Objective:To investigate the clinical efficacy and safety of bendamustine combination regimen in the treatment of patients with relapsed or refractory multiple myeloma (RRMM).Methods:From March 2020 to December 2020, 16 patients with RRMM were treated with bendamustine combination regimen in Beijing Jishuitan Hospital. The efficacy and adverse events (AEs) of bendamustine combination regimen were retrospectively analyzed in the 16 patients.Results:The median treatment lines for 16 patients with RRMM who received bendamustine combination regimen was 4 lines, and the median course of treatment was 3 (1-8). The median follow-up time after bendamustine treatment started was 5.3(1.3-9.2)months. Among the 16 cases, the disease control rate (DCR), overall response rate(ORR), and ≥ very good partial remission (VGPR) rate were 13/16, 5/16, 4/16 respectively. The median PFS was 4.9 months. Among them, the ORR of bendamustine combined with immunomodulators was higher. AEs were anemia, leukopenia, neutropenia, thrombocytopenia and fatigue. No patients who stopped treatment and adjusted the dose due to AEs.Conclusions:Bendamustine combination regimen is an effective and safe regimen for relapsed/refractory multiple myeloma.

Objective:To investigate the clinical efficacy and safety of ixazomib-based therapy in patients with relapsed or refractory multiple myeloma (RRMM) .Methods:A retrospective analysis was performed on the efficacy and adverse reactions of 53 RRMM patients treated with a combined regimen containing ixazomib in the Hematology Department of Beijing Jishuitan Hospital from July 8, 2018 to November 30, 2020. Among them, 6 patients received ID regimen (ixazomib + dexamethasone) , 30 patients received ID regimen + immunomodulator, and 17 patients received ID regimen + other chemotherapy drugs.Results:Fifty-three patients with RRMM received ixazomib-based therapy. The median previous treatment line was 3, the median treatment course was 6 (2-30) , and the median follow-up time was 21 months (2-32 months) . The overall response rate (ORR) was 54.7% (29/53) after 2 courses of treatment. Among them, 26.4% (14/53) had very good partial response (VGPR) and 28.3% (15/53) had partial response (PR) . The ORR of the ID regimen group, ID regimen + immunomodulator group and ID regimen + other chemotherapy group were 83.3% (5/6) , 56.7% (17/30) and 41.2% (7/17) respectively, with no statistically significant difference among the three groups ( P=0.208) . The median time to progression (TTP) of 53 patients was 8 months (1-24 months) . The most frequent adverse events of ixazomib treatment were gastrointestinal reactions such as nausea, vomit and diarrhea, with an incidence of 37.7% (20/53) , and the incidence of grade 3-4 was 5.7% (3/53) . The most common hematological adverse events were thrombocytopenia (15.1%, 8/53) , neutropenia (11.3%, 6/53) and anemia (9.4%, 5/53) . Grade 1-2 peripheral neurotoxicity occurred in only 7.5% (4/53) of patients. Conclusion:Ixazomib has good efficacy and safety for the patients with RRMM in the real world.

Objective:This study analyzed the expression of CD24 antigen on bone marrow plasma cells (BMPC) of patients with multiple myeloma (MM) and the predictive value of induction therapy.Methods:This clinical observational study utilized 258 MM patients samples treated at the Hematology Department of Beijing Jishuitan Hospital who met the inclusion criteria in the Department of Hematology, Capital Medical University, from August 12th, 2022 to February 1st, 2024. According to the different stages of the disease, patients were divided into three groups: 78 cases of Newly Diagnosed Multiple Myeloma(NDMM) (42 males and 36 females, aged 62±11), 56 cases of the relapse refractory group (34 males and 22 females, aged 64±9), and 124 cases of the disease remission group (68 males and 56 females, aged 62±10). Multiparameter flow cytometry (MFC) was used to detect the expression level of CD24 antigen on BMPC and the relationship between CD24 and MM disease status. The clinical data and test results of 78 NDMM patients at initial diagnosis were retrospectively analyzed, including gender, age, MFC detection of the positive expression rate of antigens (CD19, CD20, CD24, CD27, CD56), the results of efficacy evaluation after induction therapy, ISS staging, R-ISS staging, blood hemoglobin, β2-microglobulin, human serum albumin, serum creatinine, lactate dehydrogenas, correction of calcium, BMPC ratio, and the results of FISH. The patients were divided into a deep remission group [including complete remission (CR) and very good partial remission (VGPR)] with 43 cases and a non-deep remission group (non CR and VGPR) with 17 cases according to the difference of antigen positive expression rate after induction therapy. The differences of antigen expression on BMPC between the two groups were compared. Binary logistic regression was used to analyze the relationship between the expression of each antigen and the efficacy after induction therapy in patients, and the results showed that CD24 was more correlated with the achievement of deep remission after induction therapy than other antigens. Therefore, taking the positive expression rate of CD24 in NDMM patients at the initial diagnosis and deep remission after induction therapy as the research objects, the predictive value of CD24 for NDMM patients reaching deep remission after induction therapy was analyzed by using receiver operating characteristic curve (ROC), and the optimal cutoff value was obtained. NDMM was divided into two groups according to the cut-off value, and the differences between the two groups in clinical baseline data and prognostic indicators were compared.Results:The positive rates of plasma cell CD24 expression in the NDMM group, the relapse refractory group and the disease remission group were 2.18 (95% CI 0.08-81.85)%, 3.81 (95% CI 0.10-64.56)%, 8.74 (95% CI 0.79-95.55)% respectively. Compared with the disease remission group, the NDMM and relapse refractory group was lower ( Z=-7.889, -5.282, respectively, P<0.001). Univariate analysis showed that there was a significant difference in the positive expression rate of CD24 at initial diagnosis between the deep remission group and the non-deep remission group ( Z=-3.265, P<0.001), while there was no significant difference in CD19 ( Z=-0.271, P=0.787), CD20 ( Z=-0.205, P=0.837), CD27 ( Z=-0.582, P=0.560), and CD56 ( Z=-0.328, P=0.743) between the two groups. Binary logistic regression analysis showed that compared with other antigens [CD19 ( OR=1.045, 95% CI 0.975-1.120, P=0.217), CD20 ( OR=1.000, 95% CI 0.971-1.030, P=0.976), CD27 ( OR=0.997, 95% CI 0.977-1.016, P=0.734), CD56 ( OR=1.006, 95% CI 0.990-1.006, P=0.449)], the expression of CD24 ( OR=0.423, 95% CI 0.990-1.006, P=0.449) on BMPC in NDMM patients was most closely related to the achievement of deep remission was achieved after induction therapy. The lower the proportion of CD24 at the initial diagnosis was, the lower the probability of achieving deep remission after induction therapy was. The area under the curve (AUC) of CD24 in predicting deep remission after induction therapy was 0.772 (95% CI 0.655-0.889, P=0.001), with a sensitivity of 60.50%, a specificity of 85.00%, and the optimal critical value was 2.21%. Compared with the group with plasma CD24 positive rate>2.21%, the group with plasma CD24 positive rate<2.21% had a higher proportion of male (39.47%vs 65.00%, χ2=5.092, P=0.024), ISS stagingⅢ (41.67% vs 58.33%, χ2=6.175, P=0.046), β2 microglobulin (3.19 mg/L vs 4.14 mg/L, Z=-2.257, P=0.024), and BMPC [(8.672±1.827)% vs (19.530±3.188)%, t=-2.963, P=0.004] detected by MFC, and the differences were statistically significant. Conclusions:The low positive rate of plasma cell CD24 is closely related to the higher tumor burden and the worse disease status of MM patients. In addition, the positive expression rate of CD24 is at initial diagnosis can predict the efficacy achieved after induction therapy, and the lower positive rate of CD24 is, the worse the efficacy achieved after induction therapy. At the same time, MFC detection of CD24 is convenient and efficient in the evaluation and prediction of MM.