Key Points Bacterial diversity was restored after FMT with oral frozen capsules, with improvement of diarrhea. Oral FMT for steroid-refractory acute gGVHD is feasible and could be effective.

Cytomegalovirus (CMV) infection is a major complication in allogeneic stem cell transplantation. The utility of CMV prophylaxis with letermovir has been reported; however, the specific applications remain unclear. In this study, we retrospectively analyzed large-scale registry data (N = 10 480) to clarify the risk factors for nonrelapse mortality (NRM) in connection with CMV reactivation. First, we identified risk factors for CMV reactivation using multivariate analysis and developed a scoring model. Although the model effectively stratified reactivation risk into 3 groups (43.7% vs 60.9% vs 71.5%; P < .001), the 3-year NRM was significantly higher in patients with CMV reactivation, even in the low (20.9% vs 13.0%, P < .001), intermediate (21.4% vs 15.6%; P < .001), and high (29.3% vs 18.0%; P < .001) reactivation risk groups. Next, survival analysis considering competing risks, time-dependent covariates, and interaction terms for exploring the heterogeneous impact of CMV reactivation on NRM in the training cohort revealed that chronic myeloid leukemia (CML) (hazard ratio [HR], 1.76; 95% confidence interval [CI], 1.05-2.96; P = .033), good performance status (PS) (HR, 1.42; 95% CI, 1.04-1.94; P = .028), HLA-matched donor (HR, 1.34; 95% CI, 1.06-1.70; P = .013), and standard-risk disease (HR, 1.28; 95% CI, 1.04-1.58; P = .022) were associated with increased NRM. In the test cohort, CMV reactivation was significantly associated with increased 3-year NRM among patients with 2 to 4 factors (22.1% vs 13.1%; P < .001) but was comparable among patients with 0 or 1 factor (23.2% vs 20.4%; P = .62). We propose that CMV prophylaxis should be determined based on reactivation risk, as well as these other factors.

Polycomb repressive complexes (PRCs) are epigenetic regulators that mediate repressive histone modifications. PRCs play a pivotal role in the maintenance of hematopoietic stem cells through repression of target genes involved in cell proliferation and differentiation. Next-generation sequencing technologies have revealed that various hematologic malignancies harbor mutations in PRC2 genes, such as EZH2, EED, and SUZ12, and PRC1.1 genes, such as BCOR and BCORL1. Except for the activating EZH2 mutations detected in lymphoma, most of these mutations compromise PRC function and are frequently associated with resistance to chemotherapeutic agents and poor prognosis. Recent studies have shown that mutations in PRC genes are druggable targets. Several PRC2 inhibitors, including EZH2-specific inhibitors and EZH1 and EZH2 dual inhibitors have shown therapeutic efficacy for tumors with and without activating EZH2 mutations. Moreover, EZH2 loss-of-function mutations appear to be attractive therapeutic targets for implementing the concept of synthetic lethality. Further understanding of the epigenetic dysregulation associated with PRCs in hematological malignancies should improve treatment outcomes.

No standard therapy for peripheral T-cell lymphomas (PTCLs) has been established, and treatment outcomes are poor. Upfront stem cell transplantation has been investigated in several studies, some of which have reported promising outcomes. However, some patients maintain long-term remission after chemotherapy alone. It is thus important to predict sensitivity to first-line chemotherapy to optimize treatment strategies. In the present study, we retrospectively analyzed time to treatment failure (TTF) of first-line chemotherapy in 59 patients with PTCLs. On multivariate analysis for TTF, elevated lactate dehydrogenase level, hypoalbuminemia, and high neutrophil-to-lymphocyte ratio were significant prognostic factors. Using these three factors, we also developed a new model that effectively distinguished patient outcomes. The TTF rate at 1 year from diagnosis was 71.4% in patients with score 0 (0 factor), 31.8% with score 1 (1 factor) and 4.5% with score 2 (2-3 factors) (P< 0.001). The prognostic power was superior to that of the Prognostic Index for PTCL-unspecified score. Patients with scores of 1 and 2 had poor TTF, and may be candidates for upfront stem cell transplantation if they respond to first-line chemotherapy. Further investigation in a larger cohort is warranted to determine the general applicability of this score.

Total body irradiation using intensity-modulated radiation therapy total body irradiation (IMRT-TBI) by helical tomotherapy in allogeneic hematopoietic stem cell transplantation (allo-HSCT) allows for precise evaluation and adjustment of radiation dosage. We conducted a single-center pilot study to evaluate the safety of IMRT-TBI for allo-HSCT recipients. Patients with hematological malignancies in remission who were scheduled for allo-HSCT with TBI-based myeloablative conditioning were eligible. The primary endpoint was the incidence of adverse events (AEs). Secondary endpoints were engraftment rate, overall survival, relapse rate, non-relapse mortality, and the incidence of acute and chronic graft-versus-host disease (aGVHD and cGVHD, respectively). Between July 2018 and November 2018, ten patients were recruited with a median observation duration of 571 days after allo-HSCT (range, 496–614). D80% for planning target volume (PTV) in all patients was 12.01 Gy. Average D80% values for lungs, kidneys and lenses (right/left) were 7.50, 9.03 and 4.41/4.03 Gy, respectively. Any early AEs (within 100 days of allo-HSCT) were reported in all patients. Eight patients experienced oral mucositis and gastrointestinal symptoms. One patient experienced Bearman criteria grade 3 regimen-related toxicity (kidney and liver). All cases achieved neutrophil engraftment. There was no grade III–IV aGVHD or late AE. One patient died of sinusoidal obstruction syndrome 67 days after allo-HSCT. The remaining nine patients were alive and disease-free at final follow-up. Thus, IMRT-TBI was well tolerated in terms of early AEs in adult patients who underwent allo-HSCT; this warrants further study with longer observation times to monitor late AEs and efficacy.