The prognostic significance of dynamic monitoring of minimal residual disease (MRD) status in patients with newly-diagnosed multiple myeloma / 中华血液学杂志

Objective: To evaluate the prognostic value of kinetic changes in minimal residual disease (MRD) status, as well as its relationship with risk stratification, therapeutic response and treatment in patients with newly-diagnosed multiple myeloma (MM) . Methods: A total of 135 patients with newly-diagnosed MM were screened, and 105 patients who achieved VGPR or more as the best responses were included into this study. The MRD status was determined by multiparameter flow cytometry (MFC) at multiple intervals after two cycles of treatment until clinical relapse, death, or last follow-up. The statistical methods included Kaplan-Meier analysis, Cox regression, etc. Results: ①In all 135 patients, 57.8% (78/135) patients achieved MRD negativity (MRD(-)) after treatment. In 105 patients who achieved VGPR and thus included in this study, the MRD(-) rate was 72.4% (76/105) , with a median interval of 3 months from starting treatment to achievement of MRD(-) status. ②The 2-year PFS rate of patients with MRD(-) status was significantly higher than that of MRD(+) status (62.2% vs 41.3%, P=0.001) , while MRD persistence (MRD(+)) was an independent factor for poor prognosis (multivariate analysis for PFS: P=0.044, HR=3.039, 95%CI 1.029-8.974) . ③Loss of MRD(-) status (i.e., MRD reappearance) showed inferior outcomes compared with MRD sustained negative ones, the PFS was 18 months versus not reach (P<0.001) and the OS was not reach for both (P=0.002) . ④The 2-year PFS and OS rates of patients with duration of MRD(-)status≥12 months were significantly higher than those of the control group (PFS: 77.7% vs 36.7%, P<0.001; OS: 96.4% vs 57.9%, P<0.001 respectively) . Duration of MRD(-) status was associated with a marked reduction in risk of relapse or death (univariate analysis for PFS: P<0.001, HR=0.865, 95%CI 0.815-0.918; for OS: P=0.001, HR=0.850, 95%CI 0.741-0.915 respectively) . ⑤Moreover, even in patients carrying high-risk cytogenetic abnormalities (CA) or ineligible for ASCT, MRD negativity remained its prognostic value to predict PFS (high-risk CA medianPFS: not reach vs 19 months, P=0.006; ineligible for ASCT medianPFS: not reach vs 25 months, P=0.052 respectively) . ⑥Last, treatment with the bortezomib-based regimens contributed to prolonged MRD(-) duration (median MRD(-) duratio: 25 months vs 10 months, P=0.034) . Conclusion: Our findings supported MRD(+) status as an independent poor prognostic factor in MM patients, which implicated that duration of MRD(-) status also played a significant role in evaluation of prognosis, while loss of MRD(-)status might serve as an early biomarker for relapse. Therefore, monitoring of MRD kinetics might more precisely predict prognosis, as well as guide treatment decision, especially for when to start retreatment in relapsed patients.

Effect of 1q21 amplification on bortezomib therapeutic response and prognosis of newly diagnosed multiple myeloma patients / 中华血液学杂志

Objective: To investigate the effect of 1q21 amplification (1q) on the therapeutic response and prognosis of bortezomib(Btz) in the treatment of newly diagnosed multiple myeloma (MM) patients. Methods: A total of 180 newly diagnosed MM were included for analyses of clinical characteristics, cytogenetics, objective response rate (ORR), progression-free survival (PFS) and overall survival (OS), retrospectively. Gene expression profiling (GEP) was analyzed using publicly available R2 platform. Results: ① In 180 patients, 1q was found in 51.1% cases. Of them, 174 patients had complete follow-up data, including 88 cases with 1q and 86 without 1q (non-1q). ②Incidence of 1q was positively associated with percentage of IGH rearrangement (72.2%, P=0.017) and 1p deletion (1p) (27.8%, P=0.040). ③ The median PFS was 15.0 and 20.3 months for the 1q group and non-1q group, and the median OS was 29.4 and 44.0 months, respectively. Both PFS and OS of 1q group was significantly shorter than those of the non-1q group (P=0.029 and 0.038, respectively). Multivariate analysis further revealed that 1q was an independent prognostic factor for both PFS (HR=1.910, 95% CI 1.105-3.303, P=0.020) and OS (HR=2.353, 95% CI 1.090-5.078, P=0.029). ④ In 91 evaluable cases with 1q, very good partial remission (VGPR) rate was higher after treatment with Btz than those without Btz (62.1% vs 40.0%, P=0.032). Of note, the patients with 1q who received auto-HSCT after induction with Btz had significantly longer PFS than those without auto-HSCT (19 months vs 13 months, P=0.048). ⑤GEP analysis revealed that 1q21 amplification predominantly up-regulated expression of >50% genes within 1q21 region, and also altered expression of 28% genes in chromosome 1 and 10% genes in whole genome, particularly related to DNA repair and cell cycle. Conclusions: 1q is an independent adverse prognostic factor in patients with newly diagnosed MM. It is often associated with 1p deletion and IGH rearrangement. Patients with 1q respond well to Btz-based regimen, but they fail to gain long-term benefit from this treatment itself. However, auto-HSCT following Btz induction might improve survival of patients with 1q, suggesting a potential strategy to treat this high-risk subset of MM. GEP analysis warrants further attention in understanding the mechanisms underlying the high-risk of 1q.