6% vs 15.2%; 94.7% vs 53.0%; P values were 0.036,0.046, <0.001, <0.001, <0.001 and <0.001, respectively). Logistic regression analysis showed that thrombosis history (OR=13.697, P=0.025), splenomegaly (OR=13.301, P=0.034) and high risk stratification of thrombotic events (OR=44.618, P=0.025) were independent risk factors for recurrent thrombotic events. Conclusions: ET and PV patients had a higher risk of re-thrombosis. The incidence of re-thrombosis in ET was higher than in PV, ACS was more common cases of re-thrombotic events; but PV patients were more susceptible to multiple re-thromboses than ET ones, also with more cerebral infarction. Previous thrombus history, splenomegaly and high risk stratification of thrombotic events were independent risk predictors for re-thrombosis of ET and PV patients.