[Kidney transplantation for end-stage renal disease after third allogeneic hematopoietic stem cell transplantation for Philadelphia chromosome-positive acute lymphoblastic leukemia].

An 18-year-old man underwent allogenic bone marrow transplantation (BMT) for Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL). Ph+ALL relapsed 3 months after the first BMT, and the patient underwent a second BMT. However, Ph+ALL relapsed 4 months after the second BMT, and he received a haploidentical peripheral blood stem cell transplantation (haplo-PBSCT) from his father. Molecular complete remission was confirmed 29 days after haplo-PBSCT. However, the patient needed dialysis for end-stage renal disease due to thrombotic microangiopathy 3 years and 2 months after haplo-PBSCT. He received a kidney transplantation from his father 7 years and 10 months after haplo-PBSCT, and got off dialysis after the kidney transplantation. Immunosuppressive therapy with methylprednisolone, tacrolimus, and mycophenolate mofetil was started for kidney transplantation, but the dose of immunosuppressive agents was reduced successfully without rejection soon after kidney transplantation. The patient has maintained long-term remission since the haplo-PBSCT, and his kidney function was restored by the kidney transplantation from his father.

[Polatuzumab vedotin, bendamustine, and rituximab in patients with relapsed/refractory diffuse large B-cell lymphoma, including the outcome as a bridging treatment to CAR-T cell therapy or allogeneic hematopoietic stem cell transplant].

Pola-BR (polatuzumab vedotin, bendamustine, and rituximab) therapy received approval for relapsed/refractory diffuse large B-cell lymphoma (R/R DLBCL) in Japan in March 2021. There have been few reports on the efficacy and safety of Pola-BR therapy in Japanese clinical practice. A retrospective analysis was performed on twenty-nine patients with R/R DLBCL who received Pola-BR therapy at our institution (intent to cellular immunotherapy cohort: 20 patients, stand-alone treatment cohort: nine patients). The overall response rate was 69.0% (complete response 27.6%). The median progression-free survival was 5.1 months, with a 9.5-month median overall survival. In the intent to cellular immunotherapy cohort, 11 of 19 patients received chimeric antigen receptor T-cell (CAR-T) infusions, and one patient received allogeneic stem cell transplantation. Four patients received Pola-BR therapy, including bendamustine before leukapheresis, and all produced CAR-T products successfully. 3 of the 28 patients experienced grade3 or higher adverse events, and two required treatment discontinuation. Our single institution, a real-world cohort of R/R DLBCL patients showed high efficacy outcomes and a tolerable toxicity profile for Pola-BR therapy, which is comparable to previous studies. More cases are needed to determine its impact on CAR-T therapy and stem cell transplantation.

Clinical significance of late CMV disease in adult patients who underwent allogeneic stem cell transplant.

INTRODUCTION: Late cytomegalovirus (CMV) disease, which was defined as CMV disease occurring >100 days post-transplant, remains an important complication among allogeneic stem cell transplant recipients, even now that the prophylactic strategy using ganciclovir preemptive therapy has been established. Due to the recent expansion of donor sources and conditioning regimens, it is therefore appropriate to reevaluate the incidence, risk factors, and clinical impacts of late CMV disease. METHODS: This study included the 1295 adult patients, who underwent transplant for the first time from 2008 to 2015, without underlying disease relapse or CMV disease within 100 days post-transplant. There were no restrictions on underlying diseases or transplant procedures. RESULTS: During the median follow-up period of 48.4 months, 21 patients developed late CMV disease and the 5-year cumulative incidence of late CMV disease was 1.6%. By multivariate analysis, haploidentical related donor, adult T-cell leukemia lymphoma, and preemptive therapy before 100 days post-transplant were extracted as independent risk factors. Late CMV disease negatively affected transplant outcomes, and was identified as an independent risk factor for the non-relapse mortality rate (hazard ratio 3.83, p < 0.001) and overall survival rate (hazard ratio 4.01, p < 0.001). Although 17 of 21 patients with late CMV disease died, the main causes of death were not related to CMV, except in three patients with CMV pneumonia. CONCLUSIONS: Although the incidence of late CMV disease is low in transplant recipients, this complication negatively affects clinical courses. Therefore, transplant recipients with these risk factors should be more carefully managed.

Impact of gene alterations on clinical outcome in young adults with myelodysplastic syndromes.

Young adults with myelodysplastic syndrome (MDS) are rare, and the clinical significance of driver mutations has not yet been analysed. We analysed the gene mutations and copy number alterations (CNAs) in younger MDS patients using next-generation sequencing, targeting 68 genes that were recurrently mutated in myeloid malignancies, to investigate the correlation between their genetic alterations and clinical outcomes. We enrolled 55 patients retrospectively (aged < 50 years). At least one mutation was detected in 56% of the patients. The most frequently mutated genes were ASXL1 and RUNX1, 13% each. We defined higher-risk patients as those with ≥ 2 mutations, except for SF3B1 mutation, and/or CNA. The 3-year overall survival (OS) in patients with a higher-risk was lower than that in those with a lower-risk (50.8% vs. 71.8%, P = 0.024). Among the 44 transplant recipients, patients with higher-risk had a significantly lower OS and tended to have a higher cumulative incidence of relapse (CIR) than those with a lower-risk (3-year OS: 38.0% vs. 64.4%, P = 0.039; 3-year CIR: 44.0% vs. 24.1%, P = 0.076). Our results showed that genetic aberrations can predict clinical outcomes in younger MDS patients, despite the low rate of genetic mutations.

Clinical impact and early prediction of carbapenem-resistant Pseudomonas aeruginosa bacteraemia in allogeneic hematopoietic stem cell transplantation recipients.

OBJECTIVE: Although antipseudomonal agents are administered in high-risk patients, no reports have focused on the risk of carbapenem-resistant (CR) Pseudomonas aeruginosa bacteraemia in allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients. METHODS: We retrospectively studied a cohort of adult allo-HSCT recipients with P. aeruginosa bacteraemia, focusing on a comparison between carbapenem-sensitive (CS) and CR P. aeruginosa after initiating conditioning chemotherapy at our institute between January 2005 and December 2020. The incidence, all-cause 30-d mortality of P. aeruginosa bacteraemia, and risk factors for carbapenem resistance among patients with P. aeruginosa bacteraemia in allo-HSCT recipients were evaluated. RESULTS: Forty-eight patients with P. aeruginosa bacteraemia were included, with an incidence of 3.84/100 recipients (CS = 1.92 vs. CR = 1.92). The all-cause 30-d mortality was significantly higher in CR P. aeruginosa bacteraemia (CS = 4.2% vs. CR = 39.1%; P = 0.003). The factor significantly associated with CR P. aeruginosa bacteraemia was carbapenem use for at least 3 d within 30 d before the onset of bacteraemia (odds ratio = 8.92; 95% confidence interval: 1.35-58.90). Inappropriate antimicrobial selection was significantly more frequent in CR P. aeruginosa bacteraemia (CS = 0% vs. CR = 29.2%; P ˂ 0.009). CONCLUSION: Empirical combination therapy with reference to antimicrobial susceptibility profiles in each institution should be considered when CR P. aeruginosa bacteraemia is suspected in allo-HSCT recipients based on the risk of carbapenem exposure.

Phase I trial of myeloablative conditioning with 3-day total marrow and lymphoid irradiation for leukemia.

This prospective phase I trial aimed to determine the recommended dose of 3-day total marrow and lymphoid irradiation (TMLI) for a myeloablative conditioning regimen by increasing the dose per fraction. The primary end-point of this single-institution dose escalation study was the recommended TMLI dose based on the frequency of dose-limiting toxicity (DLT) ≤100 days posthematopoietic stem cell transplantation (HSCT); a 3 + 3 design was used to evaluate the safety of TMLI. Three dose levels of TMLI (14/16/18 Gy in six fractions over 3 days) were set. The treatment protocol began at 14 Gy. Dose-limiting toxicities were defined as grade 3 or 4 nonhematological toxicities. Nine patients, with a median age of 42 years (range, 35-48), eight with acute lymphoblastic leukemia and one with chronic myeloblastic leukemia, received TMLI followed by unrelated bone marrow transplant. The median follow-up period after HSCT was 575 days (range, 253-1037). Three patients were enrolled for each dose level. No patient showed DLT within 100 days of HSCT. The recommended dose of 3-day TMLI was 18 Gy in six fractions. All patients achieved neutrophil engraftment at a median of 19 days (range, 14-25). One-year overall and disease-free survival rates were 83.3% and 57.1%, respectively. Three patients experienced relapse, and no nonrelapse mortality was documented during the observation period. One patient died due to disease relapse 306 days post-HSCT. The recommended dose of 3-day TMLI was 18 Gy in six fractions. The efficacy evaluation of this regimen is currently being planned in a phase II study.

Attenuated humoral response against SARS-CoV-2 mRNA vaccination in allogeneic stem cell transplantation recipients.

Antibody persistence several months after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccination in allogeneic stem cell transplantation recipients remains largely unknown. We sequentially evaluated the humoral response to two doses of mRNA vaccines in 128 adult recipients and identified the risk factors involved in a poor response. The median interval between stem cell transplantation and vaccination was 2.7 years. The SARS-CoV-2 S1 Ab became positive after the second vaccination dose in 87.6% of the recipients, and the median titer was 1235.4 arbitrary units (AU)/ml. In patients on corticosteroid treatment, the corticosteroid dose inversely correlated with Ab titer. Multivariate analysis identified risk factors for poor peak response such as an interval from stem cell transplantation ≤1 year, history of clinically significant CMV infection, and use of >5 mg/day prednisolone at vaccination. Six months after vaccination, the median titer decreased to 185.15 AU/ml, and use of >5 mg/day prednisolone at vaccination was significantly associated with a poor response. These results indicate that early vaccination after stem cell transplantation (<12 months) and CMV infection are risk factors for poor peak response, while steroid use is important for a peak as well as a persistent response. In conclusion, although humoral response is observed in many stem cell transplantation recipients after two doses of vaccination, Ab titers diminish with time, and factors associated with persistence and a peak immunity should be considered separately.

[Tisagenlecleucel for relapsed/refractory diffuse large B-cell lymphoma: real-world data from single institute experience].

Chimeric antigen receptor (CAR) T-cell therapy has revolutionized the approach to patients with relapsed or refractory diffuse large B-cell lymphoma (r/r DLBCL). This study retrospectively analyzed patients treated with commercially available tisagenlecleucel at our hospital and evaluated its safety and effectiveness. Of the 21 patients evaluated, any grade and grade ≥3 cytokine release syndrome (CRS) occurred in 85.7% and 9.5% of the patients, respectively. A total of 66.7% received tocilizumab and 28.6% received glucocorticoids for the treatment of CRS. The complete response (CR) rate at 3 months was 61.9% (95% confidence interval [CI] 38.4-81.9). After a median follow-up of 6.3 months following CAR-T infusion, the progression-free survival (PFS) and overall survival rates at 6 months were 53.1% (95%CI 28.3-72.7) and 69.2% (95%CI 43.7-84.9), respectively. Severe cytopenia and hypogammaglobulinemia occurred frequently following CAR-T infusion. Eight patients (38.1%) had comorbidities that would have made them ineligible for leukapheresis in the JULIET trial. However, the presence of comorbidities at the time of leukapheresis had no significant effect on the rates of CR, PFS, and adverse events. Tisagenlecleucel for r/r DLBCL in the real-world setting showed high efficacy and manageable safety profile comparable with the pivotal trial.

Outcomes of allogeneic haematopoietic stem cell transplantation with intensity-modulated total body irradiation by helical tomotherapy: a 2-year prospective follow-up study.

BACKGROUND AND OBJECTIVES: Intensity-modulated radiation therapy (IMRT) helps achieve good radiation dose conformity and precise dose evaluation. We conducted a single-centre prospective study to assess the safety and feasibility of total body irradiation with IMRT (IMRT-TBI) using helical tomotherapy in allogeneic haematopoietic stem cell transplantation (allo-HSCT). PATIENTS AND METHODS: Thirty-nine adult patients with haematological malignancy (acute lymphoblastic leukaemia [n = 21], chronic myeloid leukaemia [n = 6], mixed phenotype acute leukaemia [n = 5], acute myeloid leukaemia [n = 4], and malignant lymphoma [n = 3]) who received 12 Gy IMRT-TBI were enrolled with a median follow-up of 934.5 (range, 617-1254) d. At the time of transplantation, 33 patients (85%) achieved complete remission. The conditioning regimen used IMRT-TBI (12 Gy in 6 fractions twice daily, for 3 d) and cyclophosphamide (60 mg/kg/d, for 2 d), seven patients were combined with cytarabine, and five with etoposide. We set dose constraints for the lungs, kidneys and lens as the organs at risk. RESULTS: The mean doses for the lungs and kidneys were 7.50 and 9.11 Gy, respectively. The mean maximum dose for the lens (right/left) was 5.75/5.87 Gy. The 2-year overall survival (OS), disease-free survival (DFS), cumulative incidence of relapse (CIR) and non-relapse mortality (NRM) were 69, 64, 18 and 18%, respectively. Thirty-six patients developed early adverse events (AEs) (including four patients with Grade 3/4 toxicities), most of which were reversible oral mucositis and may partially have been related to IMRT-TBI. However, the incidence of toxicity was comparable to conventional TBI-based conditioning transplantation. None of the patients developed primary graft failure, or Grade III-IV acute graft-versus-host disease (GVHD). In late complications, chronic kidney disease was observed in six patients, a lower incidence compared to conventional TBI-based conditioning transplantation. No radiation pneumonitis or cataracts were observed in any of the patients. CONCLUSIONS: IMRT-TBI is safe and feasible for haematological malignancies with acceptable clinical outcomes.KEY MESSAGESIMRT-TBI-helical tomotherapy aids in accurate dose calculation and conformity.It could be used without any considerable increase in the rate of TBI-related AEs.Allo-HSCT with IMRT-TBI may be an alternative to conventional TBI for clinical use.

[Haploidentical hematopoietic stem cell transplantation for graft failure in myelodysplastic syndrome/myeloproliferative neoplasm-unclassifiable complicated with Stenotrophomonas maltophilia bacteremia].

A 60-year-old woman with myelodysplastic syndrome/myeloproliferative neoplasm-unclassifiable underwent unrelated bone marrow transplantation from a human leukocyte antigen (HLA) 8/8 allele-matched male donor. Neutrophil engraftment was achieved on day 29. Fluorescence in situ hybridization of sex chromosomes demonstrated complete donor chimerism. The red blood cell and platelet transfusion dependence continued, and the neutrophil count decreased gradually. Despite prolonged administration of broad-spectrum antibiotics for febrile neutropenia, blood cultures on days 46 and 58 returned positive for Stenotrophomonas maltophilia (SM). Contrast-enhanced computed tomography revealed multiple nodules of septic emboli in the lungs and kidneys, suggesting a disseminated SM infection. Antibiotic therapy was conducted based on antimicrobial susceptibility testing. However, the blood cell count failed to normalize and a secondary graft failure was diagnosed. A HLA-haploidentical peripheral-blood stem-cell transplantation from the patient's son was performed on day 134 after the initial transplantation. Neutrophil engraftment was achieved on day 11. Red blood cells and platelets were also engrafted. After the resolution of the SM bacteremia, the patient was discharged on day 63. The prognosis of the SM bacteremia with neutropenia is poor. Antibiotic treatment based on antimicrobial susceptibility testing and a second transplant from an HLA-haploidentical donor likely contributed to the successful outcome in this patient.

[Clinical features of thyroid dysfunction in adult Japanese after allogeneic hematopoietic stem cell transplantation].

We examined the incidence and clinical features of thyroid dysfunction in 661 patients who received allogeneic hematopoietic stem cell transplantation (allo-HSCT) in our hospital. At a median of 2.5 (1.0-11.3) years, 28 patients (4.2%) developed subclinical hypothyroidism, and 16 patients (2.4%) developed hypothyroidism. Eight of 16 patients (50%) with hypothyroidism were positive for anti-thyroid antibodies. Ten of 44 patients (22.7%) with thyroid dysfunction were discovered more than 5 years after allo-HSCT. Thyroid dysfunction with late onset was common in allo-HSCT recipients, and thyroid function should be monitored on a regular basis.

Weight-adjusted urinary creatinine excretion predicts transplant outcomes in adult patients with acute myeloid leukemia in complete remission.

Sarcopenia is a prognostic factor for cancer. Because creatinine is formed from creatine phosphate in muscle tissue, urinary creatinine excretion (UCE) serves as an index of muscle volume. However, as of yet, there are no studies assessing the clinical impact of UCE or weight- adjusted urinary creatinine excretion (WA-UCE) on allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients. We analyzed the association between pre-transplant WA-UCE and transplant outcomes among 164 adult patients with acute myeloid leukemia in complete remission who underwent their first allo-HSCT at our center. The patients were classified into a high (n = 106) and a low WA-UCE group (n = 58) for predicting overall survival (OS) based on the receiver operating characteristics curve. On multivariate analysis, low WA-UCE was associated with poor OS, progression-free survival and a high incidence of non-relapse mortality. WA-UCE has the potential to be an objective biomarker for predicting transplant outcomes, especially the incidence of infection-related death.

Dose-finding trial of azacitidine as post-transplant maintenance for high-risk MDS: a KSGCT prospective study.

This 3+3 dose-escalation phase I multicenter study investigated the optimal dose of azacitidine (AZA) for post-hematopoietic stem cell transplantation (HSCT) maintenance, which remains unknown in Japan. Recipients of a first HSCT for high-risk myelodysplastic syndromes (MDS, n = 12) or acute myeloid leukemia (AML) with antecedent MDS (n = 3) received post-HSCT AZA maintenance in 2015-2019. The optimal AZA dose was defined as the dose at which 50-70% of patients can complete four cycles without dose-limiting toxicity (DLT). The initial dose level 1 was set as 30 mg/m2 for 5 days per 28-day cycle, and dose levels 0, 2, and 3 were set as 20, 40, and 50 mg/m2. DLT was defined as any grade 3 non-hematological or grade 4 hematological toxicity. The 15 evaluable patients were 55 (37-64) years old. The median observation of the post-HSCT survivors was 935 (493-1915) days. The median number of days post-HSCT to the start of AZA was 101 (59-176). In the first, second, and third cohorts, five of nine patients completed four cycles at dose level 1. In the final cohort, five of six additional patients completed at the same dose. In total, 10 (67%) patients tolerated AZA 30 mg/m2, which was determined as optimal. DLT occurred in five cases: grade 3 hepatotoxicity, pneumonia, enterocolitis, and grade 4 thrombocytopenia and neutropenia. The 2-year overall survival and disease-free survival rates post-HSCT were 77.0% and 73.3%. Post-HSCT AZA maintenance was well-tolerated and merits further evaluation for patients with MDS or AML with antecedent MDS. Trial registration: UMIN000018791.

Impact of lung function impairment after allogeneic hematopoietic stem cell transplantation.

Late-onset noninfectious pulmonary complications (LONIPC) are a major cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (HSCT). However, the clinical impact of lung function deterioration itself in long-term adult survivors of HSCT remains to be fully investigated. This retrospective, longitudinal study aimed to investigate pulmonary function following HSCT in terms of its change and the clinical significance of its decline. We examined 167 patients who survived for at least 2 years without relapse. The median follow-up period was 10.3 years. A linear mixed-effects model showed that the slope of pulmonary function tests values, including percent vital capacity (%VC), percent forced expiratory volume in one second (%FEV1), and FEV1/forced VC ratio (FEV1%), decreased over time. The cumulative incidence of newly obstructive and restrictive lung function impairment (LFI) at 10 years was 15.7% and 19.5%, respectively. Restrictive LFI was a significant, independent risk factor for overall survival (hazard ratio 7.11, P = 0.007) and non-relapse mortality (hazard ratio 12.19, P = 0.003). Our data demonstrated that lung function declined over time after HSCT and that the decline itself had a significant impact on survival regardless of LONIPC.

Central nervous system mucormycosis in a patient with hematological malignancy: A case report and review of the literature.

Invasive mucormycosis is a refractory fungal infection. Central nervous system (CNS) mucormycosis is a rare complication caused by infiltration from the paranasal sinuses or hematogenous dissemination. Here, we present a case of a brain abscess, due to mucormycosis, diagnosed using burr craniotomy. A 25-year-old Japanese woman with relapsed-refractory acute lymphoblastic leukemia underwent cord blood transplantation (CBT). The patient experienced prolonged and profound neutropenia, and oral voriconazole was administered as primary antifungal prophylaxis. The patient received a conditioning regimen on day -11 and complained of aphasia and right hemiparesis on day -6. Magnetic resonance imaging (MRI) revealed a T2-weighted high-intensity area in the left frontal cortex. A brain abscess was suspected, and liposomal amphotericin B (L-AMB) administration was started. The patient underwent CBT as scheduled and underwent neutrophil engraftment on day 14. Although the patient achieved complete remission on day 28, her consciousness level gradually deteriorated. MRI revealed an enlarged brain lesion with a midline shift sign, suggesting brain herniation. Craniotomy was performed to relieve intracranial pressure and drain the abscess on day 38, and a diagnosis of cerebral mucormycosis was confirmed. The L-AMB dose was increased to 10 mg/kg on day 43. Although the patient's consciousness level improved, she died of hemorrhagic cystitis and aspiration pneumonia. Cerebral mucormycosis should be suspected if neurological symptoms are observed in stem cell transplant recipients. Prompt commencement of antifungal therapy and debridement are crucial because mucormycosis has a poor prognosis.

[Klinefelter's syndrome diagnosed at the onset of acute myeloid leukemia with inv (16) following treatment for germ cell tumor].

A 22-year-old man with a history of mediastinal germ cell tumor, which was diagnosed at age 20 and remained disease-free after chemotherapy, was diagnosed with acute myeloid leukemia (AML) M2 in January 2020. Karyotype analysis of bone marrow (BM) specimen at diagnosis detected 47,XXY, inv (16) in all cells. Following induction treatment, he achieved complete remission with a remarkable decrease in the minimal residual disease marker. Although considered related to therapy, the AML had a prognostically favorable karyotype, and the initial treatment response was very good. He had no human leukocyte antigen-matched sibling donor candidate. Thus, allogeneic hematopoietic stem cell transplantation was not scheduled at the first complete remission. After three cycles of consolidation therapy, he remained disease-free for over one year. Karyotype analysis of BM during remission revealed that all analyzed cells harbored 47,XXY, and Klinefelter syndrome (KS) was diagnosed. Although the patient experienced an adjustment disorder on KS diagnosis, he had overcome the difficulty with the assistance of psycho-oncologists, clinical psychologists, and genetic counselors. Herein, we report this rare case of KS that manifested after AML diagnosis following mediastinal germ cell tumor treatment.

Immunological influence of serum-free manufactured umbilical cord-derived mesenchymal stromal cells for steroid-resistant acute graft-versus-host disease.

This study investigated the safety, efficacy, and immunological influence of allogeneic umbilical cord-derived mesenchymal stromal cells (IMSUT-CORD) processed in serum-free medium and cryoprotectant, for treating steroid-resistant acute graft-versus-host disease (aGVHD). In a phase I dose-escalation trial, IMSUT-CORD were infused intravenously twice weekly over two cycles with up to two additional cycles. Four patients received a dose of 1 × 106 cells/kg, while three received 2 × 106/kg. Of 76 total adverse events, fourteen associated or possibly associated adverse events included 2 cases of a hot flash, headache, and peripheral neuropathy, 1 each of upper abdominal pain, hypoxia, increased γ-GTP, somnolence, peripheral vascular pain at the injection site, thrombocytopenia, hypertension, and decreased fibrinogen. At 16 weeks after the initial IMSUT-CORD infusion, three patients showed complete response (CR), two partial response (PR), one mixed response, and one no response. The overall response rate was 71.4%, and the continuous CR/PR rate was 100% for over 28 days after CR/PR. NK cell count significantly increased and correlated with treatment response, whereas IL-12, IL-17, and IL-33 levels decreased, but did not correlate with treatment response. CCL2 and CCL11 levels increased during IMSUT-CORD therapy. IMSUT-CORD are usable in patients with steroid-resistant aGVHD (UMIN000032819: https://www.umin.ac.jp/ctr ).

[Late-onset refractory autoimmune hemolytic anemia following autologous hematologic recovery after allo-HSCT in aplastic anemia-PNH syndrome].

A 31-year-old man underwent allogeneic bone marrow transplantation (BMT) for the treatment of transfusion-dependent aplastic anemia (AA) after conditioning with a regimen including fludarabine, cyclophosphamide, and antithymocyte globulin. The patient developed a late graft rejection on day 103 and showed autologous hematologic recovery not requiring transfusions on day 76. Peripheral blood leukocytes were of 100% recipient origin on day 103, and paroxysmal nocturnal hematuria (PNH)-type granulocytes were detected 5 months after BMT. The patient suddenly experienced hemolytic symptoms triggered by cold stimulation, and was diagnosed with autoimmune hemolytic anemia (AIHA) 37 months after BMT. Although anemia was ameliorated by prednisolone (PSL), hemolytic attacks repeatedly occurred, which became refractory to corticosteroids. Moreover, the patient underwent a splenectomy for the steroid-resistant AIHA and achieved AIHA remission without the need for PSL at 53 months after BMT. The immune tolerance breakdown to erythrocyte antigens was thought to have occurred due to various factors including immune AA, medication, cold stimulation, and infection, leading to AIHA development in this case.

Prognostic Factors for Outcomes of Allogeneic HSCT for Children and Adolescents/Young Adults With CML in the TKI Era.

The breakthrough effects of tyrosine kinase inhibitors (TKIs) have lessened indications for allogeneic hematopoietic stem cell transplantation (HSCT) in chronic myeloid leukemia (CML). However, HSCT is still attractive for children and adolescents/young adults (AYAs) requiring lifelong TKI therapy. Nevertheless, little has been reported on the outcomes of large clinical studies of HSCT targeting these age groups. This study aimed to identify prognostic factors for the outcomes of HSCT, including reduced-intensity conditioning (RIC)-HSCT, for children and AYAs with CML in the TKI era. We performed a registry analysis for 200 patients with CML aged <30 years who underwent pretransplant TKI therapy from the observational nationwide database established by the Japanese Society for Transplantation and Cellular Therapy. The patients received bone marrow (BM), peripheral blood (PB), or cord blood (CB) from either related or unrelated donors. The indication for HSCT for individual patients was determined by the institution according to European LeukemiaNet recommendations and other guidelines. The 5-year overall survival (OS) rates for patients with chronic phase (CP) (n = 124), accelerated phase (AP) (n = 23), and blastic phase (BP) (n = 53) at diagnosis were 82.8%, 71.1%, and 73.3%, respectively, with no significant difference (P =.3293). The strongest predictor of engraftment was transplant source, with CB (hazard ratio [HR], 0.33) and PB (HR, 2.00) (compared with BM) being independent unfavorable and favorable predictors, respectively. Transplant source was also an independent predictor of chronic GVHD, with PB (HR, 1.81) and CB (HR, 0.39) (compared with BM) being unfavorable and favorable predictors, respectively. The strongest predictor of OS rate for patients with CP at diagnosis was disease phase at HSCT, with second or greater CP, AP, or BP (HR, 2.81) (compared with first CP [CP1]) being an unfavorable predictor. In addition, patients with CP at diagnosis who had major and complete molecular responses at HSCT had excellent outcomes, with 5-year OS rates of 100% and 94.4%, respectively. The 5-year OS rate was compared between RIC (n = 31) and myeloablative conditioning (MAC) (n = 58) in patients with CP1, both of which were 89.3%, with no significant difference (P = .9440). On univariate analysis for the RIC cohort with CP at diagnosis, the age at HSCT (HR, 1.27) (increase per year) and the time from diagnosis to HSCT (HR, 1.83) (increase per year) were significant predictors for OS. Our study demonstrates that RIC may be an appropriate alternative to MAC for children and AYAs with CP1. As for the transplant source, we recommend first selecting BM because of a higher engraftment rate compared to CB and a lower incidence of chronic GVHD compared to PB. Although HSCT in the status of a major molecular response is desirable, it is not advisable to continue TKI pointlessly long because age at HSCT and timing of HSCT are prognostic factors that determine survival. The decision to perform RIC-HSCT instead of continuing TKI should be carefully made, considering the possibility of transplant-related complications.