Efficient estimation for left-truncated competing risks regression for case-cohort studies.

The case-cohort study design provides a cost-effective study design for a large cohort study with competing risk outcomes. The proportional subdistribution hazards model is widely used to estimate direct covariate effects on the cumulative incidence function for competing risk data. In biomedical studies, left truncation often occurs and brings extra challenges to the analysis. Existing inverse probability weighting methods for case-cohort studies with competing risk data not only have not addressed left truncation, but also are inefficient in regression parameter estimation for fully observed covariates. We propose an augmented inverse probability-weighted estimating equation for left-truncated competing risk data to address these limitations of the current literature. We further propose a more efficient estimator when extra information from the other causes is available. The proposed estimators are consistent and asymptotically normally distributed. Simulation studies show that the proposed estimator is unbiased and leads to estimation efficiency gain in the regression parameter estimation. We analyze the Atherosclerosis Risk in Communities study data using the proposed methods.

Asthma as a Risk Factor for Hospitalization in Children and Youth With COVID-19: A Retrospective Cohort Study.

BACKGROUND: Studies examining the association between asthma and hospitalization among children and youth with coronavirus disease 2019 (COVID-19) have yielded mixed results. Both asthma and COVID-19 hospitalization are characterized by racial, ethnic and socioeconomic disparities which also pattern geographically, yet no studies to date have adjusted for neighborhood context in the assessment of this association. METHODS: Mixed effects logistic regression was used to estimate the association between asthma and hospitalization due to COVID-19 in a sample of 28,997 children and youth diagnosed with COVID-19 in Milwaukee County, Wisconsin, from March 1, 2020, to May 31, 2022. Models adjusted for individual-level sociodemographic factors (age, gender, race, ethnicity and city/suburb residence) and season of diagnosis were examined as moderators. Random intercepts by census tract accounted for geographic variation in neighborhood factors and census tract-level measures of education, health and environment, and social and economic factors were assessed via childhood opportunity indices. RESULTS: Asthma history was statistically significantly associated with hospitalization due to COVID-19 among children and youth. Hospitalization rates varied statistically significantly by census tract, and results were unchanged after accounting for childhood opportunity indices and census tract. Season of diagnosis was not found to moderate the effect of asthma history on COVID-19 hospitalization. CONCLUSION: Our study suggests that asthma history is a risk factor for hospitalization in the context of COVID-19 infection among children and youth, warranting observation and follow-up of children with asthma as well as continued measures to prevent COVID-19 in this population.

The analysis of multiple outcomes, multiple variables and variables selection in hematopoietic cell transplantation studies.

It is common to study time-to-event data in cancer research such as hematopoietic cell transplantation (HCT) for leukemia. The extensive work has been done for the univariate survival outcome, that is, one event type. However, in practice a subject is often exposed to multiple types of outcomes. In this article, we review various types of right-censored data with multiple outcome types including competing risks data, recurrent event data, and composite endpoints. We also provide hematopoietic cell transplantation data examples.

Sample size and power determination for multiparameter evaluation in nonlinear regression models with potential stratification.

Sample size and power determination are crucial design considerations for biomedical studies intending to formally test the effects of key variables on an outcome. Other known prognostic factors may exist, necessitating the use of techniques for covariate adjustment when conducting this evaluation. Moreover, the main interest often includes assessing the impact of more than one variable on an outcome, such as multiple treatments or risk factors. Regression models are frequently employed for these purposes, formalizing this assessment as a test of multiple regression parameters. But, the presence of multiple variables of primary interest and correlation between covariates can complicate sample size/power calculation. Given the paucity of available sample size formulas for this context, these calculations are often performed via simulation, which can be both time-consuming as well as demanding extensive probability modeling. We propose a simpler, general approach to sample size and power determination that may be applied when testing multiple parameters in commonly used regression models, including generalized linear models as well as ordinary and stratified versions of the Cox and Fine-Gray models. Through both rigorous simulations and theoretical derivations, we demonstrate the formulas' accuracy in producing sample sizes that will meet the type I error rate and power specifications of the study design.

A simple prognostic system in patients with myelofibrosis undergoing allogeneic stem cell transplantation: a CIBMTR/EBMT analysis.

To develop a prognostic model for patients undergoing allogeneic hematopoietic cell transplantation (allo-HCT) for myelofibrosis (MF), we examined the data of 623 patients undergoing allo-HCT between 2000 and 2016 in the United States (the Center for International Blood and Marrow Transplant Research [CIBMTR] cohort). A Cox multivariable model was used to identify factors prognostic of mortality. A weighted score using these factors was assigned to patients who received transplantation in Europe (the European Bone Marrow Transplant [EBMT] cohort; n = 623). Patient age >50 years (hazard ratio [HR], 1.39; 95% confidence interval [CI], 0.98-1.96), and HLA-matched unrelated donor (HR, 1.29; 95% CI, 0.98-1.7) were associated with an increased hazard of death and were assigned 1 point. Hemoglobin levels <100 g/L at time of transplantation (HR, 1.63; 95% CI, 1.2-2.19) and a mismatched unrelated donor (HR, 1.78; 95% CI, 1.25-2.52) were assigned 2 points. The 3-year overall survival (OS) in patients with a low (1-2 points), intermediate (3-4 points), and high score (5 points) were 69% (95% CI, 61-76), 51% (95% CI, 46-56.4), and 34% (95% CI, 21-49), respectively (P < .001). Increasing score was predictive of increased transplant-related mortality (TRM; P = .0017) but not of relapse (P = .12). The derived score was predictive of OS (P < .001) and TRM (P = .002) but not of relapse (P = .17) in the EBMT cohort as well. The proposed system was prognostic of survival in 2 large cohorts, CIBMTR and EBMT, and can easily be applied by clinicians consulting patients with MF about the transplantation outcomes.

Clinical impact of cryopreservation of allogeneic hematopoietic cell grafts during the onset of the COVID-19 pandemic.

At the onset of the COVID-19 pandemic, the National Marrow Donor Program mandated the cryopreservation of hematopoietic cell grafts from volunteer unrelated donors because of numerous patient and donor safety concerns and logistical hurdles. Using the Center for International Blood and Marrow Transplant Research outcomes database, we report the impact of cryopreservation on overall survival (OS) and other outcomes within 1 year after hematopoietic cell transplantation (HCT). We analyzed 1543 recipients of cryopreserved allografts receiving HCT at US centers during the first 6 months of the pandemic and compared them with 2499 recipients of fresh allografts during a 6-month period in 2019. On multivariable regression analysis, we observed no difference in the OS (P = .09), nonrelapse mortality (P = .89), graft-versus-host disease (GVHD), or GVHD- and relapse-free survival (P = .58) in recipients of cryopreserved vs fresh allografts. Disease-free survival (DFS) was lower in the cryopreserved allograft recipients (P = .006) because of a higher risk of relapse (P = .01) compared with the fresh allograft recipients. Primary graft failure was higher (P = .01), and the risk of chronic GVHD was lower (P = .001) with cryopreservation compared with fresh grafts. In conclusion, although there was no negative impact of cryopreservation on OS, relapse was higher, and DFS was lower than that with no cryopreservation. Fresh grafts are recommended as the pandemic-related logistical hurdles resolve. Cryopreservation should be considered an option for patients when fresh grafts are not feasible.

Effect of Autograft CD34+ Dose on Outcome in Pediatric Patients Undergoing Autologous Hematopoietic Stem Cell Transplant for Central Nervous System Tumors.

Consolidation with autologous hematopoietic stem cell transplantation (HSCT) has improved survival for patients with central nervous system tumors (CNSTs). The impact of the autologous graft CD34+ dose on patient outcomes is unknown. We wanted to analyze the relationship between CD34+ dose, total nucleated cell (TNC) dose, and clinical outcomes, including overall survival (OS), progression-free survival (PFS), relapse, non-relapse mortality (NRM), endothelial-injury complications (EIC), and time to neutrophil engraftment in children undergoing autologous HSCT for CNSTs. A retrospective analysis of the CIBMTR database was performed. Children aged <10 years who underwent autologous HSCT between 2008 to 2018 for an indication of CNST were included. An optimal cut point was identified for patient age, CD34+ cell dose, and TNC, using the maximum likelihood method and PFS as an endpoint. Univariable analysis for PFS, OS, and relapse was described using the Kaplan-Meier estimator. Cox models were fitted for PFS and OS outcomes. Cause-specific hazards models were fitted for relapse and NRM. One hundred fifteen patients met the inclusion criteria. A statistically significant association was identified between autograft CD34+ content and clinical outcomes. Children receiving >3.6×106/kg CD34+ cells experienced superior PFS (p = .04) and OS (p = .04) compared to children receiving ≤3.6 × 106/kg. Relapse rates were lower in patients receiving >3.6 × 106/kg CD34+ cells (p = .05). Higher CD34+ doses were not associated with increased NRM (p = .59). Stratification of CD34+ dose by quartile did not reveal any statistically significant differences between quartiles for 3-year PFS (p = .66), OS (p = .29), risk of relapse (p = .57), or EIC (p = .87). There were no significant differences in patient outcomes based on TNC, and those receiving a TNC >4.4 × 108/kg did not experience superior PFS (p = .26), superior OS (p = .14), reduced risk of relapse (p = .37), or reduced NRM (p = .25). Children with medulloblastoma had superior PFS (p < .001), OS (p = .01), and relapse rates (p = .001) compared to those with other CNS tumor types. Median time to neutrophil engraftment was 10 days versus 12 days in the highest and lowest infused CD34+ quartiles, respectively. For children undergoing autologous HSCT for CNSTs, increasing CD34+ cell dose was associated with significantly improved OS and PFS, and lower relapse rates, without increased NRM or EICs.

Marginal semiparametric transformation models for clustered multivariate competing risks data.

Multivariate survival models are often used in studying multiple outcomes for right-censored data. However, the outcomes of interest often have competing risks, where standard multivariate survival models may lead to invalid inferences. For example, patients who had stem cell transplantation may experience multiple types of infections after transplant while reconstituting their immune system, where death without experiencing infections is a competing risk for infections. Such competing risks data often suffer from cluster effects due to a matched pair design or correlation within study centers. The cumulative incidence function (CIF) is widely used to summarize competing risks outcomes. Thus, it is often of interest to study direct covariate effects on the CIF. Most literature on clustered competing risks data analyses is limited to the univariate proportional subdistribution hazards model with inverse probability censoring weighting which requires correctly specifying the censoring distribution. We propose a marginal semiparametric transformation model for multivariate competing risks outcomes. The proposed model does not require modeling the censoring distribution, accommodates nonproportional subdistribution hazards structure, and provides a platform for joint inference of all causes and outcomes.

The Impact of Pre-Apheresis Health Related Quality of Life on Peripheral Blood Progenitor Cell Yield and Donor's Health and Outcome: Secondary Analysis of Patient-Reported Outcome Data from the RDSafe and BMT CTN 0201 Clinical Trials.

There is a lack of evidence about how health-related quality of life (HRQoL), including psychosocial factors, might affect donation-related experiences and clinical markers in the context of hematopoietic stem cell donation. The broader literature suggests that psychological factors, including anxiety and depression, are associated with higher levels of inflammatory burden leading to poorer postprocedural outcomes including longer hospital stays and increased pain perception. In this study, we aimed to evaluate whether predonation HRQoL markers predict toxicity profile and stem cell yield after peripheral blood stem cell (PBSC) donation in healthy donors. The study population comprised adult granulocyte colony-stimulating factor mobilized PBSC-related donors (RD) (n = 157) and unrelated donors (URD) (n = 179) enrolled in the related donor safety study (RDSafe) and Blood and Marrow Transplant Clinical Trials Network (BMT CTN) 0201 clinical trials. Pre-donation HRQoL was assessed using the Short-Form-12 (SF-12) in RDSafe and SF-8 questionnaire in BMT CTN 0201 (higher score is better). The aims of this study were to (a) determine the impact of pre-donation HRQoL on peri-collection pain and acute toxicities experienced and (b) to investigate the pre-procedural HRQoL indicators on stem cells yield. URDs were younger than RDs (median age 35 versus 63). A higher proportion of RDs were female (50% versus 40%) and obese (41% versus 35%). A higher proportion of RD PBSC donations required 2 days or more of apheresis (44% versus 21%). More RD collections were lower volume procedures (<18L, 16% versus 28%), and required a central line (28% versus 11%). RDs were more likely to report pre-donation grade 1-2 pain (27% versus 8%) and other toxicities (16% versus 6%). Among RDs, a lower pre-donation physical component summary (PCS) score was associated with significantly more grade 2-4 pain at 1 month (P = .004) and at 1-year after donation (P = .0099) in univariable analyses. In multivariable analysis, pre-donation PCS remained significantly associated with grade 2-4 pain 1 month after donation (P = .0098). More specifically, RDs with predonation PCS scores in the highest quartile were less likely to report pain compared with donors with PCS scores in the lowest quartile (odds ratio 0.1; 95% confidence interval 0.01-0.83; P = .005). There was also a trend toward higher grade 2-4 pain at 1-year post-donation among RDs with lower predonation PCS score (P = .018). Among URDs, neither PCS nor mental component summary (MCS) scores were associated with pain or toxicities at any time point after donation based on the univariable analysis. Because of low rates of postdonation grade 2-4 pain and toxicities, multivariable analysis was not performed in the URD setting. Moreover, there was no correlation between preapheresis HRQoL score (PCS or MCS) and PBSC collection yield in either the RD or URD setting. Our study demonstrates that pre-donation HRQoL scores are significantly associated with the toxicity profile after PBSC donation in the RD setting, with adult RDs with lower predonation physical HRQoL experiencing higher levels of pain at 1 month and persisting up to 12 months after a PBSC collection procedure. There were no such associations found in URD. Our findings can help clinicians identify donors at higher risk of pain with donation, and lead to personalized information and interventions for specific donors. Lack of correlation between predonation HRQoL and stem cell yield may be due to a small sample size and warrants further evaluation.

Noninfectious Pulmonary Toxicity after Allogeneic Hematopoietic Cell Transplantation.

Noninfectious pulmonary toxicity (NPT), a significant complication of allogeneic hematopoietic cell transplantation (alloHCT), includes idiopathic pneumonia syndrome (IPS), diffuse alveolar hemorrhage (DAH), and cryptogenic organizing pneumonia (COP), with an overall incidence ranging from 1% to 15% in different case series and a variable mortality rate. A registry study of the epidemiology and outcomes of NPT after alloHCT has not been conducted to date. The primary objective of the present study was to assess the incidence of and risk factors for IPS, DAH, and COP; the secondary objective was to assess overall survival (OS) in patients developing NPT. This retrospective study included adult patients who underwent alloHCT between 2008 and 2017 and reported to the Center for International Blood and Marrow Transplant Research. Multivariable Cox proportional hazards regression models were developed to identify the risk factors for development of NPT and for OS, by including pretransplantation clinical variables and time-dependent variables of neutrophil and platelet recovery, and acute graft-versus-host disease (GVHD) post-transplantation. This study included 21,574 adult patients, with a median age of 55 years. According to the HCT Comorbidity Index (HCT-CI), 24% of the patients had moderate pulmonary comorbidity and 15% had severe pulmonary comorbidity. The cumulative incidence of NPT at 1 year was 8.1% (95% confidence interval [CI], 7.7% to 8.5%). Individually, the 1-year cumulative incidences of IPS, DAH, and COP were 4.9% (95% CI, 4.7% to 5.2%), 2.1% (95% CI, 1.9% to 2.3%), and .7% (95% CI, .6% to .8%), respectively. Multivariable analysis showed that severe pulmonary comorbidity, grade II-IV acute GVHD, mismatched unrelated donor and cord blood transplantation, and HCT-CI score ≥1 significantly increased the risk of NPT. In contrast, alloHCT performed in 2014 or later, non-total body irradiation (TBI)- and TBI-based nonmyeloablative conditioning and platelet recovery were associated with a decreased risk. In a landmark analysis at day+100 post-transplantation, the risk of DAH was significantly lower in patients who had platelet recovery by day +100. Multivariable analysis for OS demonstrated that NPT significantly increased the mortality risk (hazard ratio, 4.2; P < .0001).

Does recipient body mass index inform donor selection for allogeneic haematopoietic cell transplantation?

It is not known whether obesity has a differential effect on allogeneic haematopoietic cell transplantation outcomes with alternative donor types. We report the results of a retrospective registry study examining the effect of obesity [body mass index (BMI) > 30] on outcomes with alternative donors (haploidentical related donor with two or more mismatches and receiving post-transplant cyclophosphamide [haplo] and cord blood (CBU)] versus matched unrelated donor (MUD). Adult patients receiving haematopoietic cell transplantation for haematologic malignancy (2013-2017) (N = 16 182) using MUD (n = 11 801), haplo (n = 2894) and CBU (n = 1487) were included. The primary outcome was non-relapse mortality (NRM). The analysis demonstrated a significant, non-linear interaction between pretransplant BMI and the three donor groups for NRM: NRM risk was significantly higher with CBU compared to haplo at BMI 25-30 [hazard ratio (HR) 1.66-1.71, p < 0.05] and MUD transplants at a BMI of 25-45 (HR, 1.61-3.47, p < 0.05). The results demonstrated that NRM and survival outcomes are worse in overweight and obese transplant recipients (BMI ≥ 25) with one alternative donor type over MUD, although obesity does not appear to confer a uniform differential mortality risk with one donor type over the other. BMI may serve as a criterion for selecting a donor among the three (MUD, haplo and CBU) options, if matched sibling donor is not available.

Outcomes of Allogeneic Hematopoietic Cell Transplantation in T Cell Prolymphocytic Leukemia: A Contemporary Analysis from the Center for International Blood and Marrow Transplant Research.

T cell prolymphocytic leukemia (T-PLL) is a rare, aggressive malignancy with limited treatment options and poor long-term survival. Previous studies of allogeneic hematopoietic cell transplantation (alloHCT) for T-PLL are limited by small numbers, and descriptions of patient and transplantation characteristics and outcomes after alloHCT are sparse. In this study, we evaluated outcomes of alloHCT in patients with T-PLL and attempted to identify predictors of post-transplantation relapse and survival. We conducted an analysis of data using the Center for International Blood and Marrow Transplant Research database on 266 patients with T-PLL who underwent alloHCT between 2008 and 2018. The 4-year rates of overall survival (OS), disease-free survival (DFS), relapse, and treatment-related mortality (TRM) were 30.0% (95% confidence interval [CI], 23.8% to 36.5%), 25.7% (95% CI, 20% to 32%), 41.9% (95% CI, 35.5% to 48.4%), and 32.4% (95% CI, 26.4% to 38.6%), respectively. In multivariable analyses, 3 variables were associated with inferior OS: receipt of a myeloablative conditioning (MAC) regimen (hazard ratio [HR], 2.18; P < .0001), age >60 years (HR, 1.61; P = .0053), and suboptimal performance status, defined by Karnofsky Performance Status (KPS) <90 (HR, 1.53; P = .0073). Receipt of an MAC regimen also was associated with increased TRM (HR, 3.31; P < .0001), an elevated cumulative incidence of grade II-IV acute graft-versus-host disease (HR, 2.94; P = .0011), and inferior DFS (HR, 1.86; P = .0004). Conditioning intensity was not associated with relapse; however, stable disease/progression was correlated with increased risk of relapse (HR, 2.13; P = .0072). Both in vivo T cell depletion (TCD) as part of conditioning and KPS <90 were associated with worse TRM and inferior DFS. Receipt of total body irradiation had no significant effect on OS, DFS, or TRM. Our data show that reduced-intensity conditioning without in vivo TCD (ie, without antithymocyte globulin or alemtuzumab) before alloHCT was associated with long-term DFS in patients with T-PLL who were age ≤60 years or who had a KPS >90 or chemosensitive disease.

A calibrated Bayesian method for the stratified proportional hazards model with missing covariates.

Missing covariates are commonly encountered when evaluating covariate effects on survival outcomes. Excluding missing data from the analysis may lead to biased parameter estimation and a misleading conclusion. The inverse probability weighting method is widely used to handle missing covariates. However, obtaining asymptotic variance in frequentist inference is complicated because it involves estimating parameters for propensity scores. In this paper, we propose a new approach based on an approximate Bayesian method without using Taylor expansion to handle missing covariates for survival data. We consider a stratified proportional hazards model so that it can be used for the non-proportional hazards structure. Two cases for missing pattern are studied: a single missing pattern and multiple missing patterns. The proposed estimators are shown to be consistent and asymptotically normal, which matches the frequentist asymptotic properties. Simulation studies show that our proposed estimators are asymptotically unbiased and the credible region obtained from posterior distribution is close to the frequentist confidence interval. The algorithm is straightforward and computationally efficient. We apply the proposed method to a stem cell transplantation data set.

Competing risks regression models with covariates-adjusted censoring weight under the generalized case-cohort design.

A generalized case-cohort design has been used when measuring exposures is expensive and events are not rare in the full cohort. This design collects expensive exposure information from a (stratified) randomly selected subset from the full cohort, called the subcohort, and a fraction of cases outside the subcohort. For the full cohort study with competing risks, He et al. (Scand J Stat 43:103-122, 2016) studied the non-stratified proportional subdistribution hazards model with covariate-dependent censoring to directly evaluate covariate effects on the cumulative incidence function. In this paper, we propose a stratified proportional subdistribution hazards model with covariate-adjusted censoring weights for competing risks data under the generalized case-cohort design. We consider a general class of weight functions to account for the generalized case-cohort design. Then, we derive the optimal weight function which minimizes the asymptotic variance of parameter estimates within the general class of weight functions. The proposed estimator is shown to be consistent and asymptotically normally distributed. The simulation studies show (i) the proposed estimator with covariate-adjusted weight is unbiased when the censoring distribution depends on covariates; and (ii) the proposed estimator with the optimal weight function gains parameter estimation efficiency. We apply the proposed method to stem cell transplantation and diabetes data sets.

Autologous transplant vs chimeric antigen receptor T-cell therapy for relapsed DLBCL in partial remission.

The relative efficacy of autologous hematopoietic cell transplant (auto-HCT) vs chimeric antigen receptor T-cell (CAR-T) therapy in patients with diffuse large B-cell lymphoma (DLBCL) who achieve a partial remission (PR) after salvage chemotherapy is not known. Using the Center for International Blood & Marrow Transplant Research registry database, we identified adult patients with DLBCL who received either an auto-HCT (2013-2019) or CAR-T treatment with axicabtagene ciloleucel (2018-2019) while in a PR by computed tomography or positron emission tomography scan. We compared the clinical outcomes between the 2 cohorts using univariable and multivariable regression models after adjustment for relevant baseline and clinical factors. In the univariable analysis, the 2-year progression-free survival (52% vs 42%; P = .1) and the rate of 100-day nonrelapse mortality (4% vs 2%; P = .3) were not different between the 2 cohorts, but consolidation with auto-HCT was associated with a lower rate of relapse/progression (40% vs 53%; P = .05) and a superior overall survival (OS) (69% vs 47%; P = .004) at 2 years. In the multivariable regression analysis, treatment with auto-HCT was associated with a significantly lower risk of relapse/progression rate (hazard ratio = 1.49; P = .01) and a superior OS (hazard ratio = 1.63; P = .008). In patients with DLBCL in a PR after salvage therapy, treatment with auto-HCT was associated with a lower incidence of relapse and a superior OS compared with CAR-T. These data support the role of auto-HCT as the standard of care in transplant-eligible patients with relapsed DLBCL in PR after salvage therapy.

Predicting asymptomatic severe acute respiratory coronavirus virus 2 (SARS-CoV-2) infection rates of inpatients: A time-series analysis.

Asymptomatic SARS-CoV-2 infections are often difficult to identify because widespread surveillance has not been the norm. Using time-series analyses, we examined whether COVID-19 rates at the county level could predict positivity rates among asymptomatic patients in a large health system. Asymptomatic positivity rates at the system level and county-level COVID-19 rates were not associated.

Autologous and allogeneic hematopoietic cell transplantation for diffuse large B-cell lymphoma-type Richter syndrome.

Richter syndrome (RS) represents a transformation from chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) to aggressive lymphoma, most commonly diffuse large B-cell lymphoma (DLBCL), which is associated with a dismal prognosis. Patients with DLBCL-RS have poor outcomes with DLBCL-directed therapy; thus, consolidation with hematopoietic cell transplantation (HCT) has been used, with durable remissions observed. Studies reporting HCT outcomes in patients with DLBCL-RS have been small, have not evaluated the prognostic impact of cytogenetic risk factors, and were conducted prior to the era of novel targeted therapy of CLL/SLL. We performed a Center for International Blood and Transplant Research registry study evaluating outcomes after autologous HCT (auto-HCT; n = 53) and allogeneic HCT (allo-HCT; n = 118) in patients with DLBCL-RS treated in the modern era. More auto-HCT recipients were in complete response (CR) at HCT relative to allo-HCT recipients (66% vs 34%), whereas a higher proportion of allo-HCT recipients had 17p deletion (33% vs 7%) and had previously received novel agents (39% vs 10%). In the auto-HCT cohort, the 3-year relapse incidence, progression-free survival (PFS), and overall survival (OS) were 37%, 48%, and 57%, respectively. Among allo-HCT recipients, the 3-year relapse incidence, PFS, and OS were 30%, 43%, and 52%, respectively. In the allo-HCT cohort, deeper response at HCT was associated with outcomes (3-year PFS/OS, 66%/77% CR vs 43%/57% partial response vs 5%/15% resistant; P < .0001 for both), whereas cytogenetic abnormalities and prior novel therapy did not impact outcomes. In our study, HCT resulted in durable remissions in therapy-sensitive patients with DLBCL-RS treated in the era of targeted CLL/SLL therapy, including patients with high-risk features.