Minimal residual disease detection in multiple myeloma: comparison between BML single-tube 10-color multiparameter flow cytometry and EuroFlow multiparameter flow cytometry.

Minimal residual disease (MRD)-negative status in multiple myeloma (MM) is associated with favorable outcomes. Although EuroFlow next-generation flow (NGF) is a global standard for MRD detection, its operating cost is high. Therefore, it is desirable to develop a less expensive method with equivalent sensitivity to that of EuroFlow-NGF. In this study, we compared the analytical ability of our BML 10-color multiparameter flow cytometry (MFC) to that of EuroFlow-NGF. Bone marrow samples collected from 51 patients with MM were subjected to MRD detection using BML 10-color-MFC and EuroFlow-NGF. Our antibody panel consisted of CD38 multiepitope, CD138, CD45, CD56, CD19, CD27, CD81, CD117, cytoplasmic immunoglobulin (cIg) κ, and cIgλ in a single tube. The median percentages of total plasma cells, as per 10-color-MFC and EuroFlow-NGF, were 0.2148% and 0.2200%, respectively, with a good correlation between the methods (r = 0.950). The median percentages of myeloma cells determined via 10-color-MFC and EuroFlow-NGF were 0.0012% and 0.0007%, respectively, with a strong correlation (r = 0.954). Our 10-color-MFC demonstrated high sensitivity to detect MRD; the results showed a good correlation with those obtained using EuroFlow-NGF. Therefore, our cost-effective single-tube MFC (approximately 100 USD/sample) is a promising alternative method for the detection of MRD in patients with MM.

[Cost-effectiveness of peripheral blood stem cell collection using plerixafor: a single-center study].

Plerixafor is increasingly used in combination with granulocyte-colony-stimulating factor (G-CSF) for peripheral blood stem cell collection. Although it is an expensive drug, its cost-benefit performance is not well investigated. Thus, we analyzed its cost-effectiveness in our hospital. A retrospective observational analysis was performed in patients who underwent stem cell collection between December 2013 and November 2018. A total of 203 patients were investigated and classified into three groups according to their pre-mobilization regimen: G-CSF alone, G-CSF and cyclophosphamide (G+CY), and G-CSF and plerixafor (G+plerixafor). The cost-effectiveness of apheresis of the collected cluster of differentiation (CD) 34+ cells was assessed based on two viewpoints: cost of drugs and cost of equipment. Due to the high cost of plerixafor, the cost of apheresis was higher in patients who received G+plerixafor. However, the difference narrowed when we calculated the cost to collect 2.0×106 CD34+ cells/kg body weight required for a single transplant. The number of stem cells collected from patients who received G+plerixafor was higher than those who received other regimens (median CD34+ cells harvested/day were 2.90 for G-CSF, 2.13 for G+CY, and 4.63 for G+plerixafor, ×106/kg body weight, P<0.01). Our results show that plerixafor enables efficient apheresis.

The efficacy and safety of modified bortezomib-lenalidomide-dexamethasone in transplant-eligible patients with newly diagnosed multiple myeloma.

OBJECTIVES: Bortezomib with lenalidomide and dexamethasone (VRd) is a standard induction regimen for transplant-eligible patients with newly diagnosed multiple myeloma (NDMM). However, some patients discontinue VRd because of severe adverse events, despite its high efficacy. We aimed to study the efficacy of modified dose of VRd (VRd lite) in transplant-eligible patients with NDMM. METHODS: Forty-eight transplant-eligible patients with NDMM were included. VRd lite was administered every 4 weeks. Bortezomib 1.3 mg/m2 was administered subcutaneously on days 1, 8, 15 and 22, and dexamethasone 20 mg was administered orally on the day of and the day after bortezomib administration. Lenalidomide was omitted on days 1, 8 and 15, which are the days of bortezomib administration. RESULTS: The overall response rate (ORR) after four cycles of VRd lite was 83%, including a complete response of 25%. Thirty-eight among the 45 patients who completed at least four cycles of VRd lite received autologous stem cell transplantation (ASCT). The ORR and very good partial response or better were upgraded to 100% and 74%, respectively, following ASCT. CONCLUSION: Our strategy consisting of VRd lite followed by ASCT is, thus, a highly effective and well-tolerated regimen resulting in durable responses in patients with NDMM.

[Clinical characteristics of young multiple myeloma patients: a single-center analysis of 30 patients].

Because multiple myeloma is rare in young people, there are fewer reports on the same. Thus, its clinical aspects and prognosis remain unelucidated. We retrospectively evaluated 30 patients with multiple myeloma aged ≤ 45 years at diagnosis. We divided them into three groups based on their cytogenetic risks: standard risk (SR), high risk (HR), and unknown risk. The frequency of HR patients was 36.6%, the highest of the three groups, unlike the previous report. The median progression-free survival (PFS) was 35 months (SR vs. HR, 46 vs. 29 months), and the median overall survival (OS) was not reached (NR) (SR vs. HR, NR vs. 82 months). The OS was significantly worse, and the PFS also appeared inferior in HR patients. The International Staging System score was not associated with OS. Thus, young patients with myeloma appeared to have a higher frequency of HR features, suggesting that instead of age, the cytogenetic risk was a significant prognostic factor.

Red blood cell distribution width is a simple and novel biomarker for survival in light-chain amyloidosis.

Red blood cell distribution width (RDW) has been used for the differential diagnosis of anemia, but high RDW may also be associated with several human disorders. We evaluated the prognostic relevance of RDW in patients with light-chain (AL) amyloidosis. We retrospectively analyzed all patients with AL amyloidosis who were newly diagnosed at the Japanese Red Cross Medical Center between December 2011 and June 2018. RDW was evaluated in 94 patients; 48% (n = 45) of patients had a high RDW (≥ 13.8%) and 52% (n = 49) had a low RDW (< 13.8%). Overall survival (OS) was significantly lower in patients with a high RDW (P < 0.001). On multivariate analysis, increased RDW was an independent predictor for OS. Even in patients without cardiac amyloidosis, the OS was significantly lower in the high-RDW group (P = 0.0064). The survival rate of high-RDW patients without cardiac involvement was as poor as that of patients with cardiac involvement. In addition, in patients with revised Mayo stage I or a normal level of N-terminal pro-B-type natriuretic peptide, high RDW was negatively correlated with OS (P = 0.0086, 0.025). RDW is a simple and strong predictor of early death, and is a prognostic biomarker in patients with AL amyloidosis without cardiac involvement.

[Efficacy of plerixafor in autologous peripheral blood stem cell collection].

Failure of autologous peripheral blood stem cell collection (PBSCH) can affect the treatment modality for patients with hematological malignancies. The clinical efficacy of plerixafor in PBSCH was analyzed in our institution. The medical records of 61 patients were retrospectively reviewed. The use of plerixafor was determined according to the CD34+ cell count in the peripheral blood (PB CD34+) on day 4 of G-CSF administration and patients' backgrounds. A total of 47 patients received G-CSF plus plerixafor: 31 with multiple myeloma, 8 with AL amyloidosis or POEMS syndrome, and 8 with non-Hodgkin lymphoma. The median fold increase in PB CD34+ following the first dose of plerixafor was 7.18 times. The median number of collected CD34+ cells on day 5 was 4.1×106/kg and 5.3×106/kg in total. Among the 47 patients, 44 (93.6%) yielded the minimum required cell collection of 2.0×106/kg within an average of 1.3 days. Plerixafor enables rapid and efficient mobilization, and sufficient numbers of CD34+ cells were successfully collected.

Frequent structural variations involving programmed death ligands in Epstein-Barr virus-associated lymphomas.

Viral infection induces potent cellular immunity and activated intracellular signaling, which may dictate the driver events involved in immune escape and clonal selection of virus-associated cancers, including Epstein-Barr virus (EBV)-positive lymphomas. Here, we thoroughly interrogated PD-L1/PD-L2-involving somatic aberrations in 384 samples from various lymphoma subtypes using high-throughput sequencing, particularly focusing on virus-associated lymphomas. A high frequency of PD-L1/PD-L2-involving genetic aberrations was observed in EBV-positive lymphomas [33 (22%) of 148 cases], including extranodal NK/T-cell lymphoma (ENKTL, 23%), aggressive NK-cell leukemia (57%), systemic EBV-positive T-cell lymphoproliferative disorder (17%) as well as EBV-positive diffuse large B-cell lymphoma (DLBCL, 19%) and peripheral T-cell lymphoma-not otherwise specified (15%). Predominantly causing a truncation of the 3'-untranslated region, these alterations represented the most prevalent somatic lesions in ENKTL. By contrast, the frequency was much lower in EBV-negative lymphomas regardless of histology type [12 (5%) of 236 cases]. Besides PD-L1/PD-L2 alterations, EBV-positive DLBCL exhibited a genetic profile distinct from EBV-negative one, characterized by frequent TET2 and DNMT3A mutations and the paucity of CD79B, MYD88, CDKN2A, and FAS alterations. Our findings illustrate unique genetic features of EBV-associated lymphomas, also suggesting a potential role of detecting PD-L1/PD-L2-involving lesions for these lymphomas to be effectively targeted by immune checkpoint blockade.

[Elotuzumab treatment for a multiple myeloma patient relapsing after allogenic stem cell transplantation].

Although elotuzumab (ELO) is associated with improved outcomes in patients with relapsed/refractory multiple myeloma (MM), no data are available for the usage of ELO following allogeneic stem cell transplantation (allo-SCT). Here, we report two cases of relapsed MM treated with ELO in combination with lenalidomide (LEN) and dexamethasone (ELd) following allo-SCT. Case 1 had been treated with 11 lines of therapy followed by cord blood transplantation resulting in partial response. ELd was introduced 140 days post-transplantation and continued for eight cycles until disease progression. No worsening in graft-versus-host disease (GvHD) was observed under ELd treatment. Case 2 had received unrelated bone marrow transplantation due to primary refractory disease after undergoing six regimens. Carfilzomib-based maintenance therapy had to be discontinued owing to severe myelosuppression. Subsequently, ELd treatment was initiated 544 days following the allo-SCT, which led to an improvement in serum paraprotein level and amelioration in GvHD. In both cases, immunosuppressants were tapered off. Several studies have shown exacerbation of GvHD under LEN monotherapy following allo-SCT. However, an ELd regimen may be one of the safer options for treating post-allo-SCT relapse.

[Carfilzomib, lenalidomide, and dexamethasone therapy for refractory and relapsed multiple myeloma: a single-center study of 29 patients].

Twenty-nine patients with multiple myeloma were treated with carfilzomib, lenalidomide, and dexamethasone (KLd) therapy. A response better than partial response (PR) was observed in 72.4% patients with relapsed and/or refractory myeloma. Although 13.8% patients developed hypertension, none of them discontinued therapy as they could be managed by appropriate medication. A patient who had an elevated level of BNP prior to initiating KLd therapy developed heart failure. Results from this study demonstrate that KLd therapy is efficacious for treating patients with multiple myeloma; however, they should be carefully monitored for cardiotoxicity.

[IgE-κ type multiple myeloma achieving complete response with novel agents].

IgE multiple myeloma (MM) is a rare subtype of MM characterized by an aggressive and poor prognosis. Although novel agents have improved the prognosis of MM, there are few case reports of IgE MM treated with these agents. A 53-year-old male patient presented with pain in the right rib and was diagnosed with IgE-κ MM. He was treated with multidrug chemotherapy, including bortezomib and lenalidomide, and underwent autologous stem-cell transplantation (ASCT). Finally, he achieved a complete response after the initiation of pomalidomide. In previous reports, majority of patients with refractory IgE MM treated with novel agents had a poor prognosis. In contrast, patients who were treated with novel agents from the beginning and underwent ASCT had a long-term survival. Overall, the use of novel agents as the first-line therapy is expected to improve IgE MM prognosis.

Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis during pregnancy.

An 11-week pregnant, 32-year-old Japanese woman who had recovered from infectious mononucleosis visited our center due to fever, anorexia, and bilateral hypochondrial pain. Blood tests revealed leukopenia, thrombocytopenia and elevated ferritin. She was diagnosed with hemophagocytic lymphohistiocytosis (HLH). A high viral load of the Epstein-Barr virus (EBV) was recognized, indicating EBV-HLH. She was treated with a single dose of dexamethasone to protect the fetus. However, the disease was uncontrollable, necessitating etoposide and cyclosporine administration. Remission was obtained with these medications, and she has remained in remission for the 10 months since completion of chemotherapy. Although the occurrence of EBV-HLH during pregnancy is rare, it is possible that a change in cellular immunity associated with the pregnancy may contribute to EBV-HLH development.

High-dose melphalan and autologous stem cell transplantation for systemic light-chain amyloidosis: a single institution retrospective analysis of 40 cases.

We report our retrospective analysis of 40 patients who received high-dose melphalan and autologous stem cell transplantation for systemic immunoglobulin light-chain (AL) amyloidosis. Between 2006 and 2013, 40 patients with AL amyloidosis were transplanted at our medical center. Their median age was 54 years (range 32-70 years): 18 were male. The dominant organs involved were the heart in 13 patients, and kidney in 22: and other organs were involved in five. The median melphalan dose administered was 129 (range 50-200) mg/m(2), and the median infused CD34(+) cells was 2.69 (range 1.17-11.26) × 10(6)/kg. Of the 40 patients, 30 are alive after a median follow-up of 42 (range 12-94) months, and the 4-year estimated overall survival rate was 74% (95% CI 56-86%). Four patients died ≤ 100 days post-ASCT (heart failure in three patients, bacteremia in one). The 4-year estimated survival of the patients with cardiac involvement was 54%, significantly lower than that of the other patients (91%). Hematological and organ responses were 52 and 50%, respectively. Careful patient selection and experienced management are important, especially for patients with cardiac involvement. It is also important to develop additional treatment for patients who do not achieve a hematological and/or organ response.

[Induction treatment with bortezomib-cyclophosphamide-dexamethasone (CyBorD) for newly diagnosed transplant-eligible patients with multiple myeloma].

Twenty-nine transplant eligible newly diagnosed multiple myeloma (NDMM) patients have received Cyclophosphamide-Bortezomib-Dexamethasone (CyBorD) as induction treatment in our institute since November 2011. CyBorD is composed of CPA 300 mg/m2 p.o., Bor 1.3 mg/m2 i.v. or s.c., and Dex 40 mg/body p.o. on days 1, 8, 15, and 22. The median number of CyBorD cycles was 4 (range 2-6), except in one patient who progressed during the first cycle. Grade 4 neutropenia was observed in 2 patients, but none experienced grade 2 thrombocytopenia. Grade 3 non-hematologic adverse events were observed in two patients with varicella-zoster virus reactivation. Responses after CyBorD were ≥PR in 72%, ≥VGPR in 52%, ≥CR in 21%, and sCR in 21%. Autologous stem cells were harvested in 27 patients. Seventeen of these 27 patients received high-dose melphalan and autologous stem cell transplantation (ASCT) within 12 months after diagnosis. Patients with ≥CR increased to 59% after ASCT. Our data suggest the efficacy and the feasibility of administering CyBorD to transplant eligible NDMM patients.

[Graft-versus-host disease associated with lenalidomide maintenance after allogeneic transplantation for relapsed/refractory multiple myeloma].

Although allogeneic stem cell transplantation (allo-SCT) is a potentially curative treatment option for multiple myeloma (MM), it is not recognized as a standard of care because of the high associated incidences of both treatment related mortality and relapse. We administered lenalidomide (Len) as maintenance therapy for patients with MM undergoing allo-SCT who were at high risk of disease relapse. Graft-versus-host disease was induced by Len administration in two patients, but was manageable with dose reduction. Although Len has a direct anti-myeloma effect and can also induce tumor immunity against residual myeloma cells, it is important to identify how to optimize the safety and the effects of Len administration after allo-SCT. Further accumulation of data including those from prospective clinical trials is urgently needed.

Survival of multiple myeloma patients aged 65-70 years in the era of novel agents and autologous stem cell transplantation. A multicenter retrospective collaborative study of the Japanese Society of Myeloma and the European Myeloma Network.

Novel agents such as thalidomide, lenalidomide and bortezomib have dramatically changed the treatment paradigm of multiple myeloma (MM). However, it is not clear whether these agents improve the prognosis of elderly patients who have undergone autologous stem cell transplantation (auto-SCT). We retrospectively analyzed the outcome of 318 newly diagnosed patients aged 65­70 years who were treated between January 1, 2004, and December 31, 2009. As initial therapy, 192 patients were treated with conventional chemotherapy,88 with novel agent-containing regimens, 21 with conventional chemotherapy plus auto-SCT and the remaining 17 with novel agents plus auto-SCT. The median progression-free survival was 19.1, 24.5, 26.8 and 35.2 months, respectively, and the 5-year overall survival (OS) was 40, 62, 63 and 87%, respectively. Initial therapy with novel agents (p < 0.001) or auto-SCT (p < 0.02) significantly improved OS compared with the group without these treatment modalities. Salvage therapy with novel agents also significantly improved survival after relapse compared with conventional chemotherapy alone (p < 0.04). In a multivariate analysis, the use of novel agents was an independent prognostic factor significantly associated with extended OS(p < 0.003). These results indicate that novel agents and auto-SCT had a major impact on OS in eligible patients in this subgroup of MM.

Moxifloxacin is more effective than tosufloxacin in reducing chemotherapy-induced febrile neutropenia in patients with hematological malignancies.

Recent studies have shown the prophylactic efficacy of fluoroquinolones against infections in patients with chemotherapy-induced neutropenia. However, little is known about the differences between fluoroquinolones, and there are some concerns about the emergence of resistant bacteria. In this retrospective study, we compared the prophylactic efficacy of moxifloxacin (MFLX) and tosufloxacin (TFLX) for chemotherapy-induced febrile neutropenia. The cumulative incidences of febrile neutropenia were 74.7% (59 of 79) in the MFLX group and 81.1% (219 of 270) in the TFLX group (log-rank test p = 0.044). Subgroup analysis revealed a more prominent prophylactic advantage of MFLX in patients with acute myeloid leukemia (AML) or long duration of neutropenia (p = 0.013 and 0.008, respectively). There were no significant differences in the incidences of adverse events and fluoroquinolone resistant bacteria in both groups. This study indicates that prophylaxis with MFLX is more beneficial to reduce febrile neutropenia episodes than TFLX, especially in patients with high-risk disease.

A case of myeloid sarcoma with correlation to JAK2V617F mutation, complicated by myelofibrosis and secondary acute myeloid leukemia.

The activating mutation of JAK2, V617F, has been found as a frequent mutation in myeloproliferative neoplasms (MPNs), including polycythemia vera (PV), essential thrombocytosis (ET), and primary myelofibrosis (PMF). This mutation is observed not only in MPNs, but also in chronic myelomonocytic leukemia, myelodysplastic syndrome and acute myeloid leukemia (AML). We report a case of myeloid sarcoma and myelofibrosis, followed by secondary AML, with detection of homozygous JAK2 V617F mutation. This report describes the first case of myeloid sarcoma with JAK2 V617F mutation and implication of its progression to AML.