An open-label study of belumosudil, a selective ROCK2 inhibitor, as second or subsequent line of therapy for steroid-dependent/steroid-resistant chronic GVHD.

Belumosudil mesylate is a selective Rho-associated coiled-coil kinase 2 inhibitor with immunomodulatory and antifibrosis effects. This multicenter, open-label, single-arm study evaluated belumosudil 200 mg once daily as second or subsequent line of therapy (LOT) in 21 Japanese patients ≥12 years of age with steroid-dependent/steroid-resistant chronic graft-versus-host disease (cGVHD). The primary endpoint of best overall response rate (ORR) at 24 weeks after enrollment of the last patient was 85.7% (95% confidence interval [CI]: 63.7-97.0), and the lower limit of the 95% CI exceeded the pre-defined threshold of 25%. The Kaplan-Meier estimate of duration of response rate at 24 weeks was 75% (95% CI: 46-90); 13/18 responders (72.2%) had a sustained response for ≥20 weeks. The median time to response was 4.1 weeks (range 3.90-8.10); ORR was 47.6% at 4 weeks and 75.0% at 24 weeks; best ORR was 80% for joints/fascia, 66.7% for the mouth, and 54.5% for skin. Overall, 57.1% of patients had clinically meaningful symptom improvement at least once; the median duration of symptom improvement was 22.2 weeks (range 4.0-51.3). Corticosteroid dose reductions were recorded for 57.1% of patients. Median failure-free and overall survival were not reached. Treatment-emergent adverse events occurred in 85.7% of patients (most commonly diarrhea, 19.0%), of which 38.1% were drug-related. There were no drug-related discontinuations or deaths. In summary, belumosudil 200 mg once daily as second or subsequent LOT in Japanese patients with steroid-dependent/steroid-resistant cGVHD was effective, with no new safety concerns.

Overcoming minimal residual disease using intensified conditioning with medium-dose etoposide, cyclophosphamide and total body irradiation in allogeneic stem cell transplantation for Philadelphia chromosome-positive acute lymphoblastic leukemia in adults.

BACKGROUND AIMS: An intensified conditioning regimen incorporating medium-dose etoposide (VP16) is an option for patients with acute lymphoblastic leukemia (ALL). However, the prognostic impacts of the addition of VP16 to cyclophosphamide (CY) and total body irradiation (TBI) in patients with Philadelphia chromosome-positive (Ph+) ALL with regard to minimal residual disease (MRD) status have not been elucidated. METHODS: The authors retrospectively compared the outcomes of patients with Ph+ ALL who underwent allogeneic transplantation following VP16/CY/TBI (n = 101) and CY/TBI (n = 563). RESULTS: At 4 years, the VP16/CY/TBI group exhibited significantly better disease-free survival (DFS) (72.6% versus 61.7%, P = 0.027) and relapse rate (11.5% versus 21.1%, P = 0.020) and similar non-relapse mortality (16.0% versus 17.2%, P = 0.70). In subgroup analyses, the beneficial effects of the addition of VP16 on DFS were more evident in patients with positive MRD status (71.2% versus 48.4% at 4 years, P = 0.022) than those with negative MRD status (72.8% versus 66.7% at 4 years, P = 0.24). Although MRD positivity was significantly associated with worse DFS in patients who received CY/TBI (48.4% versus 66.7%, P < 0.001), this was not the case in those who received VP16/CY/TBI (71.2% versus 72.8%, P = 0.86). CONCLUSIONS: This study demonstrated the benefits of the addition of VP16 in Ph+ ALL patients, especially those with positive MRD status. VP16/CY/TBI could be a potential strategy to overcome the survival risk of MRD positivity.

Risk factors for lower respiratory tract disease and outcomes in allogeneic hematopoietic stem cell transplantation recipients with influenza virus infection.

INTRODUCTION: Influenza virus infection (IVI) is frequent in allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients, and reports from several countries indicate high morbidity and mortality from progression to lower respiratory tract disease (LRTD). However, there have been no reports on IVI clinical characteristics, treatment outcomes, and risk factor for progression to LRTD among allo-HSCT recipients in Japan. METHODS: We retrospectively reviewed the medical charts of allo-HSCT recipients who developed IVI between 2012 and 2019. RESULTS: Forty-eight cases of IVI following allo-HSCT were identified at our institution. The median age was 42 years, and median time from allo-HSCT to IVI was 25 months. Thirty-seven patients (77.1%) were administered neuraminidase inhibitors (NAIs) as antiviral therapy within 48 h of symptom onset (early therapy), whereas 11 (22.9%) received NAI over 48 h after onset (delayed therapy). Subsequently, 12 patients (25.0%) developed LRTD after IVI. Multivariate analysis identified older age (hazard ratio [HR], 7.65; 95% confidence interval [CI], 2.22-26.3) and bronchiolitis obliterans (HR, 5.74; 95% CI, 1.57-21.0) as independent risk factors for progression to LRTD. Moreover, land-mark analysis showed that early therapy prevented progression to LRTD (11.8% vs. 45.5%, P = 0.013). The IVI-related mortality rate was 2.1%. CONCLUSIONS: Early NAI treatment is recommended for reducing the risk of LRTD progression due to IVI in allo-HSTC recipients, particularly for older patients and those with bronchiolitis obliterans.

Association between measurable residual disease kinetics and outcomes of Philadelphia chromosome-positive acute lymphoblastic leukemia.

The prognosis of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph + ALL) has improved dramatically. Although measurable residual disease (MRD) kinetics during pretransplant treatment has been recently reported to correlate with patient outcomes, it is unclear whether prognosis is better if the MRD falls below the detection sensitivity soon after induction therapy. We retrospectively analyzed data of 37 Ph + ALL patients who were treated with autologous or allogeneic stem cell transplantation (auto-SCT, allo-SCT) at our institute from 2003 to 2019. Based on MRD kinetics, patients were divided into three groups: early responders (MRD became negative after induction therapy [n = 10, 27.0%]); late responders (MRD remained positive after induction therapy and became negative just before SCT [n = 12, 32.4%]); and poor responders (MRD was positive until just before SCT [n = 15, 40.5%]). The 5-year disease-free survival (DFS) rates for the three groups were 80.0%, 60.0%, and 29.9%, respectively (P = 0.037). The 5-year overall survival rates were not significantly different. The 5-year relapse rates were 0.0%, 31.7%, and 49.5%, respectively (P = 0.045). Non-relapse mortality (NRM) rates were similar among the three groups. Subgroup analysis for the cases that received posttransplantation tyrosine kinase inhibitor maintenance therapy revealed that DFS was similarly dependent on MRD kinetics (P = 0.022). This study clarified that MRD kinetics was a significant prognosticator for DFS and relapse rate in Ph + ALL.

A Prospective, Longitudinal Observation of the Incidence, Treatment, and Survival of Late Acute and Chronic Graft-versus-Host Disease by National Institutes of Health Criteria in a Japanese Cohort.

To prospectively validate the incidence, manifestations, and outcomes of graft-versus-host disease (GVHD) by National Institutes of Health criteria, we recruited 406 hematopoietic stem cell transplantation recipients at 16 transplant centers in Japan from May 2012 to June 2014. The 2-year cumulative incidence of late acute and chronic GVHD was 3.2% (n = 13) and 35.4% (n = 145), with a median onset of 3.6 and 4.7 months after transplant, respectively. The global severity at onset was mild in 30.3%, moderate in 43.5%, and severe in 26.2%. Eighty-two patients were followed up for 2 years, with 79.3% still manifesting GVHD symptoms, and 80.6% (n = 117) of the patients received systemic immunosuppressive treatment (IST), with a 2-year cumulative incidence of IST termination of 33.1%. Severe patients showed a significantly lower rate of IST termination than those with mild and moderate severities (mild, 38.5%; moderate, 40.9%; and severe, 17.2%). The 2-year incidence of nonrelapse mortality (NRM) and relapse was not significantly different according to the severity at onset (NRM: mild [16.6%] versus moderate [8.7%] versus severe [16.1%]; relapse: mild [14.9%] versus moderate [14.7%] versus severe [5.3%]). As a result, 2-year overall survival (OS) and GVHD-specific survival (GSS) were equivalent according to the severity at onset (mild: OS = 81.0%, GSS = 85.7%; moderate: OS = 84.2%, GSS = 92.5%; severe: OS = 83.9%, GSS = 89.2%). Our study helped identify the characteristics of late acute and chronic GVHD in Japanese patients. Further investigation is needed to identify an optimal endpoint for survival prediction.

Machine Learning Prediction Model for Neutrophil Recovery after Unrelated Cord Blood Transplantation.

Delayed neutrophil recovery is an important limitation to the administration of cord blood transplantation (CBT) and leaves the recipient vulnerable to life-threatening infection and increases the risk of other complications. A predictive model for neutrophil recovery after single-unit CBT was developed by using a machine learning method, which can handle large and complex datasets, allowing for the analysis of massive amounts of information to uncover patterns and make accurate predictions. Japanese registry data, the largest real-world dataset of CBT, was selected as the data source. Ninety-eight variables with observed values for >80% of the subjects known at the time of CBT were selected. Model building was performed with a competing risk regression model with lasso penalty. Prediction accuracy of the models was evaluated by calculating the area under the receiver operating characteristic curve (AUC) using a test dataset. The primary outcome was neutrophil recovery at day (D) 28, with recovery at D14 and D42 analyzed as secondary outcomes. The final cord blood engraftment prediction (CBEP) models included 2991 single-unit CBT recipients with acute leukemia. The median AUC of a D28-CBEP lasso regression model run 100 times was .74, and those for D14 and D42 were .88 and .68, respectively. The predictivity of the D28-CBEP model was higher than that of 4 different legacy models constructed separately. A highly predictive model for neutrophil recovery by 28 days after CBT was constructed using machine learning techniques; however, identification of significant risk factors was insufficient for outcome prediction for an individual patient, which is necessary for improving therapeutic outcomes. Notably, the prediction accuracy for post-transplantation D14, D28, and D42 decreased, and the model became more complex with more associated factors with increased time after transplantation.

Fetal hemoglobin level predicts lower-risk myelodysplastic syndrome.

The relationship between fetal hemoglobin (HbF) levels and disease prognosis in patients with myelodysplastic syndrome (MDS) is unclear. This study aimed to clarify the relationship between HbF level and the prognosis of MDS. To this end, data from 217 patients diagnosed with MDS between April 2006 and August 2020 at Ebina General Hospital were analyzed retrospectively. The primary endpoint was leukemia-free survival (LFS) for 5 years after diagnosis. HbF levels were significantly higher in patients with MDS than in control patients without MDS (n = 155), with a cut-off value of 0.4%. Higher-risk patients had a similar prognosis regardless of HbF level, but lower-risk patients had longer LFS at intermediate HbF levels. Although prognosis based on pre-treatment HbF levels did not differ significantly among azacitidine-treated patients, prognosis tended to be better in lower-risk patients with intermediate HbF levels. Multivariate analysis showed that the intermediate HbF category correlated with LFS, independently of MDS lower-risk prognostic scoring system (LR-PSS)-related factors. This study is the first to assess the association between HbF levels and the new World Health Organization 2016 criteria for MDS, demonstrating the significance of HbF levels in the prognosis of MDS.

Long-term Use of Ibrutinib in Japanese Patients with Steroid Dependent/Refractory cGVHD: Final Analysis of Multicenter Study.

Background: Chronic graft-versus-host disease (cGVHD) is a serious complication after allogeneic stem cell transplantation. Poor prognosis has been shown in patients with cGVHD after the failure of primary steroid-based treatments. A previous report demonstrated the efficacy and safety of ibrutinib in these patients, leading to the approval of ibrutinib for cGVHD in Japan. Here, we report the extended follow-up of patients in this study. Objectives: To evaluate the safety and efficacy of ibrutinib in Japanese patients with steroid-dependent or refractory cGVHD. Study Design: An open-label, single-arm, multicenter study of ibrutinib in Japanese patients with steroid-dependent or refractory cGVHD (NCT No.: NCT03474679; Clinical Registry No.: CR108443). Results: At the time of the final data cutoff, 7/19 (36.8%) patients completed the study treatment, and 12/19 (63.2%) patients discontinued ibrutinib. After a median follow-up of 31.11 months (range:1.9 to 38.6 months), the best overall response rate was 84.2% (16/19 patients; 95% CI:60.4%, 96.6%) in all treated populations, with a median time to response of 2.81 (range:1.0 to 27.6) months. Of 15 responders with ≥2 organs involved at baseline, seven (46.7%) had responses in multiple organs. An improvement in the organ response rate was observed for the skin, eye, mouth, and esophagus compared with that in a previous report. The rate of sustained response for ≥20 weeks, ≥32 weeks, and ≥44 weeks were 68.8%, 62.5%, and 50.0%, respectively for 16 responders. The median daily corticosteroid dose requirement tended to decrease over time for all treated analysis sets. Twelve of 19 patients (63.2%) reached a corticosteroid dose of <0.15 mg/kg/day for at least one week, and four (21.1%) discontinued corticosteroid treatment for at least 28 days during the study. The failure-free and overall survival rates at 30 months were 62.7% and 62.0%, respectively. The safety findings of this updated analysis were consistent with the safety profile observed at the time of the primary analysis and the known ibrutinib safety profile. Common grade ≥3 treatment-emergent adverse events (TEAEs) were pneumonia (6/19 [31.6%] patients), platelet count decreased, and cellulitis (3/19 [15.8%] patients each). After the primary analysis, no new TEAEs leading to death, treatment discontinuation, or dose reduction were reported, and no new patients reported major hemorrhage. Cardiac arrhythmia (Grade 2 atrial flutter) was reported in 1/19 (5.3%) patients. No new safety signs were observed despite prolonged ibrutinib exposure. Conclusions: The final results support previous conclusions, demonstrating a clinically meaningful response and acceptable safety profile of ibrutinib in Japanese patients with steroid-dependent or refractory cGVHD.

Donor cord blood aging accelerates in recipients after transplantation.

Cord blood stem cell transplantation is an important alternative for patients needing hematopoietic stem cell transplantation. However, it is unclear how cord blood cells, which are 0 years old, age in the recipient's body after allogeneic transplantation. We performed DNA methylation (DNAm) age analysis to measure the age of cells using post-transplant peripheral blood in 50 cases of cord blood transplantation. The median chronological age (the time elapsed from the date of the cord blood transplant to the day the sample was taken for DNAm analysis) of donor cells was 4.0 years (0.2-15.0 years), while the median DNAm age was 10.0 years (1.3-30.3 years), and the ratio of DNAm age to chronological age (AgeAccel) was 2.7 (1.2-8.2). When comparing the mean values of AgeAccel in cord blood transplant cases and controls, the values were significantly higher in cord blood transplant cases. The characteristics of patients and transplant procedures were not associated with AgeAccel in this analysis, nor were they associated with the development of graft-versus-host disease. However, this analysis revealed that transplanting 0-year-old cord blood into a recipient resulted in cells aging more than twice as quickly as the elapsed time. The results shed light on the importance of the mismatch between cord blood stem cells and donor environmental factors in stem cell aging.

Association of CDKN2A/2B deletion with relapse after hematopoietic stem cell transplantation for acute lymphoblastic leukemia.

The most important prognostic factor for Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) is minimal residual disease (MRD). Previous studies have reported copy number variants of genes such as IKZF1, CDKN2A/2B, and PAX5. These gene mutations can be analyzed using multiplex ligation-dependent probe amplification (MLPA), which is less costly and easier to perform than large-scale gene mutation analyses. In this study, we performed copy number variant analysis of leukemia cells at the first onset of Ph+ALL in a case series of allogeneic hematopoietic stem cell transplantation (allo-HSCT) using the MLPA method. We analyzed how it influenced allo-HSCT prognosis together with MRD information. CDKN2A/2B copy number variations significantly increased the rate of post-transplant recurrence (P=0.025) and significantly reduced disease-free survival (P=0.015). Additionally, patients with IKZF1 deletions had a significantly higher post-transplant recurrence rate (P=0.042). Although they were positive for pre-transplant MRD, no relapse was observed in patients with wild-type copy number variations in IKZF1 or CDKN2A/2B. CDKN2A/2B copy number variation is a crucial factor that can be confirmed at initial onset as a post-transplant prognostic factor of Ph+ALL.

Outcomes of salvage haploidentical transplantation using posttransplant cyclophosphamide for graft failure following allogeneic hematopoietic stem cell transplantation.

Haploidentical donors have emerged as an alternative donor source for salvage stem cell transplantation (SCT) after graft failure; however, data regarding salvage haploidentical SCT using posttransplant cyclophosphamide (PTCy) are limited. Using nationwide data (2011-2019), we retrospectively investigated transplant outcomes after salvage haploidentical SCT using PTCy for graft failure (n = 33, median age 34 years). The total dose of PTCy was 75-100 mg/kg (standard dose) in 26 patients (78.8%) and 40-50 mg/kg (lower dose) in 5 patients (15.2%). The neutrophil engraftment rate at 30 days was 81.8%. One-year overall survival (OS) and non-relapse mortality (NRM) rates were 47.4% and 46.0%, respectively. The standard-dose group exhibited better OS (61.1% vs. 0.0% at 1 year, P = 0.022) and NRM (35.1% vs. 80.0% at 1 year, P = 0.052) than the lower-dose group. Moreover, the standard-dose group was less prone to both grades II-IV (11.5% vs. 40.0%) and III-IV (0.0% vs. 40.0%) acute graft-versus-host disease (GVHD). Use of cyclophosphamide in previous SCT and conditioning did not affect OS or NRM. In conclusion, haploidentical salvage SCT using PTCy offers promising survival outcomes. Prospective studies are required to validate the efficacy of salvage haploidentical SCT using PTCy.

An Open-Label, Single-Arm, Multicenter Study of Ibrutinib in Japanese Patients With Steroid-dependent/Refractory Chronic Graft-Versus-Host Disease.

Chronic graft-versus-host disease (cGVHD) is a serious complication after allogeneic stem cell transplantation. There are no well-established treatment options for cGVHD after primary steroid-based treatment. Ibrutinib showed clinical benefit with an acceptable safety profile in steroid-dependent/refractory cGVHD patients in a Phase 1b/2 study (PCYC-1129-CA, NCT02195869), with which it was approved in the United States for adult cGVHD patients after failure of ≥1 systemic treatments. This open-label, single-arm, multicenter study was conducted to evaluate the efficacy, safety, pharmacokinetics, and pharmacodynamics of ibrutinib in Japanese patients ≥12 years of age with steroid-dependent/refractory cGVHD (NCT03474679). Patients were assessed on the basis of the National Institutes of Health (NIH) Consensus Development Project Criteria for Clinical Trials in cGVHD (2014). All patients received ibrutinib at a dose of 420 mg orally once daily, with a dose reduction to 280 mg/d on the concomitant use of voriconazole. Nineteen patients, including 1 adolescent, were enrolled and treated with ibrutinib in the study. At the time of clinical data cutoff (when the last patient completed the efficacy assessment at week 37), 10 of 19 patients (52.6%) remained on treatment whereas 9 of 19 patients (47.4%) had discontinued ibrutinib. The median duration of ibrutinib treatment was 9.63 (range 0.6 to 16.7+) months. The best overall response rate was 73.7%, and the rate of sustained response for ≥20 weeks was 71.4% for the responders (52.6% of all patients). Responses were seen across all the involved organs for cGVHD. Median daily corticosteroid dose requirement decreased by 0.06 mg/kg/d from baseline to week 36, whereas an improvement in the Lee cGVHD Symptom Scale score was observed in 42.1% of patients. The most common treatment-emergent adverse events (TEAEs) were pneumonia and stomatitis (36.8% each), upper respiratory tract infection (31.6%), cellulitis and platelet count decreased (26.3% each), and nausea (21.1%). Furthermore, 11 of 19 patients (57.9%) were reported with ≥1 treatment-emergent serious adverse events; the most common being pneumonia (26.3%) and cellulitis (15.8%). In total, 4 of 19 patients (21.1%) died during the study, of which 3 of 19 patients (15.8%) had TEAEs leading to death whereas 1 patient died of peritonitis, which occurred >30 days after the last dose of ibrutinib. Treatment-emergent adverse events leading to ibrutinib discontinuation were reported in 3 of 19 patients (15.8%). Ibrutinib was rapidly absorbed with a median time to reach maximum plasma concentration (tmax) of ~4.0 hours. Steady-state exposures were ~3.0- and ~1.4-fold higher for the patients receiving fluconazole (n = 8) and voriconazole (n = 4) with ibrutinib, respectively, as compared with patients not receiving CYP3A inhibitors (n = 7). Mean Bruton's tyrosine kinase occupancy was 88.1% at 4 hours after dose on day 1, and occupancy levels were maintained throughout the assessment period, regardless of the ibrutinib daily dose. Ibrutinib showed a clinically meaningful response and an acceptable safety profile in Japanese patients with steroid-dependent/refractory cGVHD; the safety profile was consistent with the known safety profile of ibrutinib in adults and with that seen in cGVHD patients receiving concomitant steroid treatment. Overall, the results were generally consistent with findings observed in the PCYC-1129-CA study.

A case of JAK2V617F-positive essential thrombocythemia where allele burden was reduced by a PD-1 inhibitor.

The Janus kinase/signal transducers and activators of transcription signaling pathway induces programmed death ligand-1 (PD-L1) expression. JAK2 mutation at position 617 (JAK2V617) is a frequent driver of myeloproliferative neoplasms (MPN) through PD-L1 expression. Although PD-1 inhibitors should be effective against MPN with JAK2V617F mutation, this has not yet been reported in humans. Thus, we assessed the efficacy of a PD-1 inhibitor in a lung cancer patient with JAK2V617F-positive essential thrombocythemia (ET). A 71-year-old man was diagnosed with ET, and with lung carcinoma 3 years later. After right lobectomy and postoperative chemotherapy, pembrolizumab [a PD-1 inhibitor (200 mg, every 3 weeks)] was initiated for refractory lung carcinoma. Lung cancer progression did not occur for 1.5 years under treatment. Most megakaryocytes were PD-L1-positive, and after pembrolizumab initiation, platelet count remained below 45 × 104/µL without the need for other cytoreductive therapies for ET. The JAK2V617F allele burden gradually decreased from 11.5% at diagnosis to 2.9% after 17 months of pembrolizumab treatment. Other peripheral blood lineages did not decrease, and pembrolizumab treatment was continued without any adverse events. This is the first report demonstrating the effectiveness of pembrolizumab in an MPN patient with JAK2V617F mutation.

The Role of Hypertension and Renin-angiotensin-aldosterone System Inhibitors in Bleomycin-induced Lung Injury.

INTRODUCTION: The risk factors for bleomycin-induced lung injury (BLI), a fatal complication of cancer chemotherapy, are not well-established. The renin-angiotensin-aldosterone system (RAAS) has recently been suggested to play a role in the development of lung injury. This study clarified the impact of hypertension (HTN) and the administration of RAAS inhibitors on BLI occurrence in patients treated with bleomycin-containing regimens. PATIENTS AND METHODS: We retrospectively analyzed the data of 190 patients treated with a bleomycin-containing regimen for Hodgkin lymphoma or germ cell tumors at our institutions from 2004 to 2018. RESULTS: Overall, 190 patients received bleomycin, and symptomatic BLI occurred in 21 (11.1%) cases. In the multivariate analysis, age ≥ 65 years (odd ratio, 10.90; 95% confidence interval, 3.72-32.20; P < .001) and history of HTN (odds ratio, 3.32; 95% confidence interval, 1.07-10.30; P = .04) were found to be significant risk factors for BLI onset. BLI occurred in 3.6% (n = 5) of patients with no risk, 11.8% (n = 2) of those whose only risk factor was HTN, 31.6% (n = 6) of those whose only risk factor was age ≥ 65 years, and 57.1% (n = 8) of those with both risk factors (P < .001). BLI-induced mortality rates in each group were 0.0% (n = 0), 5.9% (n = 1), 10.5% (n = 2), and 42.9% (n = 6) (P < .001), respectively. Among 31 patients with HTN, BLI incidence was 12.5% in patients who were administered RAAS inhibitors and 53.3% in those who were not (P = .02). CONCLUSION: Older age and history of HTN were independent risk factors for the development of BLI, and the administration of RAAS inhibitors might reduce the onset of BLI.

An analysis of oral microbial flora by T-RFLP in patients undergoing hematopoietic stem cell transplantation.

Even though the hematopoietic stem cell transplantation (HSCT) procedure has been improved, oral mucositis (OM) is still a severe complication of the conditioning regimen. We investigated the association between OM severity and the alteration of oral bacterial flora using 16S rRNA gene-based terminal restriction fragment length polymorphism (T-RFLP) analysis in 19 consecutive patients undergoing HSCT. Oral samples were collected at pre-transplantation, at the peak of mucositis and post-engraftment. T-RFLP profiles for each timepoint were constructed into an X-Y matrix, and the distances between timepoints were calculated. Patients with severe and moderate OM had larger changes in their oral bacterial flora from before HSCT to peak of mucositis than controls (p = 0.031 and 0.016, respectively). Moreover, severe mucositis was significantly associated with an extended period of fever until engraftment, high maximum C-reactive protein levels, and prolonged periods of opioid treatment and intravenous hyper-alimentation. These findings suggest that mucositis severity is associated with the magnitude of change in the oral bacterial flora. This novel finding may help advance strategies for the prevention or treatment of OM after HSCT.

Clinicopathological evaluation of methotrexate-associated lymphoproliferative disorders with special focus on Epstein-Barr virus-positive mucocutaneous lesions.

Some patients diagnosed with methotrexate-associated lymphoproliferative disorder (MTX-LPD) develop spontaneous regression upon the discontinuation of MTX, whereas others require chemotherapy. The mechanisms underlying this differential response and the capacity to spontaneously regress are not clearly understood. We evaluated numerous clinicopathological features in 63 patients diagnosed with MTX-LPD, with a special focus on those with Epstein-Barr virus (EBV)-positive mucocutaneous lesions (EBVMCL). The diagnosis of EBVMCL included cases of both EBV-positive mucocutaneous ulcers (EBVMCU) and diffuse gingival swelling associated with proliferation of EBV-positive large B-cells. Of the four subgroups of MTX-LPD, one-year treatment-free survival (TFS) after the discontinuation of MTX was achieved among those with EBVMCL (100%), diffuse large B-cell lymphoma (57%), Hodgkin-like lesions (60%), or classical Hodgkin lymphoma (29%); a significant difference in TFS was observed when comparing the responses of patients with EBVMCL to the those diagnosed with other subtypes. Multivariate analysis revealed predictive factors for prolonged TFS that included EBV-positive lesions and comparatively low levels of serum LDH. Taken together, our study suggests that a diagnosis of EBVMCL is related to the overall clinical outcome after the discontinuation of MTX.

Primary CNS post-transplant lymphoproliferative disorder following haploidentical HSCT using post-transplant high-dose cyclophosphamide.

Neurological complications after hematopoietic stem cell transplantation (HSCT) are frequently life-threatening, and their clinical management can be highly challenging. In the case of central nervous system lesions post-HSCT, a definitive diagnosis is often difficult to reach because many different causative and contributing conditions may be present, including bacterial, fungal, or viral infections; original disease relapse; and post-transplant lymphoproliferative disorder (PTLD). Here, we report a case of a 32-year-old male patient with Philadelphia chromosomepositive acute lymphoid leukemia who underwent three HSCTs and was then diagnosed with primary central nervous system (PCNS) PTLD by brain biopsy. The third HSCT was a haplo-identical peripheral blood stem cell transplantation from his mother, with post-transplant high-dose cyclophosphamide and tacrolimus used as graft-versus-host disease prophylaxis. Four months after the HSCT, multiple small ring lesions were detected in the parabasal ganglia of the patient's brain during magnetic resonance imaging. A lesion biopsy indicated Epstein-Barr virus (EBV)-positive, diffuse large B-cell lymphoma. Because the patient had no evidence of systemic lymphadenopathy, we diagnosed him with PCNS-PTLD. There was no EBV DNA in this patient's cerebrospinal fluid. The diagnosis of PCNS-PTLD by EBV DNA polymerase chain reaction is difficult and highlights the importance of a brain biopsy to diagnose PCNS-PTLD, especially in cases showing no EBV DNA in the cerebrospinal fluid. Although a rare condition, it is essential to locate and analyze cases of PCNS-PTLD after HSCT to establish the optimal strategy for treatment or prophylaxis.

Successful treatment with low-dose nivolumab in refractory Hodgkin lymphoma after allogeneic stem cell transplantation.

Previous studies have reported that an antibody that blocks programmed cell death 1 (PD-1) has therapeutic activity in patients with refractory/relapsed Hodgkin lymphoma (HL). However, the safety and efficacy of these agents in the post-allogeneic stem cell transplantation (allo-SCT) setting are not well known. Here, we describe a patient who was diagnosed as classical HL and treated with five regimens of chemotherapies with autologous SCT. Complete remission (CR) was not achieved following this initial treatment, so we performed allo-SCT from an HLA-matched sibling donor. Since his disease progressed at day 403 after allo-SCT, we decided to use nivolumab in the treatment of his refractory disease. To prevent the worsening of his chronic graft-versus-host disease (GVHD), we reduced the initial dose and frequency of nivolumab compared with the previous report. After four courses of 0.5 mg/kg of nivolumab every three weeks, FDG-PET imaging showed partial response (PR) to the treatment, a remarkable result. However, since the escalated dose of 2 mg/kg resulted in worsening of dyspnea and skin sclerosis, we initiated systemic administration of prednisolone and reduced nivolumab to 1 mg/kg. At the time of this report, his HL is in stable PR with three weekly administration of nivolumab and steroid controlled mild chronic GVHD.

Bacterial Pneumonia-induced Persistent Remission of Severe Immune Thrombocytopenia after Allogeneic Hematopoietic Stem Cell Transplantation.

A 53-year-old woman with chronic myeloid leukemia received allogeneic hematopoietic stem cell transplantation. After neutrophil engraftment, her platelet count exceeded 100,000/µL at day 64. While she was receiving corticosteroid treatment for chronic graft versus host disease (GVHD), her platelets suddenly dropped to 6,000/µL at day 210 and she was diagnosed with immune thrombocytopenia (ITP). Corticosteroids, intravenous high-dose gamma globulin (IVIg) and a splenectomy failed to increase her platelet count. She developed bacterial pneumonia at day 599 and antibiotic therapy was initiated. Soon after, her platelet count continuously increased. Her GVHD and ITP are now in remission without any ongoing treatment.