HLA loci predisposing to immune TTP in Japanese: potential role of the shared ADAMTS13 peptide bound to different HLA-DR.

Immune-mediated thrombotic thrombocytopenic purpura (iTTP) is a rare autoimmune disorder caused by neutralizing anti-ADAMTS13 autoantibodies. In white individuals, HLA allele DRB1*11 is a predisposing factor for iTTP, whereas DRB1*04 is a protective factor. However, the role of HLA in Asians is unclear. In this study, we analyzed 10 HLA loci using next-generation sequencing in 52 Japanese patients with iTTP, and the allele frequency in the iTTP group was compared with that in a Japanese control group. We identified the following HLA alleles as predisposing factors for iTTP in the Japanese population: DRB1*08:03 (odds ratio [OR], 3.06; corrected P [Pc] = .005), DRB3/4/5*blank (OR, 2.3; Pc = .007), DQA1*01:03 (OR, 2.25; Pc = .006), and DQB1*06:01 (OR,: 2.41; Pc = .003). The estimated haplotype consisting of these 4 alleles was significantly more frequent in the iTTP group than in the control group (30.8% vs 6.0%; Pc < .001). DRB1*15:01 and DRB5*01:01 were weak protective factors for iTTP (OR, 0.23; Pc = .076; and OR, 0.23, Pc = .034, respectively). On the other hand, DRB1*11 and DRB1*04 were not associated with iTTP in the Japanese. These findings indicated that predisposing and protective factors for iTTP differ between Japanese and white individuals. HLA-DR molecules encoded by DRB1*08:03 and DRB1*11:01 have different peptide-binding motifs, but interestingly, bound to the shared ADAMTS13 peptide in an in silico prediction model.

Outcome of stem cell transplantation for Waldenström's macroglobulinemia: analysis of the Japan Society for Hematopoietic Cell Transplantation (JSHCT) Lymphoma Working Group.

The role of stem cell transplantation (SCT) for patients with Waldenström's macroglobulinemia (WM) remains undetermined. Therefore, we retrospectively evaluated the outcome of autologous and allogeneic SCT for patients with WM using the registry database of the Japan Society for Hematopoietic Cell Transplantation. Forty-six patients receiving autologous and 31 receiving allogeneic SCT were analyzed. The allogeneic SCT group included more patients with advanced disease status at transplant and received more lines of chemotherapy. The cumulative incidences of non-relapse mortality (NRM) at 1 year were 30.0% (95% CI, 14.7-46.9%) in the allogeneic SCT and 0% in the autologous SCT group. The estimated 3-year overall (OS) and progression-free (PFS) survival rates were 84.5% (95% CI, 66.0-93.4%) and 70.8% (95% CI, 53.0-82.9%) in the autologous SCT group, and 52.2% (95% CI, 32.5-68.6%) and 45.0% (95% CI, 26.3-62.0%) in the allogeneic SCT group. No patients died after the first 2 years following allogeneic SCT. In univariate analyses, disease status at SCT was significantly associated with PFS in autologous SCT, and with OS and PFS in allogeneic SCT. These results suggest that both autologous and allogeneic SCT have each potential role in WM. Allogeneic SCT is more curative for WM, but is associated with high NRM.

Influence of HLA 1-3-locus mismatch and antithymocyte globulin administration in unrelated bone marrow transplantation.

For patients without an HLA-matched donor, an HLA-mismatched unrelated donor (MMUD) has been considered as an alternative donor in allogeneic hematopoietic cell transplantation (allo-HCT). We conducted a nationwide retrospective study to compare the transplant outcomes among 1-, 2-, and 3-locus (allele/antigen) mismatched unrelated donors (1MMUD n = 2044, 2MMUD n = 492, and 3MMUD n = 73) in allo-HCT and to assess the impact of antithymocyte globulin (ATG) in allo-HCT from 1-3MMUD. 2MMUD and 3MMUD were independent significant adverse factors for grade III-IV acute graft-versus-host disease (GVHD) (hazard ratio [HR] 1.72, p < 0.001 and HR 2.48, p < 0.001), non-relapse mortality (NRM) (HR 1.47, p < 0.001 and HR 2.00, p < 0.001), and overall survival (OS) (HR 1.21, p = 0.0066 and HR 1.60, p = 0.0015). Conversely, the use of ATG was an independent favorable factor for grade III-IV acute GVHD (HR 0.43, p < 0.001), NRM (HR 0.51, p < 0.001), and OS (HR 0.74, p = 0.0012). On the other hand, HLA compatibility and the use of ATG were not associated with a risk of relapse. An interaction test between the number of HLA mismatches and the use of ATG revealed that the effect of ATG on NRM and OS in the 2MMUD group was significantly less than that in the 1MMUD group (HR 1.53, p = 0.036 and HR 2.34, p = 0.0046). This study indicated that the number of HLA mismatches and the use of ATG were significantly associated with not only GVHD, but also NRM and OS. Whereas the use of ATG could improve transplant outcomes in allo-HCT from 1MMUD, its effectiveness with 2MMUD and 3MMUD was limited.

Comparison of HLA Allele Mismatch and Antigen Mismatch in Unrelated Bone Marrow Transplantation in Patients with Leukemia.

We compared the effect of HLA single-antigen and single-allele mismatched unrelated bone marrow transplantation (UBMT) without in vivo/ex vivo T cell depletion. Becasue a single DRB1 mismatch is preferred among 1-allele or 1-antigen mismatched donors, we performed mismatched allele- or antigen-specific analyses with a single DRB1 mismatch as the reference. In adjusted comparison by multivariate analyses, an HLA-DRB1 single-allele mismatch resulted in a decreased risk of nonrelapse mortality (NRM; relative risk [RR], 1.33; 95% confidence interval [CI], 1.08 to 1.63, P = .006) compared with an HLA-DR single-antigen mismatch and conferred a decreased risk of NRM (RR, 1.25; 95% CI, 1.01 to 1.57; P = .025) and overall mortality (RR, 1.16; 95% CI, 1.00 to 1.37; P = .046) compared with an HLA-C single-antigen mismatch. Relative to an HLA-DRB1 single-allele mismatch, 2-mismatch transplants, including those with 1 or more antigen mismatches, resulted in a significantly increased risk of NRM (1-antigen/1-allele mismatch: RR, 1.68; 95% CI, 1.03 to 2.05; P < .001; 2-antigen mismatch: RR, 1.58; 95% CI, 1.04 to 2.02; P = .001) and overall mortality (1-antigen/1-allele mismatch: RR, 1.27; 95% CI, 1.09 to 1.47; P = .002; 2-antigen mismatch: RR, 1.27; 95% CI, 1.03 to 1.57; P = .02). NRM correlated with the combined number of mismatches and allele or antigen mismatches, with rates of 22%, 27%, 32%, 31%, and 38% at 4years for full match, single-allele mismatch, single-antigen mismatch, 2-allele mismatch, and 2 mismatches that included an antigen mismatch, respectively. Our results support the preference for an allele mismatch rather than an antigen mismatch in unrelated bone marrow donors with 1 DR mismatch or 2 mismatches for T cell-replete UBMT.

Hematopoietic Cell Transplantation for Acute Panmyelosis with Myelofibrosis: A Retrospective Study in Japan.

Acute panmyelosis with myelofibrosis (APMF) is a rare subtype of acute myeloid leukemia characterized by acute onset of cytopenias and bone marrow fibrosis in the absence of splenomegaly. Because the prognosis of APMF is extremely poor even after chemotherapy, hematopoietic cell transplantation (HCT) has been used to treat APMF. However, the outcome after HCT for APMF remains unclear. To evaluate the outcomes and prognostic factors after HCT as a therapeutic modality for APMF, we retrospectively analyzed the Japanese registration data of 40 APMF patients who received allogeneic and syngeneic HCT between 2005 and 2015. The median age at HCT was 53.5 years (range, 16 to 70). The disease status at HCT was first complete remission (CR1) in 13 patients (33%). The probability of overall survival and the cumulative incidence of relapse at 3 years were 24% and 59%, respectively. Univariate analysis identified that female sex and disease status CR1 at the time of HCT were significantly associated with higher overall survival. Although APMF patients have a poor long-term prognosis even after syngeneic and allogeneic HCT, these data suggested that allogeneic HCT offered a curative option for APMF.

Risk Stratification and Prognosticators of Acute Myeloid Leukemia with Myelodysplasia-Related Changes in Patients Undergoing Allogeneic Stem Cell Transplantation: A Retrospective Study of the Adult Acute Myeloid Leukemia Working Group of the Japan Society for Hematopoietic Cell Transplantation.

Although the prognosis of acute myeloid leukemia with myelodysplasia-related changes (AML-MRC) is worse than that of AML not otherwise specified (AML-NOS), transplantation outcomes and prognosticators of AML-MRC patients undergoing allogeneic stem cell transplantation (allo-SCT) remain unclear. Transplantation outcomes of AML-MRC (n = 4091) were compared with those of AML-NOS (n = 3964) in patients who underwent allo-SCT between 2003 and 2016 using a nationwide registration database. The 3-year overall survival (OS; 35.5% versus 50.6%) was lower and the relapse (42.3% versus 32.1%) and nonrelapse mortality (26.3% versus 22.0%) rates were higher in the AML-MRC group than in the AML-NOS group. Based on the hierarchical AML-MRC classification, myelodysplasia as the sole criterion was associated with better OS compared with AML-NOS, whereas monosomal or complex karyotype and -5/del(5q) were associated with poor OS. A history of myelodysplastic syndrome and -7/del(7q) did not affect OS. Accordingly, AML-MRC with complex karyotype or -5/del(5q) and that with monosomal karyotype were classified as intermediate and high risks, respectively, whereas the remaining cases were classified as low risk. The 3-year OS rates were 50.7%, 36.9%, and 13.8% in the low-, intermediate-, and high-risk groups, respectively (P < .001). Risk classification, older age, and low performance status score were significant risk factors for survival in AML-MRC, independently of the disease status. Grades I to II acute graft-versus-host disease significantly reduced the 3-year relapse (24.7% versus 31.6%), leading to better survival (hazard ratio, .64). Our prognostic risk stratification can potentially aid in elucidating the diverse transplantation outcomes in patients with AML-MRC.

Outcomes of second allogeneic haematopoietic stem cell transplantation in patients with relapse of myelodysplastic syndrome.

Though second allogenic haematopoietic stem cell transplantation (HSCT) is considered a curative treatment option after myelodysplastic syndrome (MDS) relapse, scant epidemiological data are available. We investigated the outcomes and prognostic factors of second allogenic HSCT in 99 patients with MDS who relapsed after the first HSCT. The median age was 53 years (interquartile; 45-59) and 57 patients (57·6%) were male. Five-year overall survival was 25·3%. Early relapse (adjusted hazard ratio: 2·78, 95% confidence interval: 1·08-7·21, P = 0·035) and poor performance (3·03, 1·71-5·37, P < 0·001) were associated with a significantly poor 5-year overall survival compared to the other groups (P < 0·001).

Increased opportunity for prolonged survival after allogeneic hematopoietic stem cell transplantation in patients aged 60-69 years with myelodysplastic syndrome.

We conducted a nationwide retrospective study to evaluate the outcomes of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in 651 patients aged 60-69 years with de novo myelodysplastic syndrome (MDS). We divided patients into two groups: 152 and 499 patients with an early and advanced disease status, respectively. The 3-year overall survival (OS) rate of patients with an early disease status was 45.9% (95% confidence interval [CI], 37.0 to 54.2%). A multivariate analysis revealed five adverse factors for OS: performance status (PS) 2-4 (hazard ratio [HR] 4.48; P < .001), poor cytogenetic risk group (HR 1.83; P = .041), male recipient (HR 2.58; P = .003), use of HLA-mismatched related grafts (HR 4.75; P = .003), and unrelated cord blood (HR 2.47; P = .023). The 3-year OS rate of patients with an advanced disease status was 37.2% (95% CI 32.4 to 41.9%). Five factors correlated with worse OS: PS 2-4 (HR 1.72; P = .003), poor cytogenetic risk group (HR 1.49; P = .003), use of HLA-mismatched related grafts (HR 1.96; P = .015), unrelated cord blood (HR 2.05; P < .001), and the high number of red blood cell transfusions before transplantation (HR 1.85; P = .018). The present results revealed the more frequent utilization of allo-HSCT for MDS patients aged 60-69 years, which increases the curative potential.

The effectiveness of busulfan-based conditioning regimens for stem cell transplantation against lymphomas in children, adolescents, and young adults in Japan.

Conditioning regimens for stem cell transplantation (SCT) involving total body irradiation (TBI) are generally preferred over busulfan (BU)-based ones for lymphoid malignancies. However, reports of favorable results using BU against lymphomas have recently emerged. This study sought to compare the effectiveness of BU and TBI regimens for SCT against lymphomas. We retrospectively analyzed 893 lymphoma patients who underwent primary SCT in Japan between 1980 and 2015. The median age of all patients was 18 years (range, 0-30 years) with 589 males, 303 females, and 1 patient whose sex was unknown. Overall survival (OS) was not different between those receiving BU and TBI (P = 0.672). OS in patients receiving autologous SCT was significantly better with BU over TBI regimens (P = 0.038), particularly in children (0-15 years) (P = 0.024). Conversely, OS in adolescents and young adults (AYAs; 16-30 years) receiving allogeneic SCT was significantly worse with BU over TBI regimens (P = 0.035). Overall, BU regiments had comparable effectiveness to TBI conditioning regimens, and, although less effective for AYAs with allogeneic SCT, were particularly more effective than TBI regimens for children who received autologous SCT.

[Cytomegalovirus infections following allogeneic hematopoietic stem cell transplantation: prophylaxis and treatment].

In patients who undergo hematopoietic stem cell transplantation (HSCT), cytomegalovirus (CMV) infection directly or indirectly increases all-cause and non-relapse mortality rates. Although preemptive therapy suppresses CMV infection, it does not improve non-relapse mortality rates in patients with CMV reactivation compared to patients with no CMV reactivation. According to the World Health Organization International Standards (WHO IS), quantitative polymerase chain reaction has been recently adopted as the global standard for monitoring CMV, and maribavir, brincidofovir, and letermovir have been developed as new antiviral drugs for the treatment of CMV infection. Letermovir, a first-class anti-CMV agent, strongly inhibits the CMV DNA terminase complex, which is required for viral DNA cleavage and packaging. It significantly suppressed CMV infection in a phase III clinical trial, thereby improving the overall survival of patients who undergo HSCT. Vaccines and cell therapies for CMV must be further developed.

Prognostic Impact of Donor Source on Allogeneic Hematopoietic Stem Cell Transplantation Outcomes in Adults with Chronic Myelomonocytic Leukemia: A Nationwide Retrospective Analysis in Japan.

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a curative therapeutic option for patients with chronic myelomonocytic leukemia (CMML). We retrospectively compared the post-transplantation outcomes of 159 patients with CMML who underwent allo-HSCT using 4 types of donor sources: HLA-matched related donor graft, unrelated bone marrow (U-BM), unrelated cord blood (U-CB), and HLA-mismatched related donor graft. The median patient age at allo-HSCT was 54 years (range, 16 to 75 years). In multivariate analyses, the use of HLA-matched related donor grafts correlated with better overall survival than U-BM (hazard ratio [HR], 2.05; 95% confidence interval [CI], 1.21 to 3.48; P = .008), U-CB (HR, 3.80; 95% CI, 2.07 to 6.95; P < .001), or HLA-mismatched related donor grafts (HR, 6.18; 95% CI, 2.70 to 14.15; P < .001). Mortality after the relapse or progression of CMML did not significantly differ among the 4 types of donor source. Transplantation-related mortality was highest in recipients of U-CB (HR, 3.32; 95% CI, 1.33 to 8.26; P = .010). In patients with CMML, allo-HSCT using an alternative donor may contribute to durable remission; however, further improvements in transplantation-related mortality are required for this type of transplantation.

Impact of HIV Infection on Transplant Outcomes after Autologous Peripheral Blood Stem Cell Transplantation: A Retrospective Study of Japanese Registry Data.

Autologous stem cell transplantation (ASCT) is a treatment option for HIV-positive patients with non-Hodgkin lymphoma (NHL) and multiple myeloma (MM). However, the prognosis after ASCT in HIV-positive Japanese patients remains unclear. The aim of this study was to evaluate the impact of HIV infection on transplant outcomes after ASCT in Japan. Using the national database of the Japan Society for Hematopoietic Cell Transplantation, we retrospectively evaluated patients with NHL (n = 3862) and MM (n = 2670) who underwent their first ASCT between 2001 and 2014. The presence of HIV antibody was used to diagnose HIV infection. Fifty-six patients with NHL (1.4%) and 23 with MM (.8%) were positive for HIV antibody. Among patients with NHL overall survival (OS) was lower in HIV-positive patients than in HIV-negative patients (5-year OS: HIV-positive patients, 44% versus HIV-negative patients, 65%; P < .001). In a multivariate analysis HIV infection was significantly associated with an increased risk of overall mortality (hazard ratio, 2.30; P < .001). The incidence of relapse was higher in HIV-positive patients (P = .036), whereas there was a similar incidence of nonrelapse mortality (P = .879). OS in patients with MM was similar between those with/without HIV infection (5-year OS: HIV-positive patients, 61% versus HIV-negative patients, 63%; P = .988). HIV infection was associated with a higher risk of overall mortality and relapse after ASCT for NHL in a Japanese population.

Improved prognosis with additional medium-dose VP16 to CY/TBI in allogeneic transplantation for high risk ALL in adults.

Allogeneic hematopoietic stem cell transplantation (HSCT) with the conventional cyclophosphamide and total body irradiation (CY/TBI) regimen is an essential therapeutic strategy for acute lymphoblastic leukemia (ALL) in adults. Medium-dose etoposide (VP16, 30-40 mg/kg) can be added to intensify this CY/TBI regimen and reduce relapse; however, differences in prognosis between the VP16/CY/TBI and CY/TBI regimens have not yet been fully analyzed. We conducted a retrospective cohort study using a Japanese transplant registry database to compare the prognosis between the VP16/CY/TBI (VP16, total 30-40 mg/kg) (N = 376) and CY/TBI (N = 1178) regimens in adult patients with ALL transplanted at complete remission (CR) between January 1, 2000 and December 31, 2014. Our analyses indicated that VP16/CY/TBI significantly reduced relapse compared with CY/TBI (risk ratio, 0.75; 95% confidence interval [CI], 0.56-1.00; P = .05) with a corresponding improvement in leukemia-free survival (hazard ratio [HR], 0.76; 95%CI, 0.62-0.93; P = .01), particularly in patients transplanted at CR1 with advanced-risk (positive minimal residual disease, presence of poor-risk cytogenetics, or an initial elevated leukocyte count) (HR, 0.75; 95%CI, 0.56-1.00; P = .05) or those transplanted beyond CR2 (HR, 0.58; 95%CI, 0.39-0.88; P = .01). The addition of VP16 did not increase post-transplant complications or nonrelapse mortality (HR, 0.88; 95%CI, 0.65-1.18; P = .38). This study is the first to reveal the efficacy of the addition of medium-dose VP16 to CY/TBI in high-risk ALL. To establish new myeloablative conditioning regimens including VP16, a large-scale prospective study is necessary.

Significance of Salvage Autologous Stem Cell Transplantation for Relapsed Multiple Myeloma: A Nationwide Retrospective Study in Japan.

Autologous stem cell transplantation (ASCT) has been employed for patients with relapsed multiple myeloma (MM) after up-front ASCT. The present retrospective study aimed to examine the survival benefit from salvage ASCT. Among 446 patients with relapsed MM after up-front single ASCT, 70 patients received salvage ASCT, the employment of which reduced the risk of mortality after relapse (p = 0.041). Using the parameters before initial ASCT, the advantage of salvage ASCT compared to standard therapy was confirmed in the subgroup with an international staging system stage of I or II (p = 0.040), good performance status (PS; p = 0.043), or no/mild renal comorbidity (p = 0.029). The advantage of salvage ASCT was also confirmed in the subgroup excluding those with early relapse within 7 months after initial ASCT (p = 0.026). Among patients who received salvage ASCT, a favorable prognosis is apparent for those with a time to relapse after initial ASCT of longer than 24 months. The overall survival after salvage ASCT was favorable excluding patients with the following factors: early relapse, poor PS, moderate/severe renal comorbidity, and progressive disease (p < 0.001). In conclusion, our results reinforced the evidence for encouraging salvage ASCT for eligible patients.

[Acute leukemia recurring as extramedullary tumors of the ovary following allogeneic hematopoietic stem cell transplantation].

The poor prognosis of extramedullary recurrence of acute leukemia following allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a therapeutic challenge, and thus far no effective treatment method has been established. Here, we report two patients who presented with relapsed leukemia as extramedullary tumor in the ovary following allo-HSCT. Case 1: A 23-year-old female underwent unrelated allogeneic bone marrow transplantation during the second remission of acute myeloid leukemia. After 706 days post-transplant, bilateral ovarian tumors were detected during the pelvic ultrasound, and extramedullary recurrence in the bilateral ovaries was subsequently established on right salpingo-oophorectomy and biopsy of the left ovary. Following completed systemic chemotherapy and total body irradiation, the patient underwent unrelated cord blood transplantation (CBT) and remission was maintained without recurrence for 7 years after second transplantation. Case 2: A 49-year-old female underwent unrelated CBT during the second remission of acute lymphocytic leukemia. At 372 days post-transplant, a pelvic tumor was detected by FDG-PET/CT, and extramedullary recurrence in the right ovary was diagnosed on examination of the resected pelvic mass. Chemotherapy and radiation were performed, but the tumor recurred on day 1,027 and the patient died on day 1,603. Extramedullary recurrence of adult acute leukemia as a mass in the ovary following allo-HSCT has been rarely reported. Therefore, further accumulation of related case reports is desired.

Outcomes of Allogeneic Hematopoietic Stem Cell Transplantation in Adult Patients with Myelodysplastic Syndrome Harboring Trisomy 8.

Trisomy 8 (+8) is 1 of the most common cytogenetic abnormalities in adult patients with myelodysplastic syndrome (MDS). However, the outcome of allogeneic hematopoietic stem cell transplantation (HSCT) in adult patients with MDS harboring +8 remains unclear. To evaluate the outcome and prognostic factors in patients with MDS harboring +8 as the sole cytogenetic abnormality or in association with other abnormalities, we retrospectively analyzed the Japanese registration data of 381 adult patients with MDS harboring +8 treated with allogeneic HSCT between 1990 and 2013. With a median follow-up period of 53 months, the probability of overall survival and cumulative incidence of relapse at 4 years were 51% and 22%, respectively. In the multivariate analysis, age > 50 years, 2 or more additional cytogenetic abnormalities, and a high risk at the time of HSCT according to the FAB/WHO classification were significantly associated with a higher overall mortality. Nevertheless, no significant impact of the outcome was observed in patients with 1 cytogenetic abnormality in addition to +8. Although 221 patients (58%) had advanced MDS at the time of HSCT, allogeneic HSCT offered a curative option for adult patients with MDS harboring +8.

Impact of Human Leukocyte Antigen Allele Mismatch in Unrelated Bone Marrow Transplantation with Reduced-Intensity Conditioning Regimen.

The impact of HLA mismatch in hematopoietic stem cell transplantation with reduced-intensity conditioning (RIC) has not been fully examined. We analyzed a total of 1130 cases to examine the effects of HLA allele mismatch in unrelated bone marrow transplantation (BMT) with RIC in the Japan Marrow Donor Program registry cohort. Compared with HLA 8/8-allele match (n = 720, 8/8 match), both 1 (n = 295, 7/8 match) and 2 allele mismatches (n = 115, 6/8 match) were associated with significant reduction of overall survival (OS) (hazard ratio [HR], 1.34; P = .0024 and HR, 1.33; P = .035 for 7/8 and 6/8 match, respectively). The incidence of grades 2 to 4 acute graft-versus-host disease (aGVHD) increased with increasing number of mismatched alleles (HR, 1.36 and HR, 2.08 for 7/8 and 6/8 match, respectively). Nonrelapse mortality showed a similar tendency to aGVHD (HR, 1.35 for 7/8 and HR, 1.63 for 6/8). One-allele mismatches at the HLA-A or -B and HLA-C loci were significantly associated with inferior OS compared with 8/8 match (HR, 1.64 for A or B mismatch and HR, 1.41 for C mismatch), whereas HLA-DRB1 allele mismatch was not (HR, 1.16; P = .30). However, the effect of HLA-A or -B and -C mismatch on OS was not observed in those who received RIC BMT since 2010, in contrast to recipients before 2010. These results suggested that in unrelated RIC BMT, 1-allele mismatch is associated with poorer outcome, and the impact of HLA mismatch may differ depending on the HLA locus, although these HLA mismatch effects may be different in recent cases.

Comparison of Conditioning with Fludarabine/Busulfan and Fludarabine/Melphalan in Allogeneic Transplantation Recipients 50 Years or Older.

The optimal conditioning regimen for elderly patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HCT) remains unclear. We retrospectively analyzed 1607 patients aged 50 years or older with acute myeloid leukemia (AML), acute lymphoblastic leukemia, or myelodysplastic syndrome (MDS) who underwent allo-HCT using fludarabine/busulfan (FB) or fludarabine/melphalan (FM) between 2007 and 2014. We compared the clinical outcomes among FB2 (busulfan at 6.4 mg/kg iv, n = 463), FB4 (busulfan at 12.8 mg/kg iv, n = 721), and FM140 (melphalan at 140 mg/m2, n = 423). The nonrelapse mortality (NRM) rates in the FB4 and FM140 groups were higher than that in the FB2 group (hazard ratio [HR], 1.63 [P < .001]; and HR, 1.71 [P < .001], respectively). Conversely, the relapse rates in the FB4 and FM140 groups were lower than that in the FB2 group (HR, .73 [P = .011]; and HR, .56 [P < .001], respectively). There were no significant differences in overall survival (OS) among the FB2, FB4, and FM140 groups. The 3-year OS in patients with high-risk AML and MDS in the FM140 group (37.0% and 60.2%) were superior to those in the FB2 group (24.4% and 45.5%) and the FB4 group (24.6% and 40.6%) (P = .016 and P = .023), whereas there were no differences in OS in the other patients among the 3 groups. In conclusion, the lower rates of relapse in the FB4 and FM140 groups were largely offset by a worse NRM. However, FM140 might be associated with better OS in patients with high-risk AML and MDS.

Role of reduced-intensity conditioning allogeneic hematopoietic cell transplantation in older patients with de novo acute myeloid leukemia.

Reduced-intensity conditioning (RIC) regimens extend the therapeutic use of allogeneic hematopoietic cell transplantation (HCT) to older patients. The survival trend in 2325 patients aged >50 years presenting with de novo acute myeloid leukemia (AML) who underwent first reduced-intensity HCT (RIC-HCT) was assessed by retrospectively analyzing outcomes between 2000 and 2013. The annual number of RIC-HCTs in Japan was higher in the 2008-2013 period (n = 205/year [1229/6 years]) than in the 2000-2007 period (n = 137/year [1096/8 years]). Overall and disease-free survival were higher in the 2008-2013 period (P < 0.001) because of the improvement in transplant-related mortality (TRM). Survival regarding RIC-HCT for AML has improved over time, with an increased number of RIC-HCTs in patients with a Karnofsky performance status (KPS) ≥80. However, TRM remains high and the relapse rate has not improved over time. Multivariate analyses showed that a KPS ≥80 and complete remission at HCT were associated with less TRM and relapse, and better survival regardless of age ≥65 years. Accurate timing and prospective identification of patients at risk of TRM may aid the development of risk-adapted strategies for RIC-HCT in AML patients regardless of age.

[Philadelphia chromosome-positive acute lymphoblastic leukemia complicated by concomitant Achromobacter xylosoxidans and Corynebacterium striatum bacteremia following allogeneic hematopoietic stem cell transplantation].

A 54-year-old woman with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) underwent hematopoietic stem cell transplantation from an HLA-matched sibling. Subsequently, she suffered from chronic graft versus host disease (GvHD) and received medical treatment. Fever developed on day 697 and resulted in a shock state at 10 h after the visit. Achromobacter xylosoxidans was detected in the initial blood culture on day 699. General conditions exacerbated even after the start of meropenem hydrate (MEPM, Meropen®) administration, with Corynebacterium striatum detected as an additional species in the initial blood culture on day 701. Although vancomycin hydrochloride (VCM, Vancomycin®) was administered, the conditions did not improve. She died on day 702. Between January 2012 and December 2016, A. xylosoxidans was detected only in nine cases in our hospital, which included five with hematological malignancies and only one (present) with sepsis. At the same time, Corynebacterium species were detected in blood cultures from 39 cases in our hospital, which included 31 with hematological malignancies. Some reports on drug-resistant A. xylosoxidans and C. striatum have been published. Infections with these species may become fatal when complicated by sepsis in immunocompromised patients with hematological malignancies. More cases should be accumulated for detailed investigation.