Outcomes of Antithymocyte Globulin-Post-Transplantation Cyclophosphamide-Cyclosporine-Based versus Antithymocyte Globulin-Based Prophylaxis for 10/10 HLA-Matched Unrelated Donor Allogeneic Hematopoietic Cell Transplantation

In 2015, dual T cell depletion with antithymocyte globulin (ATG) and post-transplantation cyclophosphamide (PTCy) combined with cyclosporine A (CsA) replaced our prior institutional graft-versus-host disease (GVHD) prophylaxis regimen of 4.5 mg/kg ATG, CsA, and mycophenolate mofetil (MMF) (ATG-based) in 10/10 HLA-matched unrelated donor (MUD) peripheral blood allogeneic hematopoietic stem cell transplantation (allo-HCT). The initial ATG dose of 4.5 mg/kg [ATG(4.5)/PTCy] was reduced to 2 mg/kg [ATG(2)/PTCy] in 2018. This study compares the results obtained from 444 adults undergoing MUD allo-HCT at our institution who received ATG(4.5)/PTCy (n = 127) or ATG(2)/PTCy (n = 223) with those who received ATG-based prophylaxis without PTCy (n = 84). The rates of grade II-IV and grade III-IV acute GVHD (aGVHD) at day +100 and moderate/severe chronic GVHD (cGVHD) at 1 year were 35.7%, 21.6%, and 14.7%, respectively, in patients receiving ATG-based prophylaxis without PTCy; 16.5%, 4.9%, and 4.3% in patients receiving ATG(4.5)/PTCy; and 23.3% (P = .004), 8.0% (P < .001), and 14.1% (P =.006) in patients receiving ATG(2)/PTCy. One-year overall survival (OS), nonrelapse mortality (NRM), and GVHD-free relapse-free survival (GRFS) were 69.8%, 25.3%, and 52.0%, respectively, for patients receiving ATG-based prophylaxis without PTCy; 82.7%, 17.3%, and 59.8% for patients receiving ATG(4.5)/PTCy; and 78.3% (P = .446), 14.7% (P = 101), and 56.2% (P = .448) for patients receiving ATG(2)/PTCy. On univariate analyses, the use of ATG(2)/PTCy was associated with a lower risk of NRM (hazard ratio, .54; P = .023) compared with the use of ATG-based prophylaxis without PTCy. ATG(2)/PTCy prophylaxis effectively prevents GVHD and is associated with comparable relapse risk, OS, and GRFS as seen with ATG(4.5)/PTCy and ATG-based prophylaxis without PTCy.

Pretransplant Blinatumomab Improves Outcomes in B Cell Acute Lymphoblastic Leukemia Patients Who Undergo Allogeneic Hematopoietic Cell Transplantation

BACKGROUND

Blinatumomab, a bispecific monoclonal antibody, effectively controls refractory B cell acute lymphoblastic leukemia (ALL) and promotes measurable residual disease (MRD) negativity. This study investigated the impact of pretransplant blinatumomab on allogeneic hematopoietic cell transplantation (HCT) outcomes in B cell ALL patients.

METHODS

We analyzed the effect of pretransplant blinatumomab on transplant outcomes of 117 adults undergoing allogeneic HCT for B cell ALL at Princess Margaret Hospital, Toronto, between 2010 and 2021. Outcomes assessed included overall survival (OS), graft-versus-host disease and relapse-free survival (GRFS), cumulative incidences of relapse (CIR), and nonrelapse mortality (NRM).

RESULTS

The median follow-up was 36 months. Thirty-one participants (26.5%) received blinatumomab. Blinatumomab group had higher proportions of individuals with high disease risk index, primary induction failure and was more likely to receive dual T cell depletion with antithymocyte globulin and post-transplant cyclophosphamide. Two-year OS, GRFS, NRM, and CIR in the blinatumomab and nonblinatumomab groups were, respectively: 65.4% versus 45.6% (P = .05), 42.2% versus 17.3% (P = .01), 3.2% versus 43.0% (P = .007) and 34.4% versus 14.4% (P = .02). Blinatumomab was associated with a lower incidence of day-100 grade 2 to 4 and grade 3 to 4 acute graft-versus-host disease (aGVHD): 27.5% versus 56.7% (P = .009), and 10.9% versus 34.7% (P = .04), respectively. Multivariate analysis confirmed the association between pretransplant blinatumomab and improved OS and NRM.

CONCLUSIONS

Pretransplant blinatumomab is associated with improved OS and lower risk of NRM in B cell ALL patients undergoing allogeneic HCT, likely reflecting lower burden of treatment-related toxicity in this population. Larger prospective trials are warranted to validate our findings.

Treosulfan- Versus Busulfan-based Conditioning in Allogeneic Hematopoietic Cell Transplantation for Myelodysplastic Syndrome: A Single-center Retrospective Propensity Score-matched Cohort Study

Treosulfan has shown promise in allogeneic hematopoietic cell transplantation (HCT) for its myeloablative properties and low toxicity. In this single-center retrospective propensity score-matched cohort study we compared treosulfan- and busulfan-based conditioning in allogeneic HCT for patients with myelodysplastic syndrome (MDS). This study included 138 adults who underwent allogeneic HCT for MDS or chronic myelomonocytic leukemia at Princess Margaret Hospital, Toronto, from 2015 to 2022. Using propensity score matching, we compared transplant outcomes between 2 well-matched cohorts who received conditioning with either fludarabine-treosulfan (FT) (n = 46) or fludarabine-busulfan with total body irradiation (FBT200) (n = 92). A scoring system based on patient age, Karnofsky performance score, and hematopoietic cell transplant comorbidity index was used to assign patients based on fitness to low-dose (30 g/m2) or high-dose (42 g/m2) treosulfan: 32 (69.6%) received high-dose treosulfan. The racial composition of the 2 groups was similar, with 27.2% and 21.7% of FBT200 and FT recipients, respectively, identifying as non-Caucasian (P = .61). Primary outcomes were analyzed at a median follow-up of 747 days. Of all participants, 116 (84.0%) received graft-versus-host disease (GVHD) prophylaxis with post-transplant cyclophosphamide (PTCY) and antithymocyte globulin (ATG). Patients who received FT had a superior 2-year overall survival (OS) compared to those who received FBT200: 66.9% (95% confidence interval (CI): 46.1 to 81.2) versus 44.5% (95% CI: 34 to 54.4), hazard ratio (HR): 0.43, 95% CI: 0.22 to 0.84 (P = .013). In multivariate analysis (MVA), only the use of fresh grafts (P = .02) and FT (P = .01) were associated with improved OS. FT was associated with superior 2-year relapse-free survival (RFS) compared to FBT200: 63.1% (95% CI: 42.6 to 77.9) versus 39.1% (95% CI: 29.1 to 49.1), HR: 0.44 (95% CI: 0.24 to 0.81), P = .008. In MVA, the use of fresh grafts (P = .03) and FT (P = .009) were associated with improved RFS. Recipients of FT demonstrated superior 2-year graft-versus-host disease relapse-free survival (GRFS) compared to those who received FBT200: 57.4% (95% CI: 37.8 to 72.8) versus 35.1% (95% CI: 25.5 to 45). In MVA, only FT was associated with superior GRFS (P = .02). FT recipients exhibited markedly superior 1-year event-free survival compared to recipients of FBT200 in univariate analysis (40.3% (95% CI: 25.9 to 54.2) versus 9.2% (95% CI: 4.4 to 16.3), HR: 0.47 (95% CI: 0.30 to 0.72), P < .001) and MVA (P = .004). FT was associated with lower 1-year nonrelapse mortality compared to FBT200 in univariate analysis (9.9% (95% CI: 3.0 to 21.8) versus 29.7% (95% CI: 20.6 to 39.3), HR: 0.41 (95% CI: 0.17 to 0.96), P = .04) and MVA (P = .04). Our study utilized propensity score matching to demonstrate superiority of treosulfan- over busulfan-based conditioning in stem cell transplantation of patients with MDS and is the first to evaluate the performance of treosulfan-based conditioning in combination with ATG and PTCY. As such, it contributes to the increasing body of evidence supporting the safety of treosulfan, even at the dose of 42 g/m2.

Dual T cell depletion for graft versus host disease prevention in peripheral blood haploidentical hematopoietic cell transplantation for adults with hematological malignancies

The ideal immunosuppressive agents to complement post-transplant cyclophosphamide (PTCy) in PBSC-based haploidentical hematopoietic cell transplantation (haplo-HCT) remain debated. This study looks at our experience with ATG-PTCy-Cyclosporine (CsA) prophylaxis in PB haplo-HCT since 2015. Between October 2015 and December 2021, 157 adults underwent haploidentical hematopoietic cell transplantation (haplo-HCT) using a GVHD prophylaxis regimen comprising rabbit-ATG, PTCy, and CsA. Among these patients, 76.4% received a total ATG dose of 4.5 mg/kg, and 23.5% received 2 mg/kg. T-cell replete peripheral blood stem cell (PBSC) grafts were infused on day 0. The study reported a median follow-up of 32 months (range 0.3-61.64) for survivors. The cumulative incidence of grade II-IV and grade III-IV acute GVHD at day +100 was 26.3% and 9.5%, respectively. Moderate/severe chronic GVHD at 1 year was 19.9%. The 2-year overall survival (OS) was 49.4%, with a relapse-free survival (RFS) of 44.6%. In multivariate analysis, older patients, and those with high/very-high disease risk indices (DRI) were at higher risk for worse OS and higher non-relapse mortality (NRM). The study confirms that using PTCy and ATG (4.5 mg/kg), alongside CsA is safe and effective in preventing GVHD when using peripheral blood as the stem cell source in haploidentical hematopoietic cell transplantation (haplo-HCT).

Late-onset Pneumocystis jirovecii pneumonia post-allogeneic stem cell transplantation after time-dependent discontinuation of prophylaxis

INTRODUCTION

Pneumocystis jirovecii pneumonia (PJP) is a rare complication of hematopoietic stem cell transplantation (HSCT). Primary prophylaxis for 6-12 months post-HSCT is the standard approach. However, there is no consensus regarding the optimal duration of prophylaxis.

METHODS

We identified patients who developed PJP more than 1-year post-HSCT. All patients had previously received 12 months of PJP prophylaxis. PJP was diagnosed based on clinical findings and the detection of P. jirovecii in bronchoalveolar lavage (BAL) using polymerase chain reaction (PCR). The CD4+ T-cell percentage was determined using flow cytometry. Data expressed as median (interquartile range).

RESULTS

Ten patients developed PJP at 17.5 months (16-24 months) post-HSCT. PJP diagnosis occurred 5.5 months (3-15 months) after discontinuing prophylaxis. Eight patients received anti-thymocyte globulin (ATG) as graft versus host disease (GVHD) prophylaxis. At diagnosis, only one patient had lymphopenia; all patients had CD4+ T-lymphocyte counts ≥0.2 × 109 /L (median 0.337 × 109 /L). Three patients had concomitant bacterial infections. The clinical presentation was mild; only three required hospitalization, none of them required intensive care and there were no deaths.

CONCLUSION

There is a need to develop risk-adapted prophylactic strategies in the contemporary era using ATG-based GVHD prophylaxis.

Donor-Derived Malignancy and Transplantation Morbidity: Risks of Patient and Donor Genetics in Allogeneic Hematopoietic Stem Cell Transplantation

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a key treatment option for hematologic malignancies (HMs), although it carries significant risks. Up to 30% of patients relapse after allo-HSCT, of which up to 2% to 5% are donor-derived malignancies (DDMs). DDMs can arise from a germline genetic predisposition allele or clonal hematopoiesis (CH) in the donor. Increasingly, genetic testing reveals that patient and donor genetic factors contribute to the development of DDM and other allo-HSCT complications. Deleterious germline variants in CEBPA, DDX41, GATA2, and RUNX1 predispose to inferior allo-HSCT outcomes. DDM has been linked to donor-acquired somatic CH variants in DNMT3A, ASXL1, JAK2, and IDH2, often with additional new variants. We do not yet have evidence to standardize donor genetic sequencing prior to allo-HSCT. The presence of hereditary HM disorders should be considered in patients with myeloid malignancies and their related donors, and screening of unrelated donors should include family and personal history of cytopenia and HMs. Excellent multidisciplinary care is critical to ensure efficient timelines for screening and necessary discussions among medical oncologists, genetic counselors, recipients, and potential donors. After allo-HSCT, HM relapse monitoring with genetic testing effectively results in genetic sequencing of the donor, as the transplanted hematopoietic system is donor-derived, which presents ethical challenges for disclosure to patients and donors. We encourage consideration of the recent National Marrow Donor Program policy that allows donors to opt-in for notification about detection of their genetic variants after allo-HSCT, with appropriate genetic counseling when feasible. We look forward to prospective investigation of the impact of germline and acquired somatic genetic variants on hematopoietic stem cell mobilization/engraftment, graft-versus-host disease, and DDM to facilitate improved outcomes through knowledge of genetic risk.

Multiplex proteomics in the identification of potential biomarkers of very severe sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD) in allogeneic hematopoietic cell transplant patients treated with defibrotide

Introduction Despite well-established clinical criteria for diagnosis of SOS/VOD following allogeneic HCT, there is a lack of established diagnostic protein biomarkers. Methods Prospective samples were collected from patients with very severe SOS/VOD at diagnosis and days +3, +7, +14, and +30 post-initiation of defibrotide. Samples from age-matched controls with no VOD were collected at day +14, +30, +60, +90 and +180 following allogeneic HCT. Serum samples were analyzed for 2925 protein levels by antibody-based proximity extension assay (PEA). Mean differences in the log-transformed abundance values were compared using t-tests in a volcano plot. Results Five patients with very severe SOS/VOD and five control patients were compared. Ten proteins were identified that showed a statistically significant and log-transformed 3-fold increase in concentration. They were CALCA, CCL20, GPR37, IGFBP4, IL1RL1, SLC39A14, SPINK4, FABP3, MYL3, and CHCHD10. Four different proteins, namely CD83, LAIR2, CD7, and HEM6 showed a significant decrease with defibrotide treatment. SOS/VOD resolved in 80% (n=4) of patients, while one patient deceased due to SOS/VOD. Conclusion PEA technology identified 10 proteins that were significantly elevated in patients with very severe SOS/VOD. Prospective studies in a larger cohort using this technology may be able to conclusively identify diagnostic protein biomarkers for SOS/VOD.

Letermovir prophylaxis for cytomegalovirus reactivation in allogeneic hematopoietic cell transplant recipients: Single center Canadian data

BACKGROUND

Cytomegalovirus (CMV) is associated with morbidity and mortality following allogeneic hematopoietic cell transplantation (alloHCT). Letermovir is a novel antiviral agent that prevents CMV reactivation in alloHCT patients, with limited data regarding influence on post-alloHCT outcomes.

METHODS

We retrospectively examined 273 alloHCT recipients, 158 in the non-letermovir cohort (NLC), and 115 in the cohort using letermovir prophylaxis (LC). Patients that received letermovir were CMV-seropositive and met criteria for high risk of CMV reactivation.

RESULTS

Median start of letermovir was 21 days post-alloHCT, median duration of prophylaxis was 86 days. Letermovir prophylaxis demonstrated a statistically significant reduction in first CMV reactivation (at 200 days post 63.9% in the NLC vs. 35.7% in the LC; p < .001). On univariate analysis at 1 year, overall survival (OS) for NLC was 79.6% and 79.5% for LC (p = .54). Non relapse mortality (NRM) at 1 year for NLC was 12% and 12.3% for LC (p = .69). Cumulative incidence of relapse (CIR) at 1 year was 13.9% for NLC versus 17.1 for the LC (p = .27). On multivariable analysis, there was no significant difference between the two cohorts for OS, NRM, and CIR.

CONCLUSIONS

Letermovir prophylaxis started at day +21 post-alloHCT reduced CMV reactivation, with no impact on posttransplant outcomes.

Propensity Score Matching Analysis Comparing the Efficacy and Steroid Tapering Benefit of Extracorporeal Photopheresis to Best Available Therapy in Third-Line or Beyond Treatment for Chronic GvHD

Graft-versus host disease (GVHD) is one of the major limitations to allogeneic hematopoietic stem cell transplantation (HCT). Although corticosteroids with calcineurin inhibitors are established first line-therapy for chronic graft-versus-host disease (cGVHD), approximately one-half of cGVHD patients are refractory to corticosteroid therapy. The goal of the present study was to compare treatment outcomes of patients treated with extracorporeal photopheresis (ECP) and best available therapy (BAT) as third-line or beyond treatment for cGVHD. Using propensity score matching (PSM), treatment outcomes were compared between ECP-treated patients (n = 74) and a historical cohort of cGVHD patients treated with BAT (n = 132). By adjusting for unbalanced risk factors between the groups, including GVHD severity at the start of therapy, acute GVHD history, and baseline corticosteroid dose, 62 patients were balanced and selected for PSM. In the PSM cohort, the ECP group showed a 12-month failure-free survival (FFS) rate of 70.1% versus 32.5% in the BAT group (P < .0001; hazard rate [HR], .214), and 93.1% 12 months' overall survival (OS) rate of 93.1% versus 68.1% in the BAT group (P = .0249; HR, .3811); multivariate analysis confirmed ECP's superior FFS and OS compared with BAT. Generalized linear model analysis showed faster tapering of corticosteroids and higher rates of prednisone discontinuation in the ECP versus BAT PSM groups in the first 6 months. The ECP group also had a higher percentage of prednisone discontinuation, by 6% at month 0, by 14.9% at month 3, and by 22.5% at month 6. The current study demonstrates superior FFS, OS, and steroid tapering efficacy for ECP compared with BAT as third-line therapy or beyond in cGVHD patients.

Allogeneic hematopoietic cell transplantation for blastic plasmacytoid dendritic cell neoplasm: a CIBMTR analysis

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare hematological malignancy with a poor prognosis and considered incurable with conventional chemotherapy. Small observational studies reported allogeneic hematopoietic cell transplantation (allo-HCT) offers durable remissions in patients with BPDCN. We report an analysis of patients with BPDCN who received an allo-HCT, using data reported to the Center for International Blood and Marrow Transplant Research (CIBMTR). We identified 164 patients with BPDCN from 78 centers who underwent allo-HCT between 2007 and 2018. The 5-year overall survival (OS), disease-free survival (DFS), relapse, and nonrelapse mortality (NRM) rates were 51.2% (95% confidence interval [CI], 42.5-59.8), 44.4% (95% CI, 36.2-52.8), 32.2% (95% CI, 24.7-40.3), and 23.3% (95% CI, 16.9-30.4), respectively. Disease relapse was the most common cause of death. On multivariate analyses, age of ≥60 years was predictive for inferior OS (hazard ratio [HR], 2.16; 95% CI, 1.35-3.46; P = .001), and higher NRM (HR, 2.19; 95% CI, 1.13-4.22; P = .02). Remission status at time of allo-HCT (CR2/primary induction failure/relapse vs CR1) was predictive of inferior OS (HR, 1.87; 95% CI, 1.14-3.06; P = .01) and DFS (HR, 1.75; 95% CI, 1.11-2.76; P = .02). Use of myeloablative conditioning with total body irradiation (MAC-TBI) was predictive of improved DFS and reduced relapse risk. Allo-HCT is effective in providing durable remissions and long-term survival in BPDCN. Younger age and allo-HCT in CR1 predicted for improved survival, whereas MAC-TBI predicted for less relapse and improved DFS. Novel strategies incorporating allo-HCT are needed to further improve outcomes.

Choosing Between Older Matched Sibling Donor and Younger Matched Unrelated Donor in Allogeneic Hematopoietic Cell Transplantation: Comparison of Clinical Outcomes in Acute Myeloid Leukemia and Myelodysplastic Syndrome

The choice between an older matched sibling donor (MSD) and a younger matched unrelated donor (MUD) in allogeneic hematopoietic cell transplantation (HCT) remains a subject of ongoing debate. In this single-center retrospective study of 377 patients who received peripheral blood stem cell (PBSC) transplants for acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS), we compared outcomes of 85 patients who received grafts from MSDs age >60 years and 292 patients who received grafts from MUDs age <30 years. Compared to recipients of MSD transplants, recipients of MUD transplants were younger and more likely to receive dual T cell depletion (TCD), a higher CD34+ cell dose, and a fresh graft. Recipients of MSD transplants were maintained on immunosuppressive therapy longer than those who received MUD grafts. We found no differences in overall survival, relapse-free survival, graft-versus-host disease (GVHD)-free and relapse-free survival, nonrelapse mortality, relapse, engraftment, graft failure, and acute GVHD between recipients of MSD grafts and recipients of MUD grafts. We report a higher 30-day incidence, but not 1-year incidence, of bloodstream infections among recipients of MUD transplants compared to subjects who received their grafts from a MSD. The incidence of moderate-severe chronic GVHD was higher in MSD graft recipients compared with MUD graft recipients in univariate analysis, but not in multivariate analysis. Although this difference could reflect the greater use of dual TCD, known to be associated with very low rates of chronic GVHD in MUD transplant recipients, the incidence of moderate-severe chronic GVHD was no different between MSD and MUD transplant recipients following propensity score matching, suggesting that other variables could be responsible. Taken together, our data suggest that in patients with AML or MDS who receive PBSC transplants, such factors as convenience, ease of access, and costs should be considered when selecting an older MSD over a younger MUD.

HCT frailty scale for younger and older adults undergoing allogeneic hematopoietic cell transplantation

The HCT Frailty Scale is an easy prognostic tool composed of (a) Clinical Frailty Scale; (b) Instrumental Activities of Daily Living; (c) Timed-up-and-Go test; (d) Grip Strength; (e) Self-Health Rated Questionnaire; (f) Falls tests; (g) Albumin and C-reactive protein levels. This scale was designed to classify allogeneic hematopoietic cell transplant (alloHCT) candidates into fit, pre-frail and frail groups, irrespective of age. This study evaluates the ability of this frailty classification to predict overall survival (OS) and non-relapse mortality (NRM) in adult patients of all ages, in a prospective sample of 298 patients transplanted between 2018 and 2020. At first consultation, 103 (34.6%) patients were fit, 148 (49.7%) pre-frail, and 47 (15.8%) were frail. The 2-year OS and NRM of the three groups were 82.9%, 67.4%, and 48.3% (P < 0.001), and 5.4%, 19.2%, and 37.7% (P < 0.001). For patients younger than 60 years (n = 174), the 2-year OS and NRM of fit, pre-frail, and frail groups were 88.4%, 69.3% and 53.1% (P = 0.002), and 5.8%, 22.8%, and 34.8% (P = 0.005), respectively; and in patients older than 60 (n = 124), OS and NRM were 75.5%, 63.8% and 41.4% (P = 0.006), and 4.9%, 16.4%, and 42.1% (P = 0.001). In conclusion, frailty predicted worse transplant outcomes in both younger and older adults.

Prognostic implication of pre-transplant FEV1 on long-term outcomes following allogeneic hematopoietic stem cell transplantation

BACKGROUND

Pre-transplant pulmonary function testing (PFT) is essential before allogeneic hematopoietic stem cell transplant (HCT), yet the optimal cutoff value for affecting transplant outcomes remains poorly defined.

STUDY DESIGN

Retrospective analysis of pre-HCT PFT data from 605 consecutive patients at the Princess Margaret Cancer Centre between January 1, 2004 and December 31, 2013 used binary recursive partitioning to identify cutoff values for overall survival (OS) as an endpoint of transplant outcomes. These values were compared to HCT comorbidity index (HCT-CI) FEV1 cutoffs for OS, cumulative incidence of relapse and non-relapse mortality.

RESULTS

FEV1  ≥ 81% was the identified cutoff point. The OS rate at 3 years showed 49.8% (FEV1  ≥ 81%) vs. 36.6% (<81%, p < .001). For HCT-CI cutoffs, the OS rate at 3 years for FEV1  ≥ 80%, 66%-80% and ≤65% were 49.0%, 38.1% and 37.6% (p = .011), respectively. Multivariate analysis confirmed that FEV1  ≥ 81% predicted reduced mortality (HR 0.682, p = .001). Subgroup analysis showed both FEV1  ≥ 81% and FEV1 by HCT-CI cutoffs may stratify patients according to OS and NRM risk in subgroups receiving myeloablative, but not reduced intensity conditioning.

CONCLUSION

FEV1  ≥ 81% can predict OS and NRM in our cohort and is potentially simpler when risk stratifying patients undergoing allogeneic HCT, particularly those receiving myeloablative conditioning.

Single centre retrospective analysis of extracorporeal photopheresis (ECP) therapy in patients heavily pre-treated for chronic graft-versus-host disease (cGvHD) with steroid failure

BACKGROUND

Extracorporeal photopheresis (ECP) is recommended as a second- or later-line therapy for chronic GvHD (cGvHD). Benefits include reasonable response with avoidance of intense systemic immunosuppression, which can translate into lowering the risk of systemic toxicity and opportunistic infection.

METHODS

We evaluated 75 patients treated with ECP for cGvHD from 2007 to 2021 at Princess Margaret Cancer Centre, and analyzed overall response rate (ORR) and clinical benefit (CB) at 3, 6 and 12 months plus other long-term treatment outcomes.

RESULTS

With a median follow-up of 72 months, a gradual increase in ORR was noted over time: 21% (16 out of 75 patients), 57% (36/63) and 70% (32/46) at month 3, 6 and 12, respectively. Gradual increase in CB was also observed over time with CB rate of 23% (17/75), 62% (39/63), and 76% (35/46) at months 3, 6 and 12, respectively. A total of 27 failures (36%) were noted, due to: 1) ECP resistance requiring switch to other therapy (n = 14, 19%), 2) non-relapse mortality (n = 10, 13%), 3) relapse of primary disease (n = 1, 1%) or 4) ECP procedure-related complication (n = 1, 1%, line infection), with 20 deaths (27%) observed. Failure-free survival (FFS) and overall survival (OS) rates were 68.3% and 85.9% at 12 months, respectively. After starting ECP, the proportions of patients who completely discontinued steroids were 17%, 32%, and 64% at months 3, 6 and 12, respectively.

CONCLUSION

ECP is an effective treatment option for heavily pre-treated cGvHD patients.

Influence of conditioning regimen intensity on outcomes post-allogeneic hematopoietic cell transplantation for acute myeloid leukemia in complete morphological remission

INTRODUCTION

The literature comparing outcomes between myeloablative (MAC) and reduced intensity conditioning (RIC) for acute myeloid leukemia (AML) is conflicting.

METHODS

We retrospectively analyzed 451 patients who underwent allogenic hematopoietic cell transplantation (alloHCT) for AML in complete remission (CR) with either RIC (n = 331) or MAC (n = 120) with the use of dual T-cell depletion as graft-versus-host disease (GVHD) prophylaxis.

RESULTS

Univariate analysis demonstrated nonrelapse mortality (NRM) at 2 years was 19.1% for MAC and 22.5% for RIC (p = .44). Two-year cumulative incidence of relapse (CIR) was 19.8% for MAC and 24.5% for RIC (p = .15). Two-year overall survival (OS) was 61% and 53% for MAC and RIC, respectively (p = .02). Two-year graft-versus-host disease relapse-free survival (GRFS) was 40.8% for MAC and 33.7% for RIC (p = .30). A propensity score-matched analysis was done matching patients for age, HLA match, in vivo T-cell depletion, and Disease Risk Index (DRI). Two-year OS was 67% for MAC, 66% for RIC (p = .95). A subgroup analysis identified that matched related donor transplants benefit from MAC with OS at 2 years 82.6% versus 57.3% for RIC (p = .006).

CONCLUSIONS

In the matched-related donor setting, MAC regimens may offer superior survival. Overall, for our cohort of predominantly in vivo T-cell depleted patients the outcomes of MAC and RIC were similar.

Machine learning for the prediction of survival post-allogeneic hematopoietic cell transplantation: A single-center experience

INTRODUCTION

Prediction of outcomes following allogeneic hematopoietic cell transplantation (HCT) remains a major challenge. Machine learning (ML) is a computational procedure that may facilitate the generation of HCT prediction models. We sought to investigate the prognostic potential of multiple ML algorithms when applied to a large single-center allogeneic HCT database.

METHODS

Our registry included 2697 patients that underwent allogeneic HCT from January 1976 to December 2017, 45 pre-transplant baseline variables were included in the predictive assessment of each ML algorithm on overall survival (OS) as determined by area under the curve (AUC). Pre-transplant variables used in the EBMT machine learning study (Shouval et al, 2015) were used as a benchmark for comparison.

RESULTS

On the entire dataset, the random forest (RF) algorithm performed best (AUC 0.71±0.04) compared to the second-best model, logistic regression (LR) (AUC=0.69±0.04) (p<0.001). Both algorithms demonstrated improved AUC scores using all 45 variables compared to the limited variables examined by the EBMT study. Survival at 100 days post-HCT using RF on the full dataset discriminated patients into different prognostic groups with different 2-year OS (p<0.0001). We then examined the ML methods that allow for significant individual variable identification, including LR and RF, and identified matched related donors (HR=0.49, p<0.0001), increasing TBI dose (HR=1.60, p=0.006), increasing recipient age (HR=1.92, p<0.0001), higher baseline Hb (HR=0.59, p=0.0002) and increased baseline FEV1 (HR=0.73, p=0.02), among others.

CONCLUSION

The application of multiple ML techniques on single center allogeneic HCT databases warrants further investigation and may provide a useful tool to identify variables with prognostic potential.

Weight loss post-allogeneic stem cell transplant is associated with increased transplant-related mortality

PURPOSE

Allogeneic stem cell transplant (allo-HSCT) patients are at risk of malnutrition and weight loss from impaired oral intake resulting from gastrointestinal toxicities, dysgeusia, and psychological effects.

METHODS

A retrospective review of 264 adult patients transplanted at Princess Margaret Cancer Centre who achieved relapse-free survival up to 3 months after allo-HSCT was performed.

RESULTS

Overall incidence of patients who experienced WL (WL) ≥ 10% from HSCT to 3-month post-transplant was 45.9% and from HSCT to 6 months was 56.6%. Patients with ≥ 10% WL from allo-HSCT at 3 months and 6 months had similar 2-year overall survival (OS) compared to those with < 10% WL, 55.7% vs 62.8% (HR = 1.38, p = 0.11) and 71.1% vs 77.2% (HR = 1.37, p = 0.27), respectively. Patients with ≥ 10% WL 3 and 6 months from allo-HSCT also had similar 2-year relapse-free survival (RFS) compared to those with < 10% WL, 48.1% vs 55.8% (HR = 1.26, p = 0.22), and 62.7% vs 69.8% (HR = 1.29, p = 0.31), respectively. The 2-year transplant-related mortality (TRM) was higher for those with ≥ 10% WL from allo-HSCT to 3 months, 35.4% vs 16.9% (HR = 2.39, p = 0.0007) and 6 months, 22% vs 8% (HR = 3.1, p = 0.0034). Although statistical significance was not observed for OS or RFS, patients who experienced ≥ 10% WL 3- and 6-months post allo-HSCT experienced higher 2-year TRM. These results highlight the importance of early intervention and close monitoring of weight post allo-HSCT.

CONCLUSION

Approaches to WL post allo-HSCT should be multifaceted and include members of the interdisciplinary team in order to decrease TRM.

Interaction Between High-Dose Intravenous Busulfan and Post-Transplantation Cyclophosphamide on Hemorrhagic Cystitis After Allogeneic Hematopoietic Cell Transplantation

This study investigates the incidence and predictors of hemorrhagic cystitis (HC) in 960 adults undergoing allo- hematopoietic stem cell transplantation. Two hundred fifty-two (26.5%) patients received myeloablative conditioning regimens, and 81.4% received high-dose intravenous busulfan (HD Bu). Six hundred ninety-five (72.4%) patients received post-transplantation cyclophosphamide (PTCY)-based prophylaxis, and 91.4% additionally received anti-thymocyte globulin (ATG) and Cyclosporine A (CsA) (PTCY-ATG-CsA). Two hundred twenty-eight (23.8%) patients developed HC. The day 100 cumulative incidences of grades 2-4 and 3-4 HC were 11.1% and 4.9%. BK virus was isolated in 58.3% of urinary samples. Using HD BU myeloablative regimens increased the risk for grade 2-4 HC (hazard ratio [HR] = 1.97, P = .035), and HD BU combined with ATG-PTCY-CsA increased this 4 times (HR = 4.06, P < .001) for grade 2-4 HC compared to patients who received neither of these drugs. A significant correlation was documented between grade II-IV acute graft-versus-host disease and grade 2-4 HC (HR = 2.10, P < .001). Moreover, patients with BK-POS grade 2-4 HC had lower 1-year overall survival (HR = 1.51, P = .009) and higher non-relapse mortality (HR = 2.31, P < .001), and patients with BK-NEG grade 2-4 HC had comparable post-transplantation outcomes. In conclusion, intravenous HD Bu was identified as a predictor for grade 2-4 HC. Moreover, when HD Bu was combined with PTCY-ATG-CsA, the risk increased 4-fold. Based on the results provided by this study, preventing the onset of HC, especially in high-risk patients, is mandatory because its presence significantly increases the risk for mortality.

A Single-center, Real-world Experience of Chronic GVHD Treatment Using Ibrutinib, Imatinib, and Ruxolitinib and its Treatment Outcomes

BACKGROUND

Chronic graft-versus-host disease (cGVHD) is a common cause of morbidity and mortality following allogeneic hematopoietic stem cell transplantation. Tyrosine kinase inhibitors (TKIs), including ruxolitinib, imatinib, and ibrutinib, have shown promising efficacy in cGVHD treatment.

METHOD

A total of 43 patients who developed cGVHD and received at least one line of TKI therapy for cGVHD treatment were evaluated retrospectively. The overall response, clinical benefit (CB), corticosteroid dose reduction, failure-free survival (FFS), and overall survival (OS) were assessed.

RESULT

A total of 62 lines of TKI therapy were evaluated, including ruxolitinib (n = 18), ibrutinib (n = 13), and imatinib (n = 31). With a 12-month median follow-up duration, 19/58 (32.8%), 20/41 (48.7%), and 17/29 (58.6%) responded to TKI therapy at 3, 6, and 12 months, respectively. The CB was observed in 80% of patients over time, allowing prednisone dose reduction in all 3 TKIs. The FFS rate at 12 months was higher in the imatinib (71%) and ruxolitinib groups (67%) than in the ibrutinib group (46%), while the OS rate at 12 months was similar among the three groups at 96%-100% in patients. In the sclerotic GVHD patient subgroup (n = 39), the overall response rate gradually increased over time. Ruxolitinib appeared to be as effective as imatinib and gradually improved the photographic range of motion score in sclerotic GVHD patients.

CONCLUSION

TKI drugs ruxolitinib, imatinib, and Ibrutinib are effective and feasible for cGVHD treatment. Ruxolitinib is as effective as imatinib for sclerotic GVHD.

Impact of hematopoietic cell transplant frailty scale on transplant outcome in adults

This prospective study designs an HCT Frailty Scale to classify alloHCT candidates into groups of frail, pre-frail, and fit, and to be implemented in the first consultation at no additional cost. The present scale is composed of the following eight variables: Clinical Frailty Scale, Instrumental Activities of Daily Living, Timed Up and Go Test, Grip Strength, Self-Health Rated, Falls, Albumin, and C-Reactive Protein. The Frailty score of a patient is the weighted sum of scores for each item, with weights assigned according to the hazard ratios of a multivariable Cox proportional hazards model estimated and validated with data on OS as the dependent variable, and the scores of the eight variables as explanatory ones, from 298 adults split into training (n = 200) and validation (n = 98) sets. For clinical use, the scale scores were transformed into three categories: scale score ≤1: fit; 1<scale score ≤5.5: pre-frail; scale score >5.5 frail. The estimated probabilities of 1-year OS in each group of frailty, were, respectively: 83.7%, 48.5%, and 16.5% (p < 0.001). In the validation cohort, the respective values were 90.3%, 69.5%, and 46.2% (p < 0.001). Pending further external validations, the HCT Frailty Scale is a low cost-highly informative prognostic signal of outcomes at the pre-transplant stage.

Mutational profile, outcomes, and impact of allogeneic hematopoietic stem cell transplantation in adult patients with acute myeloid leukemia and inconclusive cytogenetic analysis

BACKGROUND

Inconclusive cytogenetic analysis (IC) at baseline has been reported as a predictor of poor prognosis in patients with acute myeloid leukemia (AML). The mutational profile in this group of patients, and its impact on outcomes have not been reported.

METHODS

We retrospectively analyzed adult patients (≥18 years) with newly diagnosed AML treated with intensive induction chemotherapy between 2015 and 2019. Patients with any documented cytogenetic abnormalities were excluded. Targeted next generation sequencing (NGS) was performed in all patients. Baseline characteristics, mutation profile, and outcomes were compared between patients with normal cytogenetics(NC) and those with IC.

RESULTS

Sixty-one patients (males 39.3%; median age 59 years) had IC at diagnosis. The proportion of patients with mutations in genes with proven prognostic impact were not different between AML patients with IC and NC. AML patients with NC were more likely to harbor the prognostically favorable NPM1^mut /FLT3-ITD^wt mutational combination conferring "favorable" risk status. As a result, a larger proportion of patients in the IC group underwent allogeneic hematopoietic stem cell transplantation (allo HCT; 54.1% vs. 39.6%; p = .02). The 2-year RFS (55.9% vs. 58.5%; p = .29) and OS (61.9% vs. 66.9%; p = .48) were similar in IC and NC patients. There was no difference in survival of patients who underwent allo HCT when compared with patients who did not (p = .99).

CONCLUSIONS

Inconclusive cytogenetic analysis may not be an independent prognostic indicator in AML. In such patients, molecular abnormalities detected through NGS or whole genome sequencing are more likely to be informative.

Clonal hematopoiesis in the donor does not adversely affect long-term outcomes following allogeneic hematopoietic stem cell transplantation: result from 13-year followup

Donor clonal hematopoiesis may be transferred to the recipient through allogeneic hematopoietic stem cell transplantation (HCT), but the potential for adverse long-term impact on transplant outcomes remains unknown. A total of 744 samples from 372 recipients who received HCT and the corresponding donors were included. Bar-coded error-corrected sequencing using a modified molecular inversion probe capture protocol was performed, which targeted 34 genes covering mutations involved in clonal hematopoiesis with indeterminate potential (CHIP) and other AML-related mutations. A total of 30 mutations were detected from 25 donors (6.7%): the most frequently mutated gene was TET2 (n=7, 28%), followed by DNMT3A (n=4, 16%), SMC3 (n=3, 12%) and SF3B1 (n=3, 12%). With a median follow-up duration of 13 years among survivors, the presence of CHIP in the donor was not associated with recipient overall survival (p=0.969), relapse incidence (p=0.600) or non-relapse mortality (p=0.570). Donor CHIP did not impair neutrophil (p=0.460) or platelet (p=0.250) engraftment, the rates of acute (p=0.490), or chronic graft-vs-host disease (p=0.220). No significant difference was noted for secondary malignancy following HCT between the two groups. The present study suggests that the presence of CHIP in allogeneic stem donors does not adversely affect transplant outcomes after HCT. Accordingly, further study is warranted to reach a clearer conclusion on whether molecular profiling to determine the presence of CHIP mutations is necessary for the pre-transplant evaluation of donors prior to stem cell donation.

Multiplex proteomics using proximity extension assay for the identification of protein biomarkers predictive of acute graft-vs.-host disease in allogeneic hematopoietic cell transplantation

OBJECTIVES

Allogeneic hematopoietic cell transplantation (HCT) is associated with acute graft-vs.-host disease (aGVHD). The presented study applied a novel multiplex antibody-based proximity extension assay (PEA) proteomic platform that can detect thousands of serum proteins simultaneously for the identification of potential biomarkers of aGVHD.

METHODS

Serum samples from 28 patients who underwent allogeneic HCT for acute myeloid leukemia (AML) were analyzed; 17 were diagnosed with grade II-IV aGVHD while 11 patients were not. Samples collected on day -6, day 0, +14, +30, +60 and +90 post-HCT were analyzed for the relative concentrations of 552 proteins. The concentration of each protein from baseline to the closest time point before onset of aGVHD, or to the latest time point in control patients, was documented.

RESULTS

Individualized analysis identified 26 proteins demonstrating ≥3-fold increase at aGVHD onset compared to baseline, eliminating proteins with a similar increase in controls. Another approach used paired t-testing and logistic regression that identified a four-marker panel, including SLAMF7, IL-1ra, BTN3A2 and DAB2, where individual log-likelihood ratios ranged from 3.99 to 8.15 (logistic regression, p=0.004-0.046). When combined, the four-marker panel demonstrated an area under the curve (AUC) of 0.90 (95% CI: 0.78-1.00; p=0.0006) with high negative predictive value of 81.8% and positive predictive value of 86.7%. All four markers play a physiological role in immune regulation. Among these, three were also present in the individualized analysis (SLAMF7, IL-1ra and BTN3A2).

CONCLUSIONS

We conclude that serum proteins identified using multiplex proteomics, particularly SLAMF7, IL-1ra, BTN3A2 and DAB2, may potentially predict aGVHD.

Improved donor chimerism in relapse myelofibrosis post allogenic stem cell transplant with azacitidine and oral decitabine-First case report

To date, allogenic stem cell transplant (ASCT) remains the only potential curative option for patients with primary myelofibrosis (PMF). However, relapse rates and associated mortality remain a concern. A second ASCT may not be feasible due to advancing age, declined functional status, donor unavailability, toxicities associated with a second ASCT. Herein, we report the first case of utilizing initially azacitidine and subsequently oral decitabine + cedazuridine (decitabine), in the context of relapsed PMF post-ASCT. Utilizing both hypomethylating agents provided disease control and improved donor/myeloid lineage chimerism levels, and the patient also remained transfusion independent, with preserved functional status and quality of life.

Patient age and donor HLA matching can stratify allogeneic hematopoietic cell transplantation patients into prognostic groups

BACKGROUND

Mixed results surround the accuracy of commonly used prognostic risk scores to predict overall survival (OS) and non-relapse mortality (NRM) in allogeneic hematopoietic stem cell transplant (allo-HCT) recipients. We hypothesize that a simple prognostic score performs better than conventional scoring systems.

PATIENTS AND METHODS

OS risk factors, HCT-CI, age-HCT-CI, and augmented-HCT-CI were studied in 299 patients who underwent allo-HCT for myeloid and lymphoid malignancies. A scoring system was developed based on results and validated in a different cohort of 455 patient.

RESULTS

2-year OS was 51% (95%CI 0.45-0.56). 2-year NRM was 34% (95%CI 0.29-0.39). HCT-CI and associated scores were grouped into 0-2 and ≥3. Age and HLA mismatch status were the only risk factors to affect OS in multivariate analysis (p = 0.02 and 0.05, respectively). HCT-CI and associated scores were not informative for OS prediction. The weighted scoring system assigned 0 to 2 points for age <50, 50 to 64, or ≥65, respectively, and 0 to 1 points for no HLA mismatch versus any mismatch (except HLA-DQ). Distinct 2-year OS [62%, 53%, and 38% (p = <0.001)] and NRM [24%, 34%, and 43% (p = 0.02)] groups were characterized. The scoring system was validated in a second independent cohort with similar results on OS and NRM (p <0.001).

CONCLUSIONS

A simple scoring system based on recipient's age and mismatch status accurately predicts OS and NRM in two distinct cohorts of allo-HCT patients. Its simplicity makes it a helpful tool to aid clinicians and patients in clinical decision making. This article is protected by copyright. All rights reserved.

The 17‐gene stemness score associates with relapse risk and long‐term outcomes following allogeneic haematopoietic cell transplantation in acute myeloid leukaemia

A 17‐gene stemness (LSC17) score determines risk in acute myeloid leukaemia patients treated with standard chemotherapy regimens. The present study further analysed the impact of the LSC17 score at diagnosis on outcomes following allogeneic haematopoietic cell transplantation (HCT). Out of 452 patients with available LSC17 score, 123 patients received allogeneic HCT. Transplant outcomes, including overall (OS), leukaemia‐free survival (LFS), relapse incidence (RI) and non‐relapse mortality (NRM), were compared according to the LSC17 scored group. The patients with a low LSC17 score had higher OS (56.2%) and LFS (54.4%) at 2 years compared to patients with high LSC17 score (47.2%, p = 0.0237 for OS and 46.0%, p = 0.0181 for LFS). The low LSC17 score group also had a lower relapse rate at 2 years (12.7%) compared to 25.3% in the high LSC17 score group (p = 0.017), but no difference in NRM (p = 0.674). Worse outcomes in the high LSC17 score group for OS, LFS and relapse were consistently observed across all stratified sub‐groups. The use of more intensive conditioning did not improve outcomes for either group. In contrast, chronic graft‐versus‐host‐disease was associated with more favourable outcomes in both groups. The 17‐gene stemness score is highly prognostic for survival and relapse risk following allogeneic HCT.

Relationship between certain HLA alleles and the risk of cytomegalovirus reactivation following allogeneic hematopoietic stem cell transplantation

INTRODUCTION

Evidence is emerging to support an association between certain HLA alleles and the risk of cytomegalovirus (CMV) reactivation following allogeneic HSCT (allo-HSCT). The primary aim of this study was to identify HLA alleles associated with resistance or susceptibility to CMV reactivation.

METHODS

We studied 586 adults who underwent allo-HSCT for high-risk hematological malignancies. High resolution HLA typing data was available for recipient and donor. HLA Class I and II alleles observed at a frequency of > 5% in our population, were included in the analysis. A CMV viremia level of more than 200 IU/ml on weekly monitoring was considered to be indicative of CMV reactivation.

RESULTS

The median follow-up time in surviving patients was 21 months (range 4-74 months). The cumulative incidence of CMV reactivation at 6 months in the entire cohort was 55% (95% CI 50.8%-59.2%). Mismatched donor, increasing recipient age, occurrence of AGVHD and recipient CMV seropositivity were associated with increased risk of CMV reactivation. HLA B*07:02 (HR 0.59, 95% CI 0.40-0.83) was associated with decreased risk of CMV reactivation. Patients who developed CMV reactivation had a lower incidence of relapse, higher transplant related mortality (TRM) and lower overall survival (OS) compared to those without CMV reactivation. There was an adverse correlation of OS and TRM with increasing numbers of CMV reactivations.

CONCLUSION

We observed that HLA B*07:02 was associated with decreased risk of CMV reactivation. CMV reactivation was associated with lower relapse post-transplant, but this did not translate into a survival benefit due to higher transplant related mortality. This article is protected by copyright. All rights reserved.

Comparison of Outcomes After Second Allogeneic Hematopoietic Cell Transplantation Versus Donor Lymphocyte Infusion in Allogeneic Hematopoietic Cell Transplant Patients

BACKGROUND

Allogeneic hematopoietic cell transplantation (HCT) is potentially curative for hematological disease however can be complicated by relapse or graft failure (GF), for which second-HCT and donor lymphocyte infusions (DLI) are performed. This study aimed to compare outcomes following the two interventions.

METHODS

We retrospectively investigated 89 patients with relapse or GF after first-HCT, 50 (56%) underwent second HCT and 39 (44%) received (DLI), from June 2011 to September 2020.

RESULTS

Median age at intervention was 55 years (19-72). Second-HCT was performed for relapse in 19 patients and for GF in 31 patients (primary GF in 11 and secondary in 20 patients), same donor was used in 25 (50%) patients. DLI was performed for relapse in 20 and for secondary GF in 19 patients. Median number of DLI administered was 2 (range 1-11). Univariate analysis demonstrated 2 year overall survival (OS) for second-HCT was superior when performed for relapse (65%) compared to GF (44%) (P = .03). For DLI patients, 2 year OS was 49% for GF and 45% for relapse patients (P = .49). For relapse as an indication, second-HCT demonstrated borderline superiority compared to DLI (P = .07). Multivariable analysis demonstrated for OS for the entire cohort demonstrated donor mismatch (HR 0.50, 95% CI 0.26%-0.94%, P = .03), KPS at time of intervention (HR 2.10, 95% CI 1.14%-3.85%, P = .02) and time from first-HCT to intervention (HR 0.51, 95% CI 0.28%-0.93%, P = .03) as significant variables.

CONCLUSION

Second-HCT may improve outcomes when performed for relapse post-transplant if patients achieve remission again, while DLI may be reserved for patients with active disease.

Allogeneic hematopoietic stem cell transplantation in patients with therapy-related hematologic malignancies developing after multiple myeloma

INTRODUCTION

Increasing survival of patients with multiple myeloma (MM) has resulted in an increased recognition of therapy-related hematological malignancies (t-MDS/AML, t-ALL, and t-CMML). There are limited data on the role of allogeneic hematopoietic stem cell transplantation (HCT) in this patient population.

PATIENTS AND METHODS

We retrospectively reviewed patients who underwent HCT for t-MDS/AML, t-ALL, and t-CMML developing after receiving treatment for MM at our center. Patients were analyzed for myeloma characteristics and therapy, time to diagnosis of therapy-related hematological neoplasms, clinical, laboratory characteristics, transplant details, relapse-free survival (RFS), and overall survival (OS).

RESULTS

Twenty patients underwent HCT for therapy-related hematological malignancies after MM (t-MDS/AML = 13, t-ALL = 6, t-CMML = 1). Median(range) age at time of transplant was 62.5 (49-73) years and 70% (n = 14) were male. The most common cytogenetic abnormality was complex/monosomal karyotype in 30% (n = 6) followed by monosomy/deletion of chromosome 5 or 7 in 15% (n = 3) of patients each. Donors were human leukocyte antigen matched (10/10 or 6/6) siblings in 30% (n = 6), unrelated in 60% (n = 12) and haploidentical in 10% (n = 2) patients. Estimated 2-year OS and RFS for the whole cohort were 53.1% and 47.2% respectively. There was a trend toward better survival in patients with t-ALL when compared to t-MDS/AML; however, the difference was not statistically significant. We did not find any pre-transplant or post-transplant factors that were predictive of survival outcomes after multivariate analysis.

CONCLUSIONS

Allogeneic HCT provides substantial long-term disease-free survival in a proportion of patients with MM-associated therapy-related hematological malignancies. Multicenter studies with more patients and longer follow-up may provide additional information about factors affecting outcomes.

Anti-thymocyte Globulin and Post-Transplant Cyclophosphamide do not abrogate the inferior outcome risk conferred by human leukocyte antigen-A and -B mismatched donors

In donor selection for allogeneic stem cell transplant, several factors are considered for potential impact on transplant outcome. Previous publications suggested single HLA-mismatched unrelated donors (MMUD) may be equivalent to 10/10 matched unrelated donors (MUDs). We retrospectively examined factors affecting outcome in a single-center study using ATG followed by post-transplant cyclophosphamide, termed ATG-PTCy, GvHD prophylaxis. Fifty-two patients who received grafts from MMUD and 188 patients transplanted from MUD between January 2015 and December 2019, at Princess Margaret Cancer Centre, Canada, were enrolled. All patients received reduced-intensity conditioning. Overall survival for 9/10 recipients at 2 years was significantly worse, 37.2% versus 68.5% for 10/10 MUDs, p < .001, as were NRM at 1 year 39.5% versus 11.7%, p < .001, and GRFS at 2 years 29.8% versus 58.8%, p < .001, respectively, potentially due to higher incidence of infections including CMV. By multivariable analysis, factors correlating with survival negatively were DRI, and MMUD, whereas for NRM MMUD and increasing age were unfavorable. For GRFS significant unfavorable factors included donor age ≤32 years, female donor to male recipient, DRI high-very high and MMUD. These data suggest that MMUD, primarily HLA-A and HLA-B MMUD, confer significantly inferior outcome despite use of ATG-PTCy. Further development of novel conditioning regimens and GvHD prophylaxis is needed to mitigate these risks.

Outcomes of patients diagnosed with chronic lymphocytic leukemia after allogeneic hematopoietic stem cell transplantation: Results from a tertiary care center

BACKGROUND

Allogeneic hematopoietic stem cell transplantation (allo-HCT) is currently the only curative treatment for patients with chronic lymphocytic leukemia (CLL).

METHODS

We analyzed the outcomes of 93 patients (median age: 52 years) who underwent allo-HCT at our center between 1989 and 2019.

RESULTS

After a median follow-up of 35 months, relapse was observed in 15.1% (n = 14) patients. The estimated 2-year non-relapse mortality, relapse-free survival, and overall survival (OS) were 38.1%, 54.2%, and 58.7%, respectively. The ECOG performance status ≥ 2 (hazard ratio [HR]: 4.1; p = .001) and use of total body irradiation (in a myeloablative conditioning regimen; HR: 2.64; p = .005) were predictive of poor OS after multivariable analysis. The occurrence of sinusoidal obstruction syndrome/veno-occlusive disease post-transplant was associated with poor survival (p = .001).

CONCLUSION

Although the use of kinase and bcl2 inhibitors may result in a decrease in the number and need of transplants, allo-HCT remains a viable option in selected patients with high-risk CLL and good performance status.

Anti-thymocyte globulin and post-transplant cyclophosphamide predisposes to inferior outcome when using cryopreserved stem cell grafts

During 2020, the concurrent novel COVID-19 pandemic lead to widespread cryopreservation of allogeneic hematopoietic cell transplant grafts based on National Marrow Donor Program and European Society of Blood and Marrow Transplantation recommendations, in order to secure grafts before the start of conditioning chemotherapy. We sought to examine the impact of this change in practice on patient outcomes. We analyzed the outcomes of 483 patients who received hematopoietic stem cell transplantation (HSCT) between August 2017 and August 2020, at Princess Margaret Cancer Centre, Canada, in the retrospective study, comparing the outcomes between those who received cryopreserved or fresh peripheral blood stem cell grafts. Overall compared with those who received fresh grafts (n = 348), patients who received cryopreserved grafts (n = 135) had reduced survival and GRFS, reduced incidence of chronic graft-versus-host disease (GvHD), delay in neutrophil engraftment, and higher graft failure (GF), with no significant difference in relapse incidence or acute GvHD. However, recipients of cryopreserved matched-related donor HSCT showed significantly worse OS, NRM, GRFS compared with fresh grafts. Multivariable analysis of the entire cohort showed significant impact of cryopreservation on OS, relapse, cGvHD, GF, and GRFS. We conclude that cryopreservation was associated with inferior outcomes post-HSCT, possibly due to the combination of ATG and post-transplant cyclophosphamide impacting differential tolerance to cryopreservation on components of the stem cell graft; further studies are warranted to elucidate mechanisms for this observation.

Lower dose of ATG combined with post-transplant cyclophosphamide for HLA matched RIC alloHCT is associated with effective control of GVHD and less viral infections

This study compares the outcomes before and after reducing the ATG dose from 4.5 to 2 mg/kg, in a combination of PTCy and CsA for GVHD prevention, in 250 patients treated with HLA matched RIC PB-alloHCT (70% received 4.5 mg/kg and 30% received 2 mg/kg). The incidences of grade II-IV and III-IV aGVHD at day +100, and moderate/severe cGVHD at 1-year were 12.6% vs. 20% (p = 0.431), 3.6% vs. 4.5% (p = 0.935), and 10.9% vs. 26.1% (p = 0.480), respectively. PTLD (9.1% vs. 1.3%, p = 0.026) and viral infections (30.3% vs. 12%; p = 0.001) were lower for those treated with 2 mg/kg of ATG. The reduction of the ATG dose resulted in a comparable OS (2-year: 64.7% vs. 64.7%), GRFS (2-year: 48.0% vs. 44.5%), RFS (2-year: 57.0% vs. 62.0%), and NRM (2-year: 17.8 vs. 14.9). The use of (2 mg/kg) ATG-PTCy-CsA for HLA matched RIC alloHCT results in lower viral infections, and incomparable GVHD preventive effect and survival rates.

Effect of pre-transplant JAK1/2 inhibitors and CD34 dose on transplant outcomes in myelofibrosis

Allogeneic hematopoeitic cell transplantation (allo-HCT) is the only curative treatment for myelofibrosis (MF). We evaluate the impact of various factors on survival outcomes post-transplant in MF. Data of 89 consecutive MF patients (primary 47%) who underwent allo-HCT between 2005 and 2018 was evaluated. Fifty-four percent patients had received JAK1/2 inhibitors (JAKi) pre-HCT. The median CD34 count was 7.1x10⁶ cells/kg. Graft failure was seen in 10% of the patients. Grade 3-4 acute GVHD (aGVHD) and moderate/severe chronic graft versus host disease (cGVHD) occurred in 24% and 40% patients, respectively. Two-year overall survival (OS) and relapse free survival (RFS) were 51% and 43%, respectively. Cumulative incidence of relapse (CIR) and non-relapse mortality (NRM) at 2 years were 11% and 46%, respectively. Higher CD34 cell dose (≤5 × 10⁶ cells/kg vs 5-9 or ≥9 × 10⁶  cells/kg) and lower pre-HCT ferritin (</=1000 ng/ml) were associated with better OS, RFS and lower NRM. Grade 3-4 aGVHD was associated with higher NRM. Use of pre-transplant JAKi was associated with lower incidence of grade 3-4 aGVHD. In summary, higher CD34 cell dose is associated with better allo-HCT outcomes in MF and pre-HCT JAKi use is associated with reduced risk of severe aGVHD. These two modifiable parameters should be considered during allo-HCT for MF.

Pretransplant bone marrow cellularity and blood count recovery are not associated with relapse or survival risk following allogeneic stem cell transplant for AML in CR

INTRODUCTION

Allogeneic hematopoietic cell transplantation (HCT) can be curative for acute myeloid leukemia (AML). Novel therapies may render patients' bone marrow hypocellularity and lead to prolonged post-therapy pancytopenia. Patients' bone marrow cellularity (BMC) at pretransplant assessment and post-treatment pancytopenia (classification CR-incomplete [CRi]) may manifest AML persistence.

METHODOLOGY

We retrospectively examined the impact of BMC and ELN response (ELNr) on a single-center cohort of 337 patients who underwent allogeneic HCT for AML in CR1.

RESULTS

Median follow-up was 33 months. Overall survival (OS) for the whole cohort was 55.8% at 2 years, while cumulative incidence of relapse (CIR) was 20.8%, and non-relapse mortality was 27.5%. OS and CIR were not significantly different between BMC groups; and neither was ELNr. ELNr CRi was associated with BMC aplastic and hypocellular marrow states (P < 2.6e-8). Multivariate analysis confirmed neither BMC nor attainment of ELNr CR vs CRi affected OS or relapse. Significant factors for survival included age at transplant, cytogenetic risk, development of acute Gr II-IV GvHD, and moderate-severe chronic GvHD, while cytogenetic risk and chronic GvHD affected relapse.

CONCLUSION

Neither ELNr status nor pretransplant BMC influenced relapse post-HCT or OS. Hypocellularity and CRi are not negative prognostic factors for post-HCT outcomes of AML.

Association of Factors Influencing Selection of Upfront Hematopoietic Cell Transplantation versus Nontransplantation Therapies in Myelofibrosis

Despite the curative potential of allogeneic hematopoietic cell transplantation (HCT) for myelofibrosis (MF), a significant number of patients with MF do not undergo HCT. Factors influencing treatment preferences in these patients have not been well studied. This study was conducted to identify patient-, disease-, and donor-related factors influencing the decision regarding HCT in patients with MF. A secondary objective was to compare survival between patients who elected upfront HCT and those who opted for nontransplantation therapy. We conducted a retrospective chart review amongst patients meeting criteria for transplant indication, evaluating clinical characteristics, treatment preferences, and outcomes. Of the 183 study eligible patients age <70 years, 129 (70%) developed an HCT indication. Age >60 years was significantly associated with higher rates of HLA-typing refusal (13 of 72 versus 1 of 44; P = .02). Caucasian ethnicity was significantly associated with an increased rate of identifying well-matched donors compared with non-Caucasian ethnicity (75% versus 48%; P = .02). Of the 69 patients with well-matched donors, 34 (49%) preferred to not pursue upfront HCT despite an indication for transplantation. Patient preference for nontransplantation therapies was the most common reason for declining HCT. We did not find any difference in survival between patients pursuing upfront HCT and those opting for nontransplantation therapies, although more patients in the HCT arm were in remission at the last follow-up. Patients of Caucasian ethnicity were significantly more likely than non-Caucasian patients to identify a well-matched donor. Despite availability of a well-matched donor, a significant proportion of MF patients with an indication for transplantation do not pursue HCT. Patient age, donor type, and patient preference play major roles in the selection of upfront HCT. Although a survival difference was not observed between upfront HCT versus non-transplant therapy, more patients in the HCT arm were in remission at the last follow-up.

Prognostic impact of the adverse molecular-genetic profile on long-term outcomes following allogeneic hematopoietic stem cell transplantation in acute myeloid leukemia

The impact of adverse risk genetic profiles on outcomes in acute myeloid leukemia (AML) patients following allogeneic hematopoietic stem cell transplantation (HCT) has not been fully elucidated. Accordingly, we have profiled somatic mutations at diagnosis using next-generation sequencing (NGS) in 178 AML patients who received allogeneic HCT. NGS revealed 598 somatic mutations in 165/178 patients (92.7%). Frequently mutated genes include DNMT3A, TET2, NPM1, RUNX1, IDH2, and FLT3. Commonly detected cytogenetic profiles include normal karyotype, trisomy 8, monosomal karyotype (MK), deletion 5, complex karyotype (CK), and monosomy 7. In univariate analyses, TP53 mutation, MK, CK, and monosomy 7 were associated with decreased overall survival (OS), relapse-free survival (RFS), and a higher relapse incidence (RI). We defined adverse molecular-genetic profile as harboring at least one of the molecular/genetic abnormalities of TP53 mutation, MK, CK, monosomy 7, and deletion 5. The patients harboring adverse molecular-genetic profile (n = 30) showed a lower 2-year OS (24.9% vs. 57.9%; p = 0.003), RFS (23.7% vs. 57.9%; p = 0.002), and higher RI (47.2% and 17.2%; p = 0.001) after HCT when compared to patients without those lesions. Multivariate analysis confirmed adverse molecular-genetic profile as an independent prognostic factor, associated with decreased OS (HR 2.19), RFS (HR 2.23), and higher RI (HR 2.94).

Predictors of outcomes of therapy-related acute myeloid leukemia after allogeneic hematopoietic stem cell transplantation

BACKGROUND/OBJECTIVE

Existing literature on allogeneic hematopoietic stem cell transplantation (allo-HSCT) in therapy-related acute myeloid leukemia (t-AML) is confounded by the inclusion of patients with secondary AML and t-MDS. We aim to report our 20-year experience of HSCT in t-AML.

METHODS

We retrospectively reviewed patients with t-AML who underwent HSCT. Patients were analyzed for prior malignancy, therapy, time to diagnosis of t-AML, transplant details, relapse-free survival (RFS), overall survival (OS), and predictors of outcomes.

RESULTS

In total, 68 patients (59.9% female; median age, 56.5 years) underwent HSCT. Acute and chronic graft-versus-host disease (GVHD) occurred in 39 (57.4%) and 23 (33.8%) patients, respectively. Cumulative incidence of relapse, nonrelapse mortality, RFS, and OS at 2 years were 17.9%, 34.5%, 47.6%, and 49.3%, respectively. Significant predictors of reduced OS were presence of 11q23 rearrangement (hazard ratio [HR], 3.24), using induction regimens other than FLAG-Ida or 7 + 3 (HR, 3.65), haploidentical donors (HR, 3.48), Eastern Cooperative Oncology Group performance status 2 or higher (HR, 5.83), and using cyclosporine A-methotrexate as GVHD prophylaxis (HR, 2.41). A significant decrement in survival was seen with an increasing number of any of these prognostic factors.

CONCLUSION

Outcomes of t-AML are satisfactory after allo-HSCT. Patients with t-AML with good-risk karyotypes, good performance status, having HLA-matched donors, and receiving intensive induction regimens have better outcomes after HSCT.

Comparison of the Prognostic Ability of the HCT-CI, the Modified EBMT, and the EBMT-ADT Pre-transplant Risk Scores for Acute Leukemia

BACKGROUND

Allogeneic hematopoietic cell transplantation (HCT) outcomes may be predicted by published risk scores; however, the ideal system has not been identified for acute leukemias.

PATIENTS AND METHODS

We retrospectively examined the Hematopoietic Cell Transplantation-Comorbidity Index (HCT-CI), modified European Group for Blood and Marrow Transplantation (mEBMT), EBMT-Alternating Decision Tree (ADT), and others on 231 patients with acute leukemia.

RESULTS

Acute myeloid leukemia was diagnosed in 200 patients, and acute lymphocytic leukemia was diagnosed in 31 patients. For HCT-CI, patients were grouped as 0 to 1, 2 to 3, and > 3. For mEBMT, patients were grouped as 0 to 2, 3, and > 3. For EBMT-ADT, the 100-day mortality was calculated and grouped as ≤ 4.1%, 4.1% to 11.5%, and > 11.5%. Higher HCI-CI demonstrated inferior overall survival (P = .04; c-statistic, 0.57), whereas mEBMT and EBMT-ADT did not stratify well. A new weighted score was developed that assigned 1 point for age ≥ 60 years, acute lymphocytic leukemia diagnosis, mismatch unrelated or haploidentical donor, cardiovascular comorbidity, and pre-transplant diabetes, whereas arrhythmia received 2 points. The new weighted score assigned 0 points to 88 (38%), 1 to 2 points to 121 (52%) and ≥ 3 points to 22 (10%) patients, and demonstrated improved prognostic capability compared with the other scores (P = .0001; c-statistic, 0.61).

CONCLUSIONS

The HCT-CI stratifies patients with leukemia for overall survival but is inferior to our single-center score, which is influenced by cardiac comorbidity and arrhythmia. Differences in pre-transplant risk scores may be related to different transplant practices.

Subcutaneous immunoglobulin in allogeneic hematopoietic cell transplant patients: A prospective study of feasibility, safety, and healthcare resource use

BACKGROUND

We evaluated feasibility, safety, and total resource use of subcutaneous immunoglobulin (SCIG) in a pilot study of patients who underwent allogeneic hematopoietic cell transplant (HCT) over a 6-month period.

METHODS

A total of 20 eligible patients were treated with SCIG at 0.1 g/kg/week for up to 6 months. Patients were matched to 20 concurrent intravenous immunoglobulin (IVIG) controls. Clinical outcomes measured included adverse reactions, healthcare resource use, patient satisfaction, and quality of life (QOL). (ClinicalTrials.gov Identifier: NCT03401268.) RESULTS: Groups were comparable in terms of age, weight, sex, transplant indication, donor type, and conditioning intensity. All 20 IVIG patients completed 6 consecutive months of therapy compared with 13/20 (65%) SCIG patients. There were no adverse reactions in IVIG patients, compared with six (30%) SCIG patients. All adverse reactions in SCIG patients were grade I, transient, and required no medical intervention. Median overall cost per patient was lower with SCIG than with IVIG ($9,756 vs. $13,780, p = .046). Among patients who completed 6 months of SCIG, median preference and satisfaction scores were 100%. Over the 6-month period, QOL scores remained stable in SCIG patients.

CONCLUSIONS

In a subgroup of patients, SCIG was associated with high patient satisfaction and a reduction in total healthcare costs compared with IVIG in a cohort of HCT patients.

Experience Using Anti-Thymocyte Globulin With Post-Transplantation Cyclophosphamide for Graft-Versus-Host Disease Prophylaxis in Peripheral Blood Haploidentical Stem Cell Transplantation

Haploidentical hematopoietic cell transplantation (HaploHCT) is an alternative treatment option for patients without a suitable 10/10 HLA matched donor. We share an updated experience at our center of using in vivo dual T-cell depletion with anti-thymocyte globulin (ATG) and post-transplantation cyclophosphamide (PTCy) in peripheral blood haploHCT and report the impact of reducing the dose of ATG from 4.5 mg/kg to 2 mg/kg on post-transplantation complications and outcomes. Ninety-five consecutive adults underwent haploHCT at our center between August 2016 and February 2020, all of whom were included in the study. Nine (9.5%) patients received myeloablative conditioning, and 86 (90.5%) patients underwent reduced-intensity haploHCT. All patients received thymoglobulin, PTCy and cyclosporine (CsA) for graft-versus-host disease (GVHD) prophylaxis: Sixty (63.2%) patients received 4.5 mg/kg, and 35 (36.8%) patients received 2 mg/kg of ATG. Clinical information was collected retrospectively and updated in June 2020. The median age was 57 (18-73), and acute myeloid leukemia was the most prevalent diagnosis (58.9%). The day 100 cumulative incidence of grade II-IV and grade III-IV aGVHD, and 1-year moderate/severe cGVHD were 22.3%, 11.1%, and 20.2%, respectively. Those patients who received 2 mg/kg of ATG had higher incidence of grade III-IV aGVHD (23.9% vs 3.5%, P = .006) and comparable moderate/severe cGVHD (1-year 20.6% vs 19.8%, P = .824) than those patients who received 4.5 mg/kg. Overall, the 18-month overall survival (OS), relapse-free survival (RFS), and non-relapse mortality (NRM) were 43.8%, 38.4%, and 40.2%, respectively. The reduction of the ATG dose did not have a significant impact in OS (hazard ratio [HR] 1.06, P = .847), RFS (HR 0.984, P = .955), and in NRM (HR 1.38; P = .348). The reduction of the ATG resulted in a negative impact on aGVHD without conferring any benefit in OS, RFS, and NRM. Consequently, the ATG dose used at our institution in combination with PTCy and CsA for haploHCT continues to be 4.5 mg/kg.

Fresh vs. frozen allogeneic peripheral blood stem cell grafts: A successful timely option

Cryopreservation of grafts has been established in autologous and cord blood transplantation, yet there is little experience regarding the effect of cryopreservation with sibling and unrelated grafts. We evaluated the effect of cryopreservation of grafts on allogeneic transplant outcomes using related, unrelated and haploidentical donors, including 958 patients, age 18-74 years (median 55) and using PBSC for various hematologic malignancies. Fresh grafts were received by 648 (68%) patients, 310 (32%) received cryopreserved. There was no difference between fresh vs cryopreserved grafts for neutrophil engraftment (P = .09), platelet engraftment (P = .11), graft failure (5.6% vs 6.8%, P = .46) and grade II-IV acute graft-vs-host disease (GVHD) (P = .71), moderate/severe chronic GVHD was observed in 176 (27%) vs 123 (40%) patients, respectively (P < .001). Multivariable analysis demonstrated no difference between fresh vs cryopreserved for OS (P = .39) and CIR (P = .08) while fresh grafts demonstrated borderline increased NRM (HR 1.27, 95% CI 1.02-1.59, P = .04). Of note, for patients with no or mild chronic GVHD, CIR was less for fresh compared to cryopreserved (HR = 0.67 for fresh, 95% CI 0.48-0.92, P = .01). We conclude there were no differences in engraftment and survival between fresh and cryopreserved grafts for allogeneic HCT, thus establishing cryopreservation to be a safe option for allogeneic HCT.

Refined hepatic grading system in chronic graft-versus-host disease improves prognostic risk stratification of long-term outcomes

OBJECTIVES

Hepatic grading systems for categorizing severity in chronic graft-versus-host disease (cGvHD) were determined arbitrarily, leading us to initiate the present study to provide objective evidence for the determination of optimal cutoff values and devise a hepatic grading system to predict prognosis.

METHODS

Of 842 patients who received allogeneic hematopoietic stem transplant (HCT), 336 patients diagnosed with cGvHD were evaluated for overall survival (OS) and non-relapse mortality (NRM) after cGVHD development. Multiple statistical parameters were evaluated to define optimal cutoff values of liver profile, including negative predictive value (NPV), positive predictive value (PPV), accuracy, and p-values as measures of risk stratification power.

RESULTS

We found that alkaline phosphatase (ALP) ≥ 146 IU/L (NPV: 83.4%; PPV: 32.8%; accuracy: 52.7%) and bilirubin ≥ 14 µmol/L (NPV: 81.8%; PPV: 39.4%; accuracy 68.1%) significantly correlated with OS. We developed a refined hepatic cGvHD grading score (RHS), stratifying patients into a low-RHS group with RHS score 0, OS at 3 years (n = 162) to 80.5%, compared to high-RHS group with score 1-2 (n = 172) 62.7%. Regarding NRM, score 0 segregated NRM at 3 years to 11.9%, compared with score 1-2 19.6%, P = .1.

CONCLUSIONS

Refined hepatic score is promising for stratifying patients with cGVHD and liver involvement according to long-term outcomes.

Comorbidity profile of adult survivors at 20 years following allogeneic hematopoietic cell transplantation

Numerous chronic medical conditions and complications can arise following allogeneic hematopoietic cell transplantation (HCT) that may have a negative impact on survival and quality of life.

OBJECTIVE

The purpose of the present study was to review the comorbidities of a single-center cohort of allogeneic HCT recipients that survived 20 years postallogeneic transplantation.

METHODS

We retrospectively investigated 172 patients that underwent allogeneic HCT at the Princess Margaret Cancer Centre between 1979 and 1998 and who survived at least 20 years post-HCT.

RESULTS

The most frequent individual comorbidities documented were dyslipidemia (29%), hypertension (31%), osteoporosis (15%), hypothyroidism (15%), and depression/anxiety (13%). Follow-up data following the 20-year mark were available for 135 patients, overall survival (OS) of that group at 5 and 10 years was 94% and 90%, respectively. When grouped by the number of concurrent comorbidities, there was a significant difference in OS between the groups with 0-1, 2-3, and ≥4 comorbidities (P = .01).

CONCLUSIONS

Evidently, long-term allogeneic HCT recipients may develop a number of comorbidities that negatively influence survival even past the 20-year post-transplant mark. These findings warrant the continuous long-term medical follow-up of allogeneic transplant patients, regardless of age or time that has lapsed post-HCT.

Prolactin, a potential biomarker for chronic GVHD activity

INTRODUCTION

The polypeptide prolactin (PRL) is a peptide hormone and a cytokine mostly secreted from the anterior pituitary gland. PRL is also synthesized in extra pituitary tissues including thymocytes and T lymphocytes. Considering the need for chronic GVHD (cGVHD) biomarkers, we explored the relationship between hyperprolactinemia and active cGVHD in a cohort of long-term post-alloHCT survivors.

METHODS

Three-hundred sixteen adults underwent alloHCT between 2010 and 2016, survived more than 1 year and were included. All patients underwent a regular annual assessment that includes a hormone profile with serum PRL levels.

RESULTS

Overall, 236 (74.7%) patients had cGVHD, and in 199 (63%), the grade was moderate or severe. Sixty-five (21%) recipients had active cGVHD at the time of the annual evaluation, and hyperprolactinemia was documented in 63 (19.9%) patients. Hyperprolactinemia correlated with cGVHD activity (Odds Ratio 6.9 (95% CI; 3.6-13.1); P < .001) in the multivariate analysis. In conclusion, patients with hyperprolactinemia were 6.4 times more likely to have active cGVHD in comparison with those patients with normal levels of PRL (P < .001).

CONCLUSION

Prolactin may serve as a biomarker for cGVHD activity. Further studies are required to confirm these findings, and to explore if hyperprolactinemia has an impact on cGVHD severity and prognosis.