Comparison of reduced intensity and myeloablative conditioning regimens for stem cell transplantation in patients with malignancies: a meta-analysis

Predictive value of high EVI1 expression in AML patients undergoing myeloablative allogeneic hematopoietic stem cell transplantation in first CR

The EVI1 gene is a transcriptional regulator of hematopoietic stem cell self renewal and its overexpression is associated with adverse prognosis in de novo AML. Whether the overexpression of EVI1 also predicts poor outcome of AML patients undergoing myeloablative allogeneic hematopoietic stem cell transplantation (allo-HSCT) in first CR (CR1) is still unclear. Thirty-two (21.2%) out of 151 patients were categorized as high EVI1 expression (EVI1+), and 119 (78.8%) patients were categorized as low EVI1 expression (EVI1-). The frequency of EVI1+ was much higher in the adverse-risk group than the intermediate-risk group (53% vs 19%, P=0.005). EVI1+ patients were significantly likely to harbor with translocations involving the MLL gene on 11q23 (8/9). Significantly poor results were observed in the EVI1+ cohort in terms of leukemia-free survival (LFS) (in 24 months 52.6 vs 71.0%, P=0.027), overall survival (OS) (in 24 months 52.8 vs 72.4%, P=0.012), and cumulative incidence of relapse (in 24 months 39.5 vs 22.5%, P=0.013). Multivariable analysis revealed that low EVI1 expression as an independent prognostic factor favoring LFS (hazards ratio=0.47, 95% confidence interval 0.26-0.86, P=0.01) but not OS. Our results indicate high EVI1 expression might predict high risk of relapse in AML patients undergoing myeloablative allo-HSCT in CR1.

Graft-versus-host disease (GVHD) prophylaxis by using methotrexate decreases pre-engraftment syndrome and severe acute GVHD, and accelerates engraftment after cord blood transplantation

GVHD and graft failure are serious problems in CBT. PES after CBT also occurs frequently and is associated with transplantation-related complications such as acute GVHD. We reviewed medical records for 70 consecutive child CBT recipients between December 1997 and April 2015. Forty-nine patients received prophylaxis against GVHD with CsA or Tac in combination with mPSL from day +7 (mPSL group), and 21 patients received CsA or Tac with MTX on day +1 and day +3 (MTX group). Neutrophil engraftment was detected in 59 patients (84.3%). Neutrophil engraftment rate in the MTX group was significantly higher than that in the mPSL group (21/21 (100%) and 38/49 (77.6%), respectively, p = 0.027). PES developed in 35 patients, and the incidence of PES in the mPSL group was significantly higher than that in the MTX group (p = 0.036). The incidence of severe acute GVHD (grade III or IV) in the MTX group was significantly lower than that in the mPSL group (p = 0.049). Although this study was a small-scale study, the results showed that increase in the rate of engraftment and decrease in the incidence of early immune reactions such as PES and severe acute GVHD could be achieved by early commencement of immunosuppression using MTX.

Reduced-toxicity conditioning with fludarabine, once-daily intravenous busulfan, and antithymocyte globulins prior to allogeneic stem cell transplantation: results of a multicenter prospective phase 2 trial

BACKGROUND

The optimal intensity of myeloablation delivered as part of a reduced-intensity/toxicity conditioning (RIC/RTC) regimen to decrease the recurrence rate, without increasing nonrecurrence mortality (NRM), remains to be established.

METHODS

The current phase 2, prospective, multicenter trial aimed to assess the efficacy and safety of an RIC/RTC regimen based on busulfan at a dose of 130 mg/m(2) /day intravenously for 3 days, fludarabine at a dose of 30 mg/m(2) /day for 5 days, and antithymocyte globulins at a dose of 2.5 mg/kg/day for 2 days. A total of 80 patients (median age, 53 years; range, 25-64 years) with hematological malignancies were included.

RESULTS

With a median follow-up of 21 months (range, 12-36.5 months), the Kaplan-Meier estimates of overall and disease-free survival at 2 years were 62% (95% confidence interval [95% CI], 51%-73%) and 50% (95% CI, 33%-57%), respectively. The cumulative incidences of grade 2 to 4 acute graft-versus-host disease (GVHD) and chronic GVHD (all grades) were 29% (95% CI, 19%-39%) and 35% (95% CI, 24%-46%), respectively. At 2 years, the cumulative incidence of recurrence/disease progression and NRM were 44% (95% CI, 31%-56%) and 11% (95% CI, 6%-19%), respectively. Patient age, diagnosis, donor type, sex, presence of comorbidities, and the Hematopoietic cell transplantation-specific comorbidities index did not appear to have any statistically significant impact on NRM, recurrence/disease progression, disease-free survival, or overall survival.

CONCLUSIONS

The RIC/RTC regimen used in the current study appeared to be safe, with a low NRM rate at 2 years noted among high-risk patients, and efficient disease control, warranting prospective phase 3 trials.

Comparison of reduced-intensity and myeloablative conditioning regimens for allogeneic hematopoietic stem cell transplantation in patients with acute myeloid leukemia and acute lymphoblastic leukemia: a meta-analysis

Currently, the indications to perform reduced-intensity conditioning allogeneic hematopoietic stem cell transplant (RIC-HCT) are based on data derived mainly from large registry and single-centre retrospective studies. Thus, at the present time, there is limited direct evidence supporting the current practice in selecting patients with acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) for RIC versus myeloablative conditioning (MAC) transplants. To determine the relationship between dose intensity of conditioning regimen and survival outcomes after allografting in AML/ALL patients, we performed a meta-analysis of 23 clinical trials reported between 1990 and 2013 involving 15,258 adult patients that compare survival outcomes after RIC-HCT versus MAC-HCT. RIC-HCT resulted in comparable <2-year and 2-6 year overall survival (OS) rates post-transplantation even though the RIC-HCT recipients were older and had more active disease than MAC-HCT recipients. The 2-6 year progression-free survival (PFS), nonrelapse mortality, acute graft-versus-host disease (GvHD) and chronic GvHD rates were reduced after RIC-HCT, but relapse rate was increased. Similar outcomes were observed regardless of disease type and status at transplantation. Odds ratio for all outcomes remained comparable with or without performing separate analyses for the year of HCT and for retrospective versus prospective studies. Among RIC-HCT recipients, survival rates were superior if patients were in CR at transplantation. Significant inter-study heterogeneity for aGvHD data and publication bias for PFS data were observed. This meta-analysis showed no OS benefit of MAC-HCT over RIC-HCT across the entire cohort of patients suggesting that RIC-HCT could be an effective therapeutic option for AML/ALL patients who are ineligible for MAC-HCT and CR status is preferred before RIC-HCT.

Similar outcomes of peripheral blood stem cells vs. bone marrow for human leukocyte antigen-matched unrelated donor transplantation in adult patients with acute myeloid leukemia using risk-adapted graft-versus-host disease prophylaxis

BACKGROUND

In unrelated donor allogeneic stem cell transplantation (URD-SCT), most studies reported that peripheral blood stem cells (PBSC) resulted in higher incidence of acute and/or chronic graft-versus-host disease (GVHD) without survival benefits compared with bone marrow (BM). To overcome these shortcomings of PBSC, we have used a risk-adapted GVHD prophylaxis for patients that received HLA-matched URD-SCT, which was adding low-dose rabbit antithymocyte globulin (Thymoglobulin(®) , 1.25 mg/kg for 2 d) to conditioning in the transplants with PBSC and not BM.

METHODS

To determine whether this strategy is effective, we analyzed 115 adult patients with acute myeloid leukemia who received HLA-matched URD-SCT with PBSC (n = 70) or BM (n = 45) using our risk-adapted GVHD prophylaxis strategy.

RESULTS

The PBSC group showed faster neutrophil (11 d vs. 13 d; P < 0.01) and platelet (12 d vs. 18 d; P < 0.01) engraftment compared with the BM group. No difference was observed in the incidence of acute GVHD grade II-IV at 100 d (54.3% vs. 64.4%; P = 0.38) and chronic GVHD at 4 yr (65.1% vs. 60.0%; P = 0.83). Other outcomes including the incidence of relapse (30.8% vs. 31.2%; P = 0.53), non-relapse mortality (13.5% vs. 6.9%; P = 0.24), disease-free survival (55.7% vs. 61.9%; P = 0.68), and overall survival (62.2% vs. 63.2%; P = 0.96) at 4 yr were not significantly different.

CONCLUSION

Our risk-adapted GVHD prophylaxis strategy resulted in similar transplant outcomes including comparable incidence of GVHD between the PBSC and BM groups in HLA-matched URD-SCT.

Post-transplantation B cell activating factor and B cell recovery before onset of chronic graft-versus-host disease

Excessive levels of B cell activating factor (BAFF) are found in patients with active chronic graft-versus-host disease (cGVHD). In mice, BAFF has been shown to be essential for B cell recovery after myeloablation. To assess how BAFF levels relate to transplantation factors and subsequent development of cGVHD, we prospectively monitored 412 patients in the first year after allogeneic peripheral blood or bone marrow hematopoietic stem cell transplantation (HSCT) and censored data at time of cGVHD onset. In patients who did not develop cGVHD, we affirmed a temporal pattern of gradually decreasing BAFF levels as B cell numbers increase after myeloablative conditioning. In contrast, after reduced-intensity conditioning, BAFF levels remained high throughout the first post-HSCT year, suggesting that the degree of myeloablation resulted in delayed B cell recovery associated with persistence of higher BAFF levels. Given that high BAFF/B cell ratios have been associated with active cGVHD, we examined differences in early BAFF/B cell ratios and found significantly different BAFF/B cell ratios at 3 months post-HSCT only after myeloablative conditioning in patients who subsequently developed cGVHD. In addition to HSCT conditioning type, the use of sirolimus was significantly associated with higher BAFF levels after HSCT, and this also was potentially related to lower B cell numbers. Taken together, our results are important for interpreting BAFF measurements in cGVHD biomarker studies.

Infectious complications following allogeneic stem cell transplantation: reduced-intensity vs. myeloablative conditioning regimens

BACKGROUND

In allogeneic stem cell transplantation (allo-SCT), reduced-intensity conditioning (RIC) is known for producing less regimen-related toxicity. However, whether or not RIC reduces the risk for infection and infection-related mortality (IRM) remains controversial.

METHODS

We retrospectively analyzed infectious episodes and IRMs after allo-SCTs by time period and by the intensity of the conditioning regimen (RIC [n = 81] vs. myeloablative conditioning, MAC [n = 150]).

RESULTS

The cumulative incidence of any kind of infection was lower in the RIC group through the entire period (72% vs. 87%; P = 0.007). The onset of infections was deferred in the RIC group as compared with the MAC group (P = 0.012). Bacteremia occurred less frequently in the RIC group through the entire period (5% vs. 14%; P = 0.044). However, the incidences of cytomegalovirus reactivation and disease, herpes zoster, virus-associated hemorrhagic cystitis, and invasive fungal infection were not different between the two groups. Furthermore, there was no difference in relapse-free survival and IRM between the two conditioning regimens.

CONCLUSION

Careful monitoring and appropriate preventive/therapeutic strategies for infectious complications, comparable to those for allo-SCT recipients with MAC, should also be applied to those with RIC, especially after engraftment.

Sclerotic-type chronic GVHD of the skin: clinical risk factors, laboratory markers, and burden of disease

Chronic GVHD is one of the most severe complications of allogeneic HSCT. The sclerotic skin manifestations of cGVHD (ScGVHD) result from inflammation and fibrosis of the dermis, subcutaneous tissue, or fascia, leading to significant functional disability. Risk factors and clinical markers associated with ScGVHD remain largely unexamined. By using a single-visit, cross-sectional design, we evaluated 206 patients with cGVHD at the National Institutes of Health. Most patients manifested severe (ie, 63% National Institutes of Health score "severe"), refractory disease (median treatments = 4). ScGVHD was detected in 109 (52.9%) patients. ScGVHD was associated with greater platelet count (P < .001) and C3 (P < .001), and decreased forced vital capacity (P = .013). Total body irradiation (TBI) was associated with development of ScGVHD (P = .002). TBI administered in reduced-intensity conditioning was most strongly associated with ScGVHD (14/15 patients, P < .0001). Patients with ScGVHD had significant impairments of joint range of motion and grip strength (P < .001). Greater body surface area involvement was associated with poorer survival (P = .015). We conclude that TBI, particularly in reduced-intensity regimens, may be an important risk factor for ScGVHD. Widespread skin involvement is associated with significant functional impairment, distressing symptoms, and diminished survival. This trial is registered at http://www.clinicaltrials.gov as NCT00331968.