[Efficacy and Safety of Venetoclax-Based Induction Therapy in Acute Myeloid Leukemia].

AbstractObjective: To investigate the efficacy and safety of venetoclax-based induction chemotherapy in newly diagnosed (ND) patients ineligible for intensive therapy and patients with relapsed/refractory (R/R) acute myeloid leukemia (AML). METHODS: The clinical data of 51 newly diagnosed patients ineligible for intensive therapy and patients with R/R AML treated in the Department of Hematology of Xijing Hospital from February 1, 2021 to April 30, 2022 were retrospectively analyzed. The incidence of complete remission (CR)/CR with incomplete hematological recovery (CRi), objective remission rate (ORR), minimal residual disease (MRD) status, advense events (AE), overall survival (OS) and progression-free survival (PFS) were analyzed. RESULTS: Among 51 patients, 32 patients were newly diagnosed patients unfit for intensive therapy, with a median age of 60 (29-88) years, and 19 patients were R/R patients, with a median age of 49 (22-92) years. The median cycles of VEN-based treatment in the two groups were both 2. The CR/CRi rates in the ND-AML and R/R-AML group after one course of induction treatment were 65.6% and 36.9%, respectively, and the ORR were 81.3% and 42.1%, respectively. The cumulative CR/CRi rates after 1-3 courses of VEN-based treatment were 71.9% and 47.4%, respectively. The MRD negativity rates of patients achieving CR/CRi were 69.6% and 33.3%, respectively. In the ND-AML and R/R-AML group, the median PFS were 8(5-11) and 3(1-5) months, and the median OS were 13 (6-20) and 5 (3-7) months, respectively. The median OS of patients achieving CR/CRi in both groups was significantly better than that of patients not achieving CR/CRi (13 months vs 4 months; OS not reached vs 4 months). During the first induction cycle, the incidence of grade 3 or higher granulocytopenia, anemia and thrombocytopenia was 96%, 90.2% and 84.3%, respectively. 30 patients (58.8%) had granulocytopenia with fever. The most common non-hematological AE was infection (12/51, 23.5%), followed by gastrointestinal symptoms (6/51, 11.8%). CONCLUSION: The VEN-based strategy has good treatment response and tolerance in newly diagnosed patients unfit for intensive therapy and R/R AML. The most common AEs are hematological toxicities and infection.

Chromosome 1q21 gain is an adverse prognostic factor for newly diagnosed multiple myeloma patients treated with bortezomib-based regimens.

Chromosome 1q21 aberration is one of the most common cytogenetic abnormalities in multiple myeloma, and is considered an important prognostic factor. The present study analyzed the clinical relevance and prognostic impact of 1q21 gain in 194 patients with newly diagnosed multiple myeloma treated with bortezomib-based regimens. 1q21 gain was detected in 45.9% (89/194) of patients, and those with 1q21 gain had a worse prognosis. Strikingly, our results showed that excluding the effects of other coinciding genetic anomalies, patients carrying at least four copies of 1q21 had worse survival outcome. Moreover, del(13q) strongly correlates with 1q21 gain, and the coexistence of del(13q) and 1q21 gain plays an important role in reducing PFS and OS times. Therefore, 1q21 gain should be considered a high-risk feature in multiple myeloma patients treated with a bortezomib-based regimen.

[Clinical Characteristics and Prognosis of Systemic Anaplastic Large Cell Lymphoma].

OBJECTIVE: To evaluate the clinical characteristics, treatment and prognosis of systemic anaplastic large cell lymphoma(sALCL). METHODS: The clinical data of 90 cases with sALCL treated in the Department of Hematology of the Affiliated Xijing Hospital of Air Force Medical University from November 2018 to October 2021 were retrospectively analyzed. The clinical features, treatment and prognosis were summarized and the prognostic factors were investigated. RESULTS: There were 58 males and 32 females, with a median age of 32 (12-73) years old. 69 (76.7%) patients had Ann Arbor stage Ⅲ-Ⅳ disease and half of the patients had extranodal infiltration. The median age was 27(12-72) years of the 60 ALK+ patients while 53(15-73) years of the 30 ALK- patients, and it was significantly different in the age of onset between the two group(P<0.01). 88 patients received first line chemotherapy, and 50(568%) cases achieved complete remission(CR). IPI score≥3 was an independent risk factor for CR. The median progressive free survival(PFS) and overall survival(OS) of the patients were not reached. Multivariate analysis showed that no achievement of CR after first-line therapy was a significant prognostic factor influencing PFS and OS. CONCLUSION: sALCL mainly occurs in males and most patients were in advanced stage. Half of the patients had extranodal involvement. The CR rate after first-line chemotherapy was 568%, and IPI score≥3 was a significant prognostic factor for CR. No achievement of CR after first-line therapy is poorly prognostic for PFS and OS.

Conservative discrete-velocity method for the ellipsoidal Fokker-Planck equation in gas-kinetic theory.

A conservative discrete velocity method (DVM) is developed for the ellipsoidal Fokker-Planck (ES-FP) equation in prediction of nonequilibrium neutral gas flows in this paper. The ES-FP collision operator is solved in discrete velocity space in a concise and quick finite difference framework. The conservation problem of the discrete ES-FP collision operator is solved by multiplying each term in it by extra conservative coefficients whose values are very close to unity. Their differences to unity are in the same order of the numerical error in approximating the ES-FP operator in discrete velocity space. All the macroscopic conservative variables (mass, momentum, and energy) are conserved in the present modified discrete ES-FP collision operator. Since the conservation property in a discrete element of physical space is very important for the numerical scheme when discontinuity and a large gradient exist in the flow field, a finite volume framework is adopted for the transport term of the ES-FP equation. For nD-3V (n<3) cases, a nD-quasi nV reduction is specifically proposed for the ES-FP equation and the corresponding FP-DVM method, which can greatly reduce the computational cost. The validity and accuracy of both the ES-FP equation and FP-DVM method are examined using a series of 0D-3V homogenous relaxation cases and 1D-3V shock structure cases with different Mach numbers, in which 1D-3V cases are reduced to 1D-quasi 1V cases. Both the predictions of 0D-3V and 1D-3V cases match well with the benchmark results such as the analytical Boltzmann solution, direct full-Boltzmann numerical solution, and DSMC result. Especially, the FP-DVM predictions match well with the DSMC results in the Mach 8.0 shock structure case, which is in high nonequilibrium, and is a challenge case of the model Boltzmann equation and the corresponding numerical methods.

[Establishment of the retrovirus-mediated murine model with MLL-AF9 leukemia].

This study was purposed to establish a retrovirus-mediated murine model with MLL-AF9 leukemia, so as to provide a basis for further investigation of the pathogenesis and therapeutic strategy of MLL associated leukemia. Murine (CD45.2) primary hematopoietic precursor positively selected for expression of the progenitor marker c-Kit by means of MACS were transduced with a retrovirus carrying MLL-AF9 fusion gene. After cultured in vitro, the transduced cells were injected intravenously through the tail vein into the lethally irradiated mice (CD45.1). PCR, flow cytometry and morphological observation were employed to evaluate the murine leukemia model system. The results showed that MLL-AF9 fusion gene was expressed in the infected cells, and the cells had a dramatically enhanced potential to generate myeloid colonies with primitive and immature morphology. Flow cytometric analysis revealed that the immortalized cells highly expressed myeloid lineage surface markers Gr-1 and Mac-1. Moreover, the expression levels of Hoxa9 and Meis1 mRNA were significantly higher in the MLL-AF9 cells than that in control. The mice transplanted with MLL-AF9 cells displayed typical signs of leukemia within 6-12 weeks. Extensive infiltration leukemic cells was observed in the Wright-Giemsa stained peripheral blood smear and bone marrow, and also in the histology of liver and spleen. Flow cytometric analysis of the bone marrow and spleen cells demonstrated that the CD45.2 populations expressed highly myeloid markers Gr-1 and Mac-1. The leukemic mice died within 12 weeks. It is concluded that the retrovirus-mediated murine model with MLL-AF9 leukemia is successfully established, which can be applied in the subsequent researches.