Safety and efficacy of total body irradiation, cyclophosphamide, and cytarabine as a conditioning regimen for allogeneic hematopoietic stem cell transplantation in patients with acute lymphoblastic leukemia

Risk factors for fatal cardiac complications after allogeneic hematopoietic cell transplantation: Japanese Society for Transplantation and Cellular Therapy transplant complications working group

Fatal cardiac complications can occur from the early to late phases after hematopoietic cell transplantation (HCT). Herein, the Japanese transplant registry database was used to retrospectively analyze health records of 33,791 allogeneic HCT recipients to elucidate the pathogenesis and risk factors involved. Overall, 527 patients died of cardiac complications at a median of 130 (range 0-3924) days after HCT. The cumulative incidence of fatal cardiac complications was 1.2% (95% confidence interval [CI]: 1.0-1.3) and 1.6% (95% CI: 1.5-1.8) at 1 and 5 years after HCT, respectively. Fatal cardiovascular events were significantly associated with an HCT-specific comorbidity index (HCT-CI) score of ≥1 specific to the three cardiovascular items, lower performance status, conditioning regimen cyclophosphamide dose of >120 mg/kg, and female sex. Cardiovascular death risk within 60 days after HCT was associated with the type of conditioning regimen, presence of bacterial or fungal infections at HCT, and number of blood transfusions. Contrastingly, late cardiovascular death beyond 1 year after HCT was associated with female sex and older age. Lower performance status and positive cardiovascular disease-related HCT-CI were risk factors for cardiac complications in all phases after HCT. Systematic follow-up may be necessary according to the patients' risk factors and conditions.

Intensified conditioning regimens improved disease-free survival and engraftment after unrelated single-unit cord blood transplantation but not after matched sibling or matched unrelated donor allogeneic hematopoietic cell transplantation

The impact of conditioning intensity on different donor groups has been unclear in allogeneic transplantation. The objective of this study was to clarify the effect of conditioning intensity on disease-free survival (DFS), relapse, non-relapse mortality (NRM), neutrophil engraftment, and graft-versus-host disease for each donor type. We retrospectively evaluated the effect of conditioning intensity on transplant outcomes for patients with acute leukemia or myelodysplastic syndrome aged between 16 and 60 years in Japan using the transplant conditioning intensity (TCI) scoring system. A total of 8526 patients who received first allogeneic transplantation from 6/6 antigen-matched sibling donor (MSD, n = 2768), 8/8 allele-matched unrelated donor (MUD, n = 2357), and unrelated single-cord blood (UCB, n = 3401) were eligible for the analyses. Compared to conditioning with TCI score 4.0, which was corresponds to conventional myeloablative conditioning, including cyclophosphamide with total body irradiation 12 Gy or busulfan 12.8 mg, and was considered as the reference group in the multivariate analyses, intensified conditioning with TCI score ≥4.5 improved DFS (hazard ratio [HR],0.81, P < 0.001) and relapse rate (HR, 0.70, P < 0.001) but only after UCB transplants and not MSD and MUD transplants. In contrast, NRM was higher after intensified conditioning with TCI score ≥4.5 for MSD (HR, 1.39, P = 0.008) and MUD (HR, 1.47, P = 0.002) transplants but not UCB transplants (HR, 1.12, P = 0.240). Neutrophil engraftment was also significantly higher after intensified conditioning with TCI score ≥4.5 but only for UCB transplants (HR, 1.24, P < 0.001), whereas it was significantly lower after reduced-intensity conditioning with TCI score ≤3.5 for MSD transplants only (HR, 0.82, P < 0.001). These data demonstrated that an intensified conditioning regimen improved survival and engraftment rate only after a UCB transplants. Therefore, TCI scoring system could enable the optimization of conditioning intensity according to donor type, particularly in terms of survival and engraftment.

Outcomes of allogeneic haematopoietic stem cell transplantation with intensity-modulated total body irradiation by helical tomotherapy: a 2-year prospective follow-up study

BACKGROUND AND OBJECTIVES

Intensity-modulated radiation therapy (IMRT) helps achieve good radiation dose conformity and precise dose evaluation. We conducted a single-centre prospective study to assess the safety and feasibility of total body irradiation with IMRT (IMRT-TBI) using helical tomotherapy in allogeneic haematopoietic stem cell transplantation (allo-HSCT).

PATIENTS AND METHODS

Thirty-nine adult patients with haematological malignancy (acute lymphoblastic leukaemia [n = 21], chronic myeloid leukaemia [n = 6], mixed phenotype acute leukaemia [n = 5], acute myeloid leukaemia [n = 4], and malignant lymphoma [n = 3]) who received 12 Gy IMRT-TBI were enrolled with a median follow-up of 934.5 (range, 617-1254) d. At the time of transplantation, 33 patients (85%) achieved complete remission. The conditioning regimen used IMRT-TBI (12 Gy in 6 fractions twice daily, for 3 d) and cyclophosphamide (60 mg/kg/d, for 2 d), seven patients were combined with cytarabine, and five with etoposide. We set dose constraints for the lungs, kidneys and lens as the organs at risk.

RESULTS

The mean doses for the lungs and kidneys were 7.50 and 9.11 Gy, respectively. The mean maximum dose for the lens (right/left) was 5.75/5.87 Gy. The 2-year overall survival (OS), disease-free survival (DFS), cumulative incidence of relapse (CIR) and non-relapse mortality (NRM) were 69, 64, 18 and 18%, respectively. Thirty-six patients developed early adverse events (AEs) (including four patients with Grade 3/4 toxicities), most of which were reversible oral mucositis and may partially have been related to IMRT-TBI. However, the incidence of toxicity was comparable to conventional TBI-based conditioning transplantation. None of the patients developed primary graft failure, or Grade III-IV acute graft-versus-host disease (GVHD). In late complications, chronic kidney disease was observed in six patients, a lower incidence compared to conventional TBI-based conditioning transplantation. No radiation pneumonitis or cataracts were observed in any of the patients.

CONCLUSIONS

IMRT-TBI is safe and feasible for haematological malignancies with acceptable clinical outcomes.KEY MESSAGESIMRT-TBI-helical tomotherapy aids in accurate dose calculation and conformity.It could be used without any considerable increase in the rate of TBI-related AEs.Allo-HSCT with IMRT-TBI may be an alternative to conventional TBI for clinical use.

Radiation induced delayed transverse myelitis and neurological deficit at tertiary care center

Background

Transverse myelitis is a rare spinal cord inflammation with absence of a compression. It varies in presentation based on the pathology location, and mainly causes a combined deficit of motor, sensory, and autonomic functions. History, physical examination, and other diagnostic tests including blood tests and an MRI are important tools to establish a diagnosis.

A thorough neurological evaluation helps localize the affected region of the spinal cord. The management includes rehabilitation as any other spinal cord injury. If very severe, a multidisciplinary rehabilitation program will be required.

Presentation

We explain a case in which a 43-year-old male patient, known to have chronic myelogenous leukemia (CML), on Imatinib (a tyrosine kinase inhibitor), started complaining of back pain at the level of the 10th rib. Different tests were made including a PET-CT (Positron Emission Tomography-Computed Tomography) which showed hypermetabolic bony lytic lesion in the left mandible at the level of temporomandibular joint, destruction of the 10th rib, and no evidence of spinal cord compression. Other etiologies were excluded, making transverse myelitis due to radiation for the patient's CML on top of the differential diagnosis.

Conclusion

A thorough physical examination and diagnostic tests are important tools to exclude other etiologies of complex neurological deficit in a patient with CML.

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Transverse myelitis can be a possible complication post-radiation for CML treatment.

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Careful history taking, meticulous physical examination, and investigations are necessary.

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Avoid delaying intervention once a diagnosis has been made to avoid neurological impairment.

Phase 1 study of plerixafor in combination with total body irradiation-based myeloablative conditioning for allogeneic hematopoietic stem cell transplantation

Plerixafor, a CXCR4 inhibitor, has the potential to mobilize leukemic cells, which may contribute to their chemosensitization. This phase 1 study evaluated the safety of myeloablative conditioning combined with plerixafor for allogeneic hematopoietic stem cell transplantation (HSCT). Patients with high-risk leukemia undergoing allogeneic HSCT after total body irradiation (TBI, 12 Gy)-based myeloablative conditioning were eligible; 9 patients were enrolled. The study was performed using a 3 + 3 design with an escalating total dose of plerixafor. Plerixafor was given subcutaneously 8 h before TBI and chemotherapeutic agents. Plerixafor was successfully escalated to the maximum dose (0.72 mg/kg) without dose-limiting toxicities. Underlying diseases were acute myelogenous and lymphoblastic leukemia, chronic myeloid leukemia, and myelodysplastic syndrome. As adverse events, plerixafor administration was associated with transient Grades 2-3 diarrhea (n = 7) and abdominal pain (n = 4). In 6 patients, leukemic cell mobilization into the peripheral blood by plerixafor was confirmed by a morphological or molecular method. All patients achieved neutrophil engraftment and 5 were alive in remission at a follow-up after 30-40 months. Plerixafor-combined myeloablative conditioning for allogeneic HSCT was well tolerated. Leukemic-cell mobilization into peripheral blood was observed in half of the patients. Further study is required to evaluate the efficacy and safety of this concept.

Safety of total body irradiation using intensity-modulated radiation therapy by helical tomotherapy in allogeneic hematopoietic stem cell transplantation: a prospective pilot study

Total body irradiation using intensity-modulated radiation therapy total body irradiation (IMRT-TBI) by helical tomotherapy in allogeneic hematopoietic stem cell transplantation (allo-HSCT) allows for precise evaluation and adjustment of radiation dosage. We conducted a single-center pilot study to evaluate the safety of IMRT-TBI for allo-HSCT recipients. Patients with hematological malignancies in remission who were scheduled for allo-HSCT with TBI-based myeloablative conditioning were eligible. The primary endpoint was the incidence of adverse events (AEs). Secondary endpoints were engraftment rate, overall survival, relapse rate, non-relapse mortality, and the incidence of acute and chronic graft-versus-host disease (aGVHD and cGVHD, respectively). Between July 2018 and November 2018, ten patients were recruited with a median observation duration of 571 days after allo-HSCT (range, 496-614). D80% for planning target volume (PTV) in all patients was 12.01 Gy. Average D80% values for lungs, kidneys and lenses (right/left) were 7.50, 9.03 and 4.41/4.03 Gy, respectively. Any early AEs (within 100 days of allo-HSCT) were reported in all patients. Eight patients experienced oral mucositis and gastrointestinal symptoms. One patient experienced Bearman criteria grade 3 regimen-related toxicity (kidney and liver). All cases achieved neutrophil engraftment. There was no grade III-IV aGVHD or late AE. One patient died of sinusoidal obstruction syndrome 67 days after allo-HSCT. The remaining nine patients were alive and disease-free at final follow-up. Thus, IMRT-TBI was well tolerated in terms of early AEs in adult patients who underwent allo-HSCT; this warrants further study with longer observation times to monitor late AEs and efficacy.

Comparing the outcomes between TMLI and non-TMLI conditioning regimens for adult high-risk acute lymphoblastic leukemia patients undergoing allogeneic hematopoietic stem cell transplantation: a single-center experience

This study aimed to retrospectively evaluate the outcomes of adult patients with high-risk acute lymphoblastic leukemia (ALL) who received allogeneic hematopoietic stem cell transplantation (allo-HSCT) with either total marrow and lymphoid irradiation (TMLI)-containing or non-TMLI conditioning regimen. Seventy adult patients with high-risk ALL who received allo-HSCT were enrolled in this study and divided into two groups based on the conditioning regimen type (TMLI group: n = 29 and non-TMLI group: n = 41). We noted significant statistical differences in the 1-year estimated cumulative incidence of relapse (25% vs. 46.5%, p = 0.018), the 1-year estimated overall survival (73.1% vs. 52.6%, p = 0.033) and disease-free survival (65.2% vs. 48.2%, p = 0.026) but found no considerable difference in transplant-related mortality (12% vs. 13.4%, p = 0.619) between patients in the TMLI and non-TMLI groups. The TMLI-containing regimen is safe and alternative for patients with high-risk ALL undergoing allo-HSCT.

Irradiation free conditioning regimen is associated with high relapse rate in Egyptian patients with acute lymphoblastic leukemia following allogeneic hematopoietic stem cell transplantation

Background

Allogeneic hematopoietic stem cell transplantation (Allo-HSCT) is a curative treatment for adult patients with acute lymphoblastic leukemia (ALL). Cyclophosphamide plus total body irradiation (TBI/Cy) or plus busulfan (Bu/Cy) is a widely used pre-transplant conditioning regimen for ALL. We retrospectively compared the overall survival (OS), disease-free survival (DFS), and other transplant outcomes of allo-HSCT in 119 adult patients with ALL who received an HLA-matched sibling allo-HSCT using TBI-based versus non-TBI-based conditioning regimens. Patients were divided into two groups by their conditioning regimen: TBI/Cy or Bu/Cy.

Results

Median OS was 11 months in the TBI/Cy group and 6.2 months in the Bu/Cy group. Median DFS was 11.1 months in the TBI group versus 6.8 months in the Bu group, without a statistically significant difference. A higher risk of relapse was observed with the Bu/Cy regimen (HR 2.709, CI 95% 1.106 to 6.638, p = 0.029). Patients who received a transplant in ≥ CR2 were associated with poor DFS.

Conclusion

Despite the high relapse rate in the non-TBI regimen (Bu/Cy), both regimens had no statistically significant differences in OS, DFS, and NRM. Additional prospective studies are indeed warranted to evaluate the long-term outcomes of radiation-free regimens, including oral and intravenous busulfan, and compare these regimens with TBI-based ones.

Better outcomes of modified myeloablative conditioning without antithymocyte globulin versus myeloablative conditioning in cord blood transplantation for hematological malignancies: A retrospective (development) and a prospective (validation) study

Cord blood transplantation (CBT) is an effective option for treating hematological malignancies, but graft failure (GF) remains the primary cause of therapy failure. Thus, based on myeloablative conditioning (MAC) of busulfan with cyclophosphamide (Bu/Cy) or total body irradiation with Cy (TBI/Cy), fludarabine (Flu) was added to Bu/Cy and cytarabine (CA) to TBI/Cy for a modified myeloablative conditioning (MMAC). To compare the prognosis of MMAC with MAC, we conducted a retrospective study including 58 patients who underwent CBT with MAC or MMAC from 2000 to 2011. Neutrophil and platelet engraftment rate, overall survival (OS) and disease free survival (DFS) were significantly higher in the MMAC group (adjusted hazard ratio [HR], 2.58, 2.43, 0.36 and 0.37; p < 0.01, p = 0.01, p = 0.02 and p = 0.02, separately). Nonrelapse mortality (NRM) was comparable (p = 0.183). To validate the outcomes noted in the MMAC group, we conducted a prospective single‐arm clinical trial including 188 patients who underwent CBT with MMAC from 2011 to 2015. Engraftment rate, survival and NRM of the MMAC group in the prospective trail (MMAC‐P) were similar to the MMAC group in the retrospective study (MMAC‐R). This study is the first to demonstrate the superiority of MMAC to MAC in CBT for hematological malignancies.

What's new?

Cord blood transplants can help patients with blood cancer, but too often, the transplant fails due to immune rejection or other problems. Typically, patients receive myeloablative conditioning (MAC) prior to CBT, but more intense regimen might improve transplant success. Here, the authors compared the success of modified myeloablative conditioning (MMAC) with conventional MAC by looking at 58 patients over an 11‐year period. They then followed up with a four‐year prospective study, including 188 patients who received cord blood transplant with MMAC. The modified conditioning regimen boosted graft success and improved survival of patients with hematological cancers.

Idarubicin-intensified BUCY2 conditioning regimen improved survival in high-risk acute myeloid, but not lymphocytic leukemia patients undergoing allogeneic hematopoietic stem cell transplantation: A retrospective comparative study

The intensity of conditioning regimen is highly correlated with outcomes of allogeneic hematopoietic stem cell transplantation (allo-HSCT). We have previously reported that idarubicin (IDA) intensified BUCY2 regimen could reduce relapse and improve survival for high-risk hematological malignancies undergoing allo-HSCT. However, there is no published study comparing the efficacy of IDA-BUCY2 regimen for high-risk acute myeloid leukemia (AML) versus acute lymphocytic leukemia (ALL). We further retrospectively compared therapeutic outcomes of intensified conditioning regimen on 140 high-risk AML and ALL patients in the data analyses. IDA 15mg/m(2)/d was administered by continuous infusion from day -11 to -9, followed by intravenous injection of busulfan (BU) (3.2mg/kg/d) from day -6 to -4, and intravenous injection of cyclophosphamide (CY) (1.8g/m(2)/d) from day -3 to -2 in IDA-BUCY2 regimen. For high-risk AML, cumulative probabilities of 3-year relapse rates in IDA-BUCY2 and traditional BUCY2 regimens were 16.9%, 43.3% (P=0.016). Cumulative probabilities of 3-year overall survival (OS) and disease-free survival (DFS) were 69.2% vs 44.0% (P=0.024), and 66.9% vs 38.2% (P=0.01). However, two regimens showed no significant differences for high-risk ALL. Multivariate analysis also indicated that IDA intensified BUCY2 conditioning was the favorable variable to reduce relapse and elevate survival for high-risk AML patients. In conclusion, IDA-BUCY2 regimen reduces relapse and improves survival for high-risk AML undergoing allo-HSCT, but not presenting uniform therapeutic effects for high-risk ALL.

The Efficacy of an Oral Elemental Diet in Patients Undergoing Hematopoietic Stem Cell Transplantation

Objective Conditioning regimens for hematopoietic stem cell transplantation (HSCT) are well known to cause severe gastrointestinal toxicities that often disturb the oral intake of the patients followed by poor nutrition and life-threatening infection. An oral elemental diet (ED) is an easily consumed and assimilated form of liquid nutrients mainly composed of amino acids. It alleviates the digestive loading from the intestine and is mainly used for enteral nutritional support in patients with Crohn's disease. We herein report, for the first time, the efficacy of ED for patients undergoing HSCT. Methods We evaluated the efficacy of ED in a prospective cohort study. The primary endpoint for this study was the hospitalization period. The secondary endpoint was the occurrence of oral mucositis, nausea, diarrhea and fever. Patients A total of 73 patients were consecutively enrolled between March 2011 and March 2013. Twenty-three patients underwent autologous HSCT and 50 patients underwent allogeneic HSCT. The first 21 patients did not receive ED (non-ED group; NEG) while in the successive 52 patients (ED group; EG), oral ED was started before conditioning and was continued until 28 days after transplantation. Results The patient characteristics were similar between the two groups. The mean duration of ED administration for EG was 28.7 days (range, 3-37 days), and the mean total-dose of ED administration was 1904 g (range, 240-2,960 g). The median hospitalization period was significantly shorter in EG compared to NEG, (34 days vs. 50 days; p=0.007). Grade 3-4 oral mucositis occurred less in EG than NEG (25% vs. 48%; p=0.06). Conclusion Oral ED may promote an early mucosal recovery and thereby shorten the duration of hospitalization.

Comparison of outcomes of idarubicin intensified TBI-CY and traditional TBI-CY conditioning regimen for high-risk acute lymphoblastic leukemia undergoing allogeneic hematopoietic stem cell transplantation: A single center experience

High-risk acute lymphoblastic leukemia (ALL) carries a very poor prognosis, even after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Exploring novel conditioning regimen to more effectively eliminate leukemic clone while not alter transplant-related mortality (TRM) has become focus of attention. We retrospectively evaluated outcomes of 87 high-risk ALL patients undergoing allo-HSCT: 47 patients received idarubicin (IDA) intensified TBI-CY and 40 patients received traditional TBI-CY regimen. In IDA intensified group, patients received TBI (8Gy) on day-8, IDA of 15mg/m2/d from day-6 to -5, followed by CY (60mg/kg/d) on day-3 to -2. The cumulative incidence of relapse was significantly lower in IDA intensified group compared with TBI-CY group (P=0.018). Oropharyngeal mucositis was observed more frequent in IDA intensified group (P=0.013), while not followed by increased TRM. Very high-risk ALL patients benefit from IDA intensified regimen with only two of eight patients in no remission (NR) pre-transplantation and two of twelve ph+ALL patients relapsed after transplantation. After a median follow-up for all survivors of 21 months (range, 12-53 months), 2-year estimated OS and DFS was 66.2% vs 45.3% (P=0.031) and 62.5% vs 43.5% (P=0.044), respectively. In conclusion, IDA intensified TBI-CY regimen may reduce relapse while not increasing TRM, providing better survival for high-risk ALL patients undergoing allo-HSCT.

Clinical significance of the administration of cytarabine or thiotepa in addition to total body irradiation and cyclophosphamide for allogeneic hematopoietic cell transplantation in patients with acute leukemia

A multicenter retrospective study was performed to determine the significance of adding cytarabine (CA) or thiotepa (TT) in the context of total body irradiation (TBI) and cyclophosphamide (CY). A total of 322 patients who underwent allogeneic hematopoietic cell transplantation (HCT) were distributed to the following three groups: TBI/CY (n = 75), TBI/CY/CA (n = 77), and TBI/CY/TT (n = 170). In the TBI/CY/TT group, 164 of patients (96 %) received HCT during the previous year (2000-2005). Multivariate analysis revealed that the TBI/CY/TT group demonstrated a trend of poorer survival rate than the TBI/CY group, [hazard ratio (HR) = 1.49, 95 % confidence interval (CI) 0.99-2.24, P = 0.055] with a higher non-relapse mortality (NRM) (HR = 2.34, 95 % CI 1.35-4.06, P = 0.002) rates, while TBI/CY/CA group demonstrated similar outcomes. Even in the subgroup analyses of disease type or disease risk, the outcomes with intensified conditioning regimens were not superior to those with TBI/CY. In conclusion, although the significant bias has to be carefully considered, the clinical benefit of adding CA or TT to the TBI/CY regimen was not demonstrated.

Efficiency of high-dose cytarabine added to CY/TBI in cord blood transplantation for myeloid malignancy

Cord blood transplantation (CBT) is an effective therapeutic option for adults with acute myelogenous leukemia (AML) and myelodysplastic syndrome (MDS) after the conventional cyclophosphamide and total body irradiation (CY/TBI) regimen, but posttransplant relapse is still of high importance. High-dose cytarabine (HDCA) can be added to CY/TBI for an intensified regimen; however, its additional effects have not yet been completely elucidated. Therefore, we conducted a cohort study to compare the prognosis of HDCA/CY/TBI (n = 617) and CY/TBI (n = 312) in CBT for AML/MDS, using a Japanese transplant registry database. The median age was 40 years, and 86.2% of the patients had AML; high-risk disease was observed in 56.2% of the patients. The median follow-up period after CBT was approximately 3.5 years. Overall survival was significantly superior in the HDCA/CY/TBI group (adjusted hazard ratio [HR], 0.56; 95% confidence interval [CI], 0.45-0.69; P < .01), and tumor-related mortality was lower (HR, 0.50; P < .01). The incidence of grade II to IV acute graft-vs-host disease (aGVHD) and chronic GVHD was significantly higher in the HDCA/CY/TBI group (HR, 1.33 and 2.30, respectively), but not grade III to IV aGVHD. Incidence of infectious episodes showed no significant difference. Nonrelapse mortality was not increased by the addition of HDCA. Higher-dose CA (12 rather than 8 g/m(2)) was more effective, particularly in patients at high-risk for disease. This study is the first to show the superiority of HDCA/CY/TBI to CY/TBI in CBT for AML/MDS. A large-scale prospective study is warranted to establish new conditioning regimens including HDCA administration.

Low Dose Total Body Irradiation Combined With Recombinant CD19-Ligand × Soluble TRAIL Fusion Protein is Highly Effective Against Radiation-Resistant B-Precursor Acute Lymphoblastic Leukemia in Mice

In high-risk remission B-precursor acute lymphoblastic leukemia (BPL) patients, relapse rates have remained high post-hematopoietic stem cell transplantation (HSCT) even after the use of very intensive total body irradiation (TBI)-based conditioning regimens, especially in patients with a high “minimal residual disease” (MRD) burden. New agents capable of killing radiation-resistant BPL cells and selectively augmenting their radiation sensitivity are therefore urgently needed. We report preclinical proof-of-principle that the potency of radiation therapy against BPL can be augmented by combining radiation with recombinant human CD19-Ligand × soluble TRAIL (“CD19L–sTRAIL”) fusion protein. CD19L–sTRAIL consistently killed radiation-resistant primary leukemia cells from BPL patients as well as BPL xenograft cells and their leukemia-initiating in vivo clonogenic fraction. Low dose total body irradiation (TBI) combined with CD19L–sTRAIL was highly effective against (1) xenografted CD19⁺ radiochemotherapy-resistant human BPL in NOD/SCID (NS) mice challenged with an otherwise invariably fatal dose of xenograft cells derived from relapsed BPL patients as well as (2) radiation-resistant advanced stage CD19⁺ murine BPL with lymphomatous features in CD22ΔE12xBCR-ABL double transgenic mice. We hypothesize that the incorporation of CD19L–sTRAIL into the pre-transplant TBI regimens of patients with very high-risk BPL will improve their survival outcome after HSCT.

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CD19L–sTRAIL plus low dose radiation kills leukemia-initiating cells.

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CD19L–sTRAIL plus low dose TBI is very well tolerated in mice.

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CD19L–sTRAIL plus low dose TBI is very effective in mouse models of BPL.

Comparison of total body irradiation plus cyclophosphamide with busulfan plus cyclophosphamide as conditioning regimens in patients with acute lymphoblastic leukemia undergoing allogeneic hematopoietic stem cell transplant

Conditioning regimens used during stem cell transplant provide prolonged control or cure of the disease in patients with acute lymphoblastic leukemia (ALL). In this study, we present a comparison of treatment results for 95 patients with ALL who underwent allogeneic hematopoietic stem cell transplant (AHSCT) with total body irradiation plus cyclophosphamide (TBI + Cy) or busulfan plus cyclophosphamide (Bu + Cy) as conditioning regimen. Median age was 25 (range: 9-54) years. Median follow-up was 24 (range: 3-107) months. Median overall survival (OS) was found to be 29 months. Median event-free survival (EFS) was 9 months. Median OS was 37 months in the TBI + Cy arm, while it was 12 months in the Bu + Cy arm, suggesting a significant advantage favoring the TBI + Cy arm (p = 0.003). Median EFS was 13 months in the TBI + Cy arm, while it was 4 months in the Bu + Cy arm, indicating a significant difference (p = 0.006). In univariate and multivariate analysis, it was found that high OS and EFS were significantly correlated with TBI + Cy conditioning regimen and lack of transplant-related mortality (p < 0.05). The TBI + Cy conditioning regimen was found to be superior to the Bu + Cy regimen in patients with ALL undergoing AHSCT regarding both OS and EFS.

An acute transverse myelitis attack after total body irradiation: a rare case

Total body irradiation (TBI) combined with chemotherapy is widely used as a pretreatment regimen of bone marrow transplantation (BMT) in hematologic disorders. Late complications related to TBI as part of the conditioning regimen for hematopoietic stem cell transplantation have been revealed. Acute transverse myelitis (ATM) is a neurological syndrome characterized by disorder of motor, sensorial, and autonomic nerves, and tracts at medulla spinalis, which is resulted from involvement of spinal cord. In this paper, we presented an ATM attack developed after TBI in a patient with acute lymphoblastic leukemia (ALL) as it is a rarely seen case.

Cyclophosphamide promotes engraftment of gene-modified cells in a mouse model of Fanconi anemia without causing cytogenetic abnormalities

A major hurdle for hematopoietic stem cell (HSC) gene therapy for inherited bone marrow disorders, including Fanconi anemia (FA), is adequate engraftment of gene-modified cells. A phenotypic defect in DNA repair renders FA patients sensitive to alkylating agents such as cyclophosphamide (Cy); however, at lower doses, Cy is well tolerated in the FA transplant setting. We tested whether non-alkylating agents could replace Cy for pretransplant conditioning to enhance engraftment of FANCA gene-modified hematopoietic cells. We compared Cy preconditioning with fludarabine (Flu) or cytarabine (AraC) or no conditioning as a control in fanca ( -/- ) mutant mice receiving gene-modified bone marrow cells. Only mice conditioned with Cy exhibited appreciable engraftment of gene-modified cells by PCR and resistance to mitomycin C (MMC). Cy administration following transplantation increased gene marking levels in all animals treated, but highest gene marking and corresponding MMC resistance were observed in mice receiving Cy pre- and posttransplantation. Importantly, no cytogenetic abnormalities were observed in Cy-treated mice. We conclude that Cy is an effective and superior preparative regimen with respect to engraftment of lentivirus-transduced cells and functional correction in fanca ( -/- ) mice. Thus, appropriately dosed Cy may provide a suitable conditioning regimen for FA patients undergoing HSC gene therapy.