A Retrospective Review of the Outcome after Second or Subsequent Allogeneic Transplantation

Geriatric nutritional risk index as a useful prognostic factor in second allogeneic hematopoietic stem cell transplantation

Second allogeneic hematopoietic stem cell transplantation (allo-HSCT) has a low survival outcome and a high non-relapse mortality (NRM) rate which is a major obstacle to this treatment. We hypothesized that the status of malnourishment after first allo-HSCT as represented by the geriatric nutritional risk index (GNRI) could be used as a prognostic factor to determine the outcomes of second allo-HSCT. A total of 108 patients with a median age of 42 (range, 17-69) years, who received second allo-HSCT for disease recurrence after first allo-HSCT from our institution, were included in this study. Low GNRI had a significant impact on NRM at 2 years after second allo-HSCT: 56.9% in patients with GNRI ≤ 92 compared with 27.5% in patients with GNRI > 92 (P = 0.002). In multivariate analysis, GNRI of ≤ 92 was the only significant factor for NRM (hazard ratio [HR] 2.29, 95% confidence interval [CI] 1.15-4.56, P = 0.018). High-risk disease status at second allo-HSCT (HR 2.74, 95% CI 1.46-5.14, P = 0.002) and GNRI of ≤ 92 (HR 1.70, 95% CI 1.02-2.82, P = 0.042) were identified as significant factors for overall survival (OS). A score of 1 was assigned to each factor, and the OS rate at 2 years after second allo-HSCT decreased according to the score: 53.0% in patients with score 0, 32.3% with score 1, and 2.5% with score 2 (P < 0.001). In conclusion, GNRI could be a useful predictor for the outcomes of second allo-HSCT. A prospective study in other cohorts is warranted to validate the findings of our study.

Donor selection for a second allogeneic stem cell transplantation in AML patients relapsing after a first transplant: a study of the Acute Leukemia Working Party of EBMT

Second allogeneic stem-cell transplantation (SCT2) is a therapeutic option for patients with AML relapsing after a first transplant. Prior studies have shown similar results after SCT2 from the same or different donor; however, there are limited data on second non-T-depleted haplo-identical transplant in this setting. We retrospectively analyzed SCT2 outcomes in 556 patients, median age 46 years, relapsing after first transplant given in CR1. Patients were divided into three groups based on SCT2 donor (donor2): same donor (n = 163, sib/sib-112, UD/UD-51), different matched donor (n = 305, sib/different sib-44, sib/UD-93, UD/different UD-168), or haplo-donor (n = 88, sib/haplo-45, UD/haplo-43). Two-year leukemia-free survival (LFS) rate after SCT2 was 23.5%, 23.7%, and 21.8%, respectively (P = 0.30). Multivariate analysis showed no effect of donor2 type on relapse: hazard ratio (HR) 0.89 (P = 0.57) and 1.11 (P = 0.68) for different donor and haplo-donor compared to same donor, respectively. However, donor2 did predict for non-relapse mortality (NRM) after SCT2: HR 1.21 (P = 0.50) and 2.08 (P = 0.03), respectively, and for LFS: HR 1.00 (P = 0.97) and 1.43 (P = 0.07), respectively. In conclusion, SCT2 with the same or different matched donor is associated with similar outcomes in patients with relapsed AML. Non-T-depleted haplo-identical transplant may be associated with higher NRM, similar relapse rate and with no better results in this setting.

Immunosuppressive Total Nodal Irradiation-Based Reconditioning Regimens After Graft Rejection or Graft Failure in Pediatric Patients Treated With Myeloablative Allogeneic Hematopoietic Cell Transplantation

PURPOSE

This retrospective analysis aimed to address the efficacy of total nodal irradiation (TNI)-based reconditioning regimens in pediatric patients with graft failure/rejection after allogeneic hematopoietic cell transplantation.

METHODS AND MATERIALS

Thirty-three pediatric patients with malignant (n = 25) and nonmalignant diseases (n = 8) were treated with a TNI-based reconditioning regimen. All patients received a 7-Gy single dose combined with anti-T lymphocyte antibody OKT3 (n = 16), anti-thymocyte globulin (n = 24), fludarabine (n = 31), and/or thiotepa (n = 28), followed by an infusion of peripheral blood stem cells (n = 31) or bone marrow transplant (n = 2). Twenty-eight of 33 patients had haploidentical family donors.

RESULTS

After a median of 11 days, engraftment was seen in 32 of 33 children. Two children died 34 days after retransplantation because of either disease relapse or treatment-related multiple organ failure. Severe acute toxicity was reported in only 1 child (systemic inflammatory response syndrome-like reaction; recovery after cortisone treatment). The average follow-up was 60.2 months (range, 1.1-162.5 months). Event-free and overall survival rates at 2/5 years follow-up were 62.0%/58.6% and 65.1%/61.7%, respectively. Despite sustained engraftment, 12 patients died from disease relapse (n = 3), Moschkowitz syndrome (n = 1), or multiple organ failure (n = 8). Follow-up data were available for 18 of 21 survivors, with a median follow-up of 92.8 months (range, 3.6-162.5 months). Hypothyroidism was present in 78.6% of patients, and sex/growth hormonal insufficiencies were reported for 37.5%. Mean forced expiratory volume in 1 second after TNI was 84%; mean vital capacity was 79%. Severe growth failure (<3rd percentile) occurred in 28.6% (height) and 35.7% (weight) of patients. No secondary malignancies were reported.

CONCLUSIONS

In the high-risk group of patients with graft failure/rejection after allogeneic hematopoietic cell transplantation, the TNI-based reconditioning regimen seems to allow sustained engraftment combined with a favorable toxicity profile, leading to long-term event-free and overall survival. Late toxicity after a median follow-up of over 7.5 years includes growth failure, manageable hormonal deficiencies, and a low risk of decrease of lung function.

[Second allogeneic hematopoietic stem cell transplant: Guidelines from the francophone Society of bone marrow transplantation and cellular therapy (SFGM-TC)]

Disease recurrence and graft dysfunction after allogeneic hematopoietic stem cell transplantation (allo-HSCT) currently remain among the major causes of treatment failure in malignant and non-malignant hematological diseases. A second allo-HSCT is a valuable therapeutic option to salvage those situations. During the 8th annual harmonization workshops of the french Society of bone marrow transplantation and cellular therapy (SFGM-TC), a designated working group reviewed the literature in order to elaborate unified guidelines on feasibility, indications, donor choice and conditioning in the case of a second allo-HSCT. In case of relapse, a second allo-HSCT with reduced intensity or non-myeloablative conditioning is a reasonable option, particularly in patients with a good performance status (Karnofsky/Lansky>80%), low co-morbidity score (EBMT score≤3), a longer remission duration after the first allo-HSCT (>6 months), and who present low disease burden at the time of second allo-HSCT. Matched related donors tend to be associated with better outcomes. In the presence of graft dysfunction (primary and secondary graft rejection), an immunoablative conditioning regimen is recommended. A donor change remains a valid option, especially in the absence of graft-versus-host disease after the first allo-HSCT.

Outcome following second allogeneic hematopoietic cell transplantation: A single-center experience

OBJECTIVE

Second allogeneic hematopoietic cell transplantation (HCT) may be indicated following relapse or graft failure following first HCT. Our retrospective single-center study sought to investigate parameters that influence post-second allogeneic HCT survival.

METHOD

We investigated 92 patients who underwent second allogeneic HCT between 1980 and 2016 for relapse or graft failure following first HCT. Median age at second HCT was 41 years (range 16-68), performed for relapse in 59 patients (64%) and for graft failure in 33 patients (36%).

RESULTS

On univariate analysis, 3-year OS of the entire cohort was 35% (95% CI=25-45). Eastern Cooperative Oncology Group (ECOG) score (3-year OS 48% for ECOG 0-1, 18% for ECOG 2-3, P=.0006), second HCT indication (3-year OS 43% for relapse, 20% for graft failure, P=.02), time from first HCT to relapse/graft failure (3-year OS for <12months 21%, for ≥12months 46%, P=.009), and conditioning intensity (3-year OS for MA 42% vs other regimens 23%, P=.08) significantly influenced OS. Multivariable analysis confirmed ECOG score (HR=2.15 for ECOG 2-3, 95% CI=1.32-3.51, P=.002) and second HCT indication (HR=1.67 for graft failure, 95% CI=1.02-2.75, P=.04) to independently influence survival.

CONCLUSION

Second HCT may offer long-term survival particularly to patients with good performance status who relapse post-first HCT.

The role of second transplants for leukemia

Management of relapsed leukemia following allogeneic transplantation is challenging. Intensive chemotherapy, donor lymphocyte infusions (DLI), or second transplantation have some value, but most reported series describe only a limited number of patients surviving beyond 2 or 3 years following relapse. Additionally, understandable selection-bias of reports describing the outcomes of intensive management approaches for relapsed leukemia confound generalizability to a broader population. However numerous reports suggest that second allogeneic transplantation for relapsed leukemia following an initial transplant may produce extended disease control and survival for patients with favorable performance status, remission at the time of second transplant, and most importantly a long interval between initial transplant and relapse. Reduced intensity conditioning for second allografts may be preferable and little data exists to suggest that a new donor will improve disease control by inducing a stronger graft-versus-leukemia effect. Improved measures to prevent the first relapse, however, may protect more patients and produce a greater fraction enjoying extended leukemia-free survival.

Treatment of graft failure with TNI-based reconditioning and haploidentical stem cells in paediatric patients

Graft failure is a life‐threatening complication after allogeneic haematopoietic stem cell transplantation (HSCT). We report a cohort of 19 consecutive patients (median age: 8·5 years) with acute leukaemias (n = 14) and non‐malignant diseases (n = 5) who experienced graft failure after previous HSCT from matched (n = 3) or haploidentical donors (n = 16) between 2003 and 2012. After total nodal irradiation (TNI)‐based reconditioning combined with fludarabine, thiotepa and anti‐T cell serotherapy, all patients received T cell‐depleted peripheral blood stem cell grafts from a second, haploidentical donor. Median time between graft failure and retransplantation was 14 d (range 7–40). Sustained engraftment (median: 10 d, range 9–32) and complete donor chimerism was observed in all evaluable patients. 5 patients additionally received donor lymphocyte infusions. Graft‐versus‐host disease (GvHD) grade II and III occurred in 1 patient each (22%); no GvHD grade IV was observed. 2 patients had transient chronic GvHD. The regimen was well tolerated with transient interstitial pneumonitis in one patient. Treatment‐related mortality after one year was 11%. Event‐free survival and overall survival 3 years after retransplantation were 63% and 68%. Thus, a TNI‐based reconditioning regimen followed by transplantation of haploidentical stem cells is an option to rescue patients with graft failure within a short time span and with low toxicity.

Factors associated with improved outcomes after second allogeneic hematopoietic cell transplantation for relapsed pediatric leukemia

A second allogeneic (allo) hematopoietic cell transplant (HCT) is an important therapeutic consideration for patients relapsing after their first. We conducted a retrospective review of 41 pediatric patients with leukemia that underwent a second allo-HCT at our institution. Overall, 53.7 and 43.9 % of patients were alive and disease-free at 1 and 5 years, respectively, after the second allo-HCT. The factors affecting outcome by both univariate and multivariate analysis were interval between transplants and the use of a myeloablative conditioning (MAC) regimen prior to second transplant. Outcomes were inferior in patients who received their second transplant <6 months from their first HCT when compared to patients in whom the interval between HCTs was 6-12 or more than 12 months. Interval between HCTs was also significant when each type of leukemia (acute lymphoblastic leukemia (ALL) n = 21, acute myelogenous leukemia (AML) n = 11, and chronic myelogenous leukemia (CML) n = 7) was analyzed separately. In univariate analysis, use of the same donor and use of a matched sibling donor resulted in significant improved outcome. There was not a significant association between disease-free survival (DFS) and age, remission status, use of total body irradiation (TBI) before second HCT, or type of leukemia. Second allogeneic HCT can be a curative therapeutic option for leukemia patients relapsing after their first transplant. As more targeted therapies have become available, patients that relapse after first HCT are more likely to achieve remission. Therefore, it is anticipated that there will be more candidates for second HCT with improved performance and remission status, ultimately leading to a better outcome with the second HCT.

Survival of patients with acute myeloid leukemia relapsing after allogeneic hematopoietic cell transplantation: a center for international blood and marrow transplant research study

Acute myeloid leukemia (AML) relapse after allogeneic hematopoietic cell transplantation (alloHCT) remains a major therapeutic challenge. We studied outcomes of 1788 AML patients relapsing after alloHCT (1990 to 2010) during first or second complete remission (CR) to identify factors associated with longer postrelapse survival. Median time to post-HCT relapse was 7 months (range, 1 to 177). At relapse, 1231 patients (69%) received intensive therapy, including chemotherapy alone (n = 660), donor lymphocyte infusion (DLI) ± chemotherapy (n = 202), or second alloHCT ± chemotherapy ± DLI (n = 369), with subsequent CR rates of 29%. Median follow-up after relapse was 39 months (range, <1 to 193). Survival for all patients was 23% at 1 year after relapse; however, 3-year overall survival correlated with time from HCT to relapse (4% for relapse during the 1- to 6-month period, 12% during the 6-month to 2-year period, 26% during the 2- to 3-year period, and 38% for ≥3 years). In multivariable analysis, lower mortality was significantly associated with longer time from alloHCT to relapse (relative risk, .55 for 6 months to 2 years; relative risk, .39 for 2 to 3 years; and relative risk, .28 for ≥3 years; P < .0001) and a first HCT using reduced-intensity conditioning (relative risk, .77; 95% confidence interval [CI], .66 to .88; P = .0002). In contrast, inferior survival was associated with age >40 years (relative risk, 1.42; 95% CI, 1.24 to 1.64; P < .0001), active graft-versus-host disease at relapse (relative risk, 1.25; 95% CI, 1.13 to 1.39; P < .0001), adverse cytogenetics (relative risk, 1.37; 95% CI, 1.09 to 1.71; P = .0062), mismatched unrelated donor (relative risk, 1.61; 95% CI, 1.22 to 2.13; P = .0008), and use of cord blood for first HCT (relative risk, 1.23; 95% CI, 1.06 to 1.42; P = .0078). AML relapse after alloHCT predicted poor survival; however, patients who relapsed ≥6 months after their initial alloHCT had better survival and may benefit from intensive therapy, such as second alloHCT ± DLI.

Long-term survival and late effects among one-year survivors of second allogeneic hematopoietic cell transplantation for relapsed acute leukemia and myelodysplastic syndromes

We analyzed the outcomes of patients who survived disease-free for 1 year or more after a second allogeneic hematopoietic cell transplantation (HCT) for relapsed acute leukemia or myelodysplastic syndromes between 1980 and 2009. A total of 1285 patients received a second allogeneic transplant after disease relapse; among these, 325 were relapse free at 1 year after the second HCT. The median time from first to second HCT was 17 and 24 months for children and adults, respectively. A myeloablative preparative regimen was used in the second transplantation in 62% of children and 45% of adult patients. The overall 10-year conditional survival rates after second transplantation in this cohort of patients who had survived disease-free for at least 1 year was 55% in children and 39% in adults. Relapse was the leading cause of mortality (77% and 54% of deaths in children and adults, respectively). In multivariate analyses, only disease status before second HCT was significantly associated with higher risk for overall mortality (hazard ratio, 1.71 for patients with disease not in complete remission before second HCT, P < .01). Chronic graft-versus-host disease (GVHD) developed in 43% and 75% of children and adults after second transplantation. Chronic GVHD was the leading cause of nonrelapse mortality, followed by organ failure and infection. The cumulative incidence of developing at least 1 of the studied late effects within 10 years after second HCT was 63% in children and 55% in adults. The most frequent late effects in children were growth disturbance (10-year cumulative incidence, 22%) and cataracts (20%); in adults they were cataracts (20%) and avascular necrosis (13%). Among patients with acute leukemia and myelodysplastic syndromes who receive a second allogeneic HCT for relapse and survive disease free for at least 1 year, many can be expected to survive long term. However, they continue to be at risk for relapse and nonrelapse morbidity and mortality. Novel approaches are needed to minimize relapse risk and long-term transplantation morbidity in this population.

Haploidentical stem cell transplantation for acute leukemia patients who experienced early relapse within one year after the first transplantation

To assess the safety and efficacy of allogeneic stem cell transplantation from haploidentical related donors (haplo-SCT) as 2nd transplantation for patients with early relapsed disease, we retrospectively evaluated 7 consecutive patients (median age, 42 years; range, 29-63 years) who experienced relapse within 1 year of the 1st transplantation and received haplo-SCT as a 2nd transplantation. Among the 7 patients who received haplo-SCT, 2 who were in morphologically complete remission (CR) at transplantation were conditioned with a reduced-intensity regimen, and the 5 non-CR patients were conditioned with a myeloablative regimen. Both conditioning regimens included antithymocyte globulin. Graft-versus-host disease (GVHD) prophylaxis consisted of tacrolimus and methylprednisolone. Sustained neutrophil engraftment was achieved in all 7 patients. One patient developed severe acute GVHD. Notably, only 1 patient experienced relapse, and each patient achieved longer CR duration than after the 1st transplantation. Three of the 7 patients died from treatment-related causes: acute GVHD, post-transplantation lymphoproliferative disorder, and bacterial pneumonia. At the time of analysis, the 2-year overall survival rate of these 7 patients was 42.9%. This suggests that use of haploidentical related donors is a viable alternative for 2nd transplantation and should be confirmed in larger cohorts.

Clinical outcomes of AML patients relapsing after matched-related donor and umbilical cord blood transplantation

AML relapse remains the leading cause of transplant failure among Allo-SCT recipients. A single institution study was conducted on 348 patients with AML who received an Allo-SCT from an umbilical cord blood (UCB, 222) or HLA-matched-related (RD, 126) donor between 2000-2011. Relapse after Allo-SCT occurred in 72 UCB and 32 RD transplant recipients. Three patients achieved CR after withdrawal of immune suppression with no further therapy. Fifty-two patients received intensive post-relapse therapy, defined as systemic chemotherapy (22 UCB, 7 RD), second Allo-SCT (nine UCB, two RD), or DLI±systemic chemotherapy (0 UCB, 12 RD); of these, 25% achieved CR (21% UCB vs 35% RD, P=0.16). Survival at 1 year after relapse was 22% for all patients (19% UCB vs 28% RD, P=0.36). In multivariable analysis, post-relapse mortality was lower in patients receiving intensive therapy for relapse (hazard ratio (HR)=0.4; 95% confidence interval (CI) 0.2-0.6, P<0.01) and higher in patients with peripheral blood blasts above the median (HR=3.8; 95% CI 2.2-6.6, P<0.01), active infection (HR=1.9; 95% CI 1.0-3.5, P=0.05) and non-infectious medical complications (HR=2.0; 95% CI 1.2-3.5, P=0.01). In conclusion, patients with AML relapsing after Allo-SCT who were in good-enough clinical condition to receive intensive therapy had superior short-term survival.

Second haematopoietic SCT using HLA-haploidentical donors in patients with relapse of acute leukaemia after a first allogeneic transplantation

Haploidentical haematopoietic SCT (HSCT) using T-cell-replete grafts and post-transplant high-dose CY has found increasing acceptance. Our purpose was to evaluate the feasibility and outcome of this strategy as second HSCT incorporating donor change for acute leukaemia relapse after a first allogeneic transplantation. The courses of 20 consecutive adults (median age 37 years, 12 male) with AML (n=14), ALL (n=5) and acute bi-phenotypic leukaemia (n=1) were analysed retrospectively. Conditioning consisted of fludarabine, CY and either melphalan or TBI or tresosulfan+/-etoposide. Engraftment was achieved in 17 (85%), and a second remission was induced in 15 patients (75%) on day +30. The rate of grade II-IV acute GvHD was 35%, while chronic GvHD occurred in five patients. Most commonly observed grade III-IV toxicities were mucositis (30%), hyperbilirubinemia (20%), elevation of transaminases (20%) and creatinine (20%), while invasive fungal infection affected 30%. One-year non-relapse mortality (NRM) was 36%. At a median follow-up of 17 months, estimated 1-year OS was 45%, and 1-year relapse-free survival was 33%. This strategy was feasible and allowed for successful engraftment with a moderate rate of toxicity. Early outcome and NRM are at least comparable with results after a second HSCT from HLA-matched donors without donor change at HSCT2.

Second allograft for hematologic relapse of acute leukemia after first allogeneic stem-cell transplantation from related and unrelated donors: the role of donor change

PURPOSE

To evaluate the role of a second allogeneic hematopoietic stem-cell transplantation (HSCT2) given for relapsed acute leukemia (AL) after related or unrelated first hematopoietic stem-cell transplantation (HSCT1) and to analyze the role of donor change for HSCT2 in both settings.

PATIENTS AND METHODS

We performed a retrospective registry study on 179 HSCT2s given for relapse after HSCT1 from matched related donors (n = 75) or unrelated donors (n = 104), using identical or alternative donors for HSCT2. Separate analyses were performed according to donor at HSCT1.

RESULTS

Independent of donor, 74% of patients achieved complete remission after HSCT2, and half of these patients experienced relapse again. Overall survival (OS) at 2 years was 25% ± 4% (39% ± 7% after related HSCT2; 19% ± 4% after unrelated HSCT2). Long-term survivors were observed even after two unrelated HSCT2s. Multivariate analysis for OS from HSCT2 confirmed established risk factors (remission duration after HSCT1: hazard ratio [HR], 2.37; 95% CI, 1.61 to 3.46; P < .001; stage at HSCT2: HR, 0.53; 95% CI, 0.34 to 0.83; P = .006). Outcome of HSCT2 was better after related HSCT1 than after unrelated HSCT1 (2-year OS: 37% ± 6% v 16% ± 4%, respectively; HR, 0.68; 95% CI, 0.47 to 0.98; P = .042, multivariate Cox regression). After both related and unrelated HSCT1, selecting a new donor for HSCT2 did not result in a relevant improvement in OS compared with HSCT2 from the original donor; however, donor change was not detrimental either.

CONCLUSION

After relapse from allogeneic HSCT1, HSCT2 can induce 2-year OS in approximately 25% of patients. Unrelated HSCT2 is feasible after related and unrelated HSCT1. Donor change for HSCT2 is a valid option. However, a clear advantage in terms of OS could not be demonstrated.

Treatment, risk factors, and outcome of adults with relapsed AML after reduced intensity conditioning for allogeneic stem cell transplantation

Because information on management and outcome of AML relapse after allogeneic hematopoietic stem cell transplantation (HSCT) with reduced intensity conditioning (RIC) is scarce, a retrospective registry study was performed by the Acute Leukemia Working Party of EBMT. Among 2815 RIC transplants performed for AML in complete remission (CR) between 1999 and 2008, cumulative incidence of relapse was 32% ± 1%. Relapsed patients (263) were included into a detailed analysis of risk factors for overall survival (OS) and building of a prognostic score. CR was reinduced in 32%; remission duration after transplantation was the only prognostic factor for response (P = .003). Estimated 2-year OS from relapse was 14%, thereby resembling results of AML relapse after standard conditioning. Among variables available at the time of relapse, remission after HSCT > 5 months (hazard ratio [HR] = 0.50, 95% confidence interval [CI], 0.37-0.67, P < .001), bone marrow blasts less than 27% (HR = 0.53, 95% CI, 0.40-0.72, P < .001), and absence of acute GVHD after HSCT (HR = 0.67, 95% CI, 0.49-0.93, P = .017) were associated with better OS. Based on these factors, 3 prognostic groups could be discriminated, showing OS of 32% ± 7%, 19% ± 4%, and 4% ± 2% at 2 years (P < .0001). Long-term survival was achieved almost exclusively after successful induction of CR by cytoreductive therapy, followed either by donor lymphocyte infusion or second HSCT for consolidation.

Management of relapse after allo-SCT for AML and the role of second transplantation

Relapse after allo-SCT for AML carries very poor prognosis. Second allo-SCT, although curative, is not an appropriate treatment option for a large number of relapsing patients (only 2-20% patients receive a second allo-SCT), and efforts to increase the number of patients who may benefit from a second allo-SCT are ongoing. In addition, understanding the varied biological processes that are operative in disease relapse has encouraged the development of novel therapies, and could be beneficial to patients who are currently managed conservatively with supportive care for relapsed disease. Incorporating novel combinations of drugs with immunomodulation, although theoretically attractive, should be tested in the setting of clinical trials. In this review, we discuss the currently available approaches for relapsed AML after allo-SCT.

Salvage allogeneic hematopoietic cell transplantation with fludarabine and low-dose total body irradiation after rejection of first allografts

We summarized results in 38 consecutive patients (median age=56 years) with hematologic malignancies (n=35), aplastic anemia (n=2), or renal cell carcinoma (n=1), who underwent salvage hematopoietic cell transplantation (HCT) for allograft rejection. In 14 patients, the original donors were used for salvage HCT, and, in 24 cases, different donors were used. Conditioning for salvage HCT consisted of fludarabine (Flu) and either 3 or 4 Gy total body irradiation (TBI). Sustained engraftment was achieved in 33 patients (87%). Grafts were rejected in 5 patients (13%), 4 of whom had myelofibrosis. With a median follow-up of 2 years (range: 0.3 to 7.8 years), the 2- and 4-year estimated survivals were 49% and 42%, respectively. The 2-year relapse rate and nonrelapse mortality (NRM) were 36% and 24%, respectively. The 2-year cumulative incidences of grades II-IV acute and moderate-severe chronic graft-versus-host disease (aGVHD, cGVHD) were 42% and 41%, respectively. In this cohort, TBI dose, grafts from original versus different donors, related versus unrelated donors, and HCT comorbidity scores did not have an impact on outcomes. We concluded that graft rejection after allogeneic HCT could be overcome by salvage transplantation using conditioning with Flu and low-dose TBI.