Incidence, Predictors, and Outcomes of Veno-Occlusive Disease/Sinusoidal Obstruction Syndrome after Reduced-Intensity Allogeneic Hematopoietic Cell Transplantation.

fludarabine with intravenous busulfan at doses of 3.2 mg/kg (Flu/Bu1) or 6.4 mg/kg (Flu/Bu2). Hepatic veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) is a serious complication of hematopoietic stem cell transplantation (HCT) that is felt to be triggered, at least in part, by damage to the liver sinusoidal endothelium from cytotoxic conditioning regimens. Accordingly, the incidence of VOD/SOS after reduced-intensity conditioning (RIC) HCT is low compared with myeloablative transplantation, and the natural history, risk factors, and outcomes of VOD/SOS after RIC have not been well characterized. We retrospectively reviewed 1583 consecutive patients receiving RIC HCT at the Dana-Farber Cancer Institute between 2007 and 2017 and ascertained 26 cases of VOD/SOS. The median day of VOD/SOS onset was 26 days (range, 5 to 48) and the cumulative incidence at day 50 was 1.6% (95% confidence interval [CI], 1.1% to 2.4%). Day 100 nonrelapse mortality rate was 23% in the VOD/SOS cohort compared with 6.4% in patients without VOD/SOS (P = .006). Cumulative incidence of VOD/SOS at day 50 was 3.1% after RIC regimen with Flu/Bu2 ± ATG (fludarabine with two doses of busulfan, total dose 6.4 mg/kg, with or without anti-thymocyte globulin), compared with 0.15% after Flu/Bu1 ± ATG (fludarabine with single busulfan dose 3.2 mg/kg, with or without anti-thymocyte globulin) (P = .0002); the incidence rate was 2.1% after RIC HCT with sirolimus-containing graft-versus-host disease prophylaxis, compared with 0.8% for RIC without sirolimus (P = .06). Significant risk factors identified in multivariable analysis for the development of VOD/SOS were sirolimus use (hazard ratio [HR], 5.1; 95% CI, 1.8 to 14.2; P = .002) and RIC regimen with Flu/Bu2 ± ATG (HR, 34; 95% CI, 4.5 to 252; P < .001) or other (HR, 32; 95% CI, 3.9 to 257; P = .001) compared with Flu/Bu1 ± ATG. Rising serum tacrolimus or sirolimus levels, new acute kidney injury, and increasing platelet transfusion requirements were significant early predictors of onset in the week preceding prior VOD/SOS diagnosis. When compared with a previously published cohort of 76 patients with VOD/SOS who developed VOD/SOS after myeloablative HCT in the same time period, VOD/SOS after RIC occurred later and was associated with a lower peak bilirubin level and better overall survival. The variability in presenting features for RIC VOD/SOS highlights the importance of maintaining a high index of suspicion for this entity in RIC HCT.

Early Clinical Predictors of Hepatic Veno-Occlusive Disease/Sinusoidal Obstruction Syndrome after Myeloablative Stem Cell Transplantation.

Hepatic veno-occlusive disease (VOD), or sinusoidal obstruction syndrome (SOS), is a serious complication of hematopoietic stem cell transplantation (HSCT) with mortality in its severe form exceeding 80%. Although the incidence of VOD/SOS has fallen with contemporary transplantation practices, the increasing use of inotuzumab, the return of gemtuzumab, and the popularity of pharmacokinetic-guided high-dose busulfan may impact incidence. Early intervention with defibrotide improves survival, but prompt diagnosis can be difficult. We aimed to identify clinical parameters that could aid in early detection of VOD/SOS in a large, retrospective, cohort study. Of the 1823 adult patients who underwent myeloablative HSCT between 1996 and 2015 in our center, 205 (11%) developed VOD/SOS, with a median onset of day +14. We compared parameters in the 7 days preceding VOD/SOS onset for cases to 447 randomly selected control subjects in an analogous time frame to determine those with predictive value. Between 7 days before and the day of diagnosis, VOD/SOS patients had higher serum creatinine levels and were more likely to develop acute kidney injury (61% versus 33%, P < .0001), more commonly experienced refractoriness to platelet transfusion (48% versus 24%, P < .0001), and had higher trough serum tacrolimus levels (7 days before VOD/SOS onset: median 8.8 versus 7.3, P = .0002; day of onset: median 9.3 versus 7.2, P < .0001) compared with control subjects. Acute renal dysfunction, platelet refractoriness, and elevated or abnormal tacrolimus levels are dynamic clinical markers that should alert clinicians to the development of VOD/SOS before the presence of classical diagnostic criteria. Using these clinical features to recognize VOD/SOS earlier in its clinical course could promote earlier treatment and lead to improved outcomes of this potentially serious complication.

A Comparison of the Myeloablative Conditioning Regimen Fludarabine/Busulfan with Cyclophosphamide/Total Body Irradiation, for Allogeneic Stem Cell Transplantation in the Modern Era: A Cohort Analysis.

With improvement in transplantation practices in the modern era, nonrelapse mortality (NRM) following allogeneic hematopoietic stem cell transplantation (HSCT) has improved, while disease relapse rates have remained unchanged. Survival outcomes are therefore driven by NRM in the modern era. Myeloablative conditioning (MAC) regimens are used to maximize disease control and facilitate engraftment; however, their use is often limited by toxicity. The commonly used MAC regimens incorporate either chemotherapy plus total body irradiation (TBI) or combination chemotherapy. Furthermore, reduced-toxicity myeloablative (RTM) regimens, such as fludarabine/busulfan (FluBu), have emerged as alternatives to traditional MAC and their impact on outcomes in the current era have not been fully investigated. In this study, we compare outcomes following HSCT, using the chemotherapy only RTM MAC regimens FluBu with the chemoradiotherapy regimen cyclophosphamide/TBI (CyTBI), for patients with hematologic malignancies who underwent MAC HSCT at the Dana-Farber Cancer Institute. We hypothesized that the chemotherapy-only regimen would fare better, primarily due to improved NRM. A retrospective cohort analysis was performed on 387 patients with myeloid or lymphoid hematologic malignancies who underwent HLA-matched related (8/8), matched unrelated (8/8), or single-antigen mismatched unrelated (7/8) HSCT following myeloablative conditioning. Patients received FluBu (n = 158) or CyTBI (n = 229). The primary outcome was overall survival (OS) and all other outcomes were regarded as secondary. A subset analysis was performed for patients <55 years of age and for acute myelogenous leukemia/myelodysplastic syndrome patients of age <55 years. For the whole cohort, 3-year OS was similar for FluBu compared with CyTBI in unadjusted analysis. However, in multivariable analysis, FluBu resulted in superior OS compared with CyTBI (3-year adjusted estimate: 65% versus 55%, respectively; HR for death, .62; 95% CI, .40 to .97; P = .036). While relapse rates were similar between the 2 regimens, NRM and acute graft-versus-host disease (GVHD) (grade II to IV) were significantly worse with CyTBI compared with FluBu. Rates of chronic GVHD were similar between 2 regimens. These results were consistent in a subset of patients <55 years of age and in acute myelogenous leukemia/myelodysplastic syndrome patients below 55 years of age. The RTM chemotherapy-only regimen FluBu appears to be as effective and more tolerable than the chemoradiotherapy regimen CyTBI, leading to better OS driven by better NRM. The improvement in NRM was attributable chiefly to lower rates of grade II to IV acute GVHD. Relapse rates were not increased with FluBu. In the absence of randomized data, FluBu appears to be the optimal regimen for myeloablative HSCT in patients of all age groups.

Phase II trial of natalizumab with corticosteroids as initial treatment of gastrointestinal acute graft-versus-host disease.

The α4ß7 integrin is upregulated on naive and memory T cell subsets in patients who subsequently develop gastrointestinal (GI) acute GVHD. Natalizumab (Tysabri®, Biogen Inc.) acts against the α4 subunit that mediates homing of lymphocytes to the GI tract. We initiated a phase II study of natalizumab with corticosteroids for initial treatment of acute GI GVHD. In total, 300 mg IV of natalizumab was given, with steroids initiated up to 3 days prior. Twenty-one subjects were treated, median age was 63 years (range 38-74), and 15 (71%) were male. Eighteen (86%) underwent RIC, 15 (71%) received MUD, and all received PBSCs. Overall GVHD at enrollment was grade II in 4 and grade III in 17. The primary endpoint, day 56 GVHD-free survival rate, was attained in 33.3%. The overall response rate at day 28 and 56 was 57% and 52%, respectively. Six of eight CRs were durable for 1 year. Five experienced toxicity possibly related to natalizumab and ten had infections before day 100. 2-year OS was 43% (95% CI 22-62%) and 2-year NRM was 52% (95% CI 29-71%). Natalizumab with corticosteroids as initial treatment of acute GI GVHD is safe, effective, and durable.