Hyperfractionated Total Body Irradiation Research Articles

Regulatory T Cells for Acute Graft Versus Host Disease Prevention

BACKGROUND GVHD remains a major cause of morbidity and mortality after allo HSCT. The past few years have shown a number of successful advances in cellular therapies for the treatment of hematologic malignancies. It is logical to expand the use of these therapies earlier, in strategies aimed at prevention. Several studies showed that regulatory T cells (Treg) can reduce the incidence of aGVHD. METHODS Studies were identified using electronic databases (Medline, Embase, and Cochrane). Preclinical studies were excluded. Data analysis was performed using GraphPad Software 8.4.2. RESULTS 160 patients were identified from 7 clinical studies. 85% of the patients had acute leukemia and were in complete remission at the time of transplant. Tregs were isolated from either UCB or PB. Tregs were expanded ex-vivo using IL-2, CD3/CD28 ab coated beads and K562 cells in three studies (n=40). 1.Ex-vivo expanded Treg: In a phase I study (Brunstein et al) of UCB-derived Tregs in 23 pts undergoing double umbilical cord transplantation, Tregs were cultured with antiCD3/anti CD28 and IL-2. Ex-vivo expanded Tregs were given on day+1 and day+15. Eighteen pts received Treg cells at dose of >3x106 cells/kg. Grade II-IV aGvHD was seen in 39% of pts who received ≥3x106 cells/kg vs 43% in historical controls. In this study, CsA+MMF or sirolimus+MMF were used for GvHD prophylaxis. In a follow up study of 11 patients, Tregs were markedly expanded using K562 cells. Higher Treg doses were achieved up to 100x106cells/kg and the median proportion of CD4+CD127-FOXP3+ within the infused products was 87%. Grade II-IV aGVHD was 9% at 100 days vs 45% in control group. Treg cells were not detected in the peripheral blood after 14 days of infusion. In a phase II study (Kellner et al; Zeng et al), three of six pts undergoing PB MUD received ex-vivo expanded UCB-derived Tregs 1x106/kg at day-1. All developed aGVHD due to the high donor Tcon cells in the graft with donor Tcon:UCB Treg ratio as high as 356:1. Sixth patient was given 1x107 cells/kg Tregs in the presence of anti CD3/28 microbeads and IL-2 with Treg:Tcon ratio of 1:40. No aGVHD was observed in this patient compared to the others who received Treg at the dose of 1x106cells/kg. 2.Unexpanded Treg: In a study (Di Ianni et al) involving 26 high risk leukemia pts undergoing haplo-transplant with TBI based conditioning, 21 pts were infused with donor Tregs at a dose of 2x106 cells/kg and five pts were infused with Treg at a dose of 4x106 cells/kg on day -4, followed by Tcon infusion ranging from 0.5x106 to 2x106 cells/kg on day 0. No post-transplant immune suppression was given. Grade II-IV aGVHD was observed in 2 out of 26 patients who received 4x106cells/kg Tregs and 2x 106cells/kg Tcons. No GVHD was observed in pts who received 2x106cells/kg Tregs followed by 0.5-1x106 cells/kg Tcons. A phase II study by the same group (Martelli et al) reported on an additional 17 pts who received Tregs (2x106cells/kg) at day-4 co-infused with Tcon (1x106cells/kg) at day 0. Six of 41 (15%) evaluable pts developed grade II-IV aGVHD (vs 11% in historical cohort) with two pts requiring a short course of immunosuppression. Incidence of relapse was lower in Treg group than historical controls (5% vs 21%). In a phase I/II study (Meyer et al), 12 pts with hematological malignancies who underwent HLA-matched transplantation received purified Tregs (1-3x106cells/kg) on day0 followed by Tcon (1-3x106cells/kg) on day+2. GVHD was seen in 80% of pts with 50% being grade III in pts who received frozen Tregs. Upon revising protocol, 7 pts were given fresh Treg. The patients also received either tacrolimus or sirolimus for immunosuppression. None of 7 pts in revised cohort developed GVHD. Recent study applied hyper-fractionated TBI to the conditioning regimen in 12 pts out of 40 to further reduce leukemia relapse in Treg/Tcon based haplo-HSCT. Treg was administered at the dose of 2x106cells/kg and Tcon at 1x106cells/kg. No post-transplant GvHD prophylaxis was given. Grade II-IV aGVHD was observed in 12 pts. CONCLUSION These studies suggest that Treg therapy may represent an effective prevention strategy against acute GvHD (figure 1). Stimulated Treg expansion strategies and higher doses of Treg appear to be associated with lower incidence of aGVHD. Treg infusion was well-tolerated without serious adverse events. Large prospective clinical trials are warranted in order to establish the optimal infusion dose, optimal expansion strategies and dosing schedule. Disclosures No relevant conflicts of interest to declare.

Treg/Tcon Immunotherapy and High Dose Marrow Irradiation Ensure Full Control of Leukemia Relapse in Haploidentical Transplantation

Allogeneic hematopoietic stem cell transplantation (HSCT) is the most powerful therapy for patients with high risk of relapse. In spite of that, no matter the donor source or conditioning regimen used, leukemia relapse is still the leading cause of HSCT failure. In HLA-haploidentical HSCT, we recently applied a clinical protocol consisting of total body irradiation (TBI)-based conditioning regimen and a peripheral blood CD34+ cell graft combined with the adoptive transfer of naturally occurring regulatory T cells (Tregs) and conventional T cells (Tcons). No post-transplant pharmacologic GvHD prophylaxis was given. Such protocol was associated with low GvHD and relapse rate (Martelli et al., Blood 2014). To further reduce leukemia relapse in Treg/Tcon-based haploidentical HSCT (Treg/Tcon haplo-HSCT) we used high dose hyper-fractionated TBI (HF-TBI) in the conditioning regimen. We also extended Treg/Tcon haplo-HSCT to patients that are unfit (because of previous comorbidities) and/or too old to withstand high intensity regimens. In these patients the extra-hematologic toxicity of irradiation was reduced with the use of targeted total marrow and lymph node irradiation (TMLI). 40 patients with high risk acute leukemia (36 AML, 4 ALL) received Treg/Tcon haplo-HSCT. All but 3 patients were transplanted in complete remission. 12 younger patients (median age: 28, range: 20-43) received HF-TBI, while 28 older or unfit patients (59, 40-70) received TMLI in the conditioning regimen. HF-TBI (14.4 Gy) was administered in 12 fractions, 3 times a day for 4 days. TMLI was administered by means of Helical Tomotherapy HI-ART (9 fractions, 2 times a day for 4.5 days). Irradiation was followed by chemotherapy with Thiotepa, Fludarabine, and Cyclophosphamide. 2 × 106/kg freshly isolated CD4+CD25+FOXP3+ Tregs were transferred 4 days before the infusion of 1 × 106/kg Tcons and a mega-dose of CD34+ hematopoietic stem cells. No post-transplant pharmacologic GvHD prophylaxis was given. 38/40 patients engrafted. 12 (31%) developed aGvHD grade ³2 (10 are alive and off-therapy). 6 (16%) died because of transplant related complications (2 because of aGvHD, 2 infections, 1 veno-occlusive disease, 1 intracranial hemorrhage). Strikingly, despite the high risk diseases, no patient relapsed after a median follow up of 13 months (range 1-36, Fig. A). Further, only 1 patient developed cGvHD. Thus, cGvHD/Leukemia-free survival was 82% (Fig. B). Treg adoptive transfer allows for the safe infusion of an otherwise lethal dose of donor alloreactive Tcons in the absence of any other form of immune suppression. Our results demonstrate that the potent graft versus leukemia effect of Treg/Tcon adoptive transfer was boosted by high dose marrow irradiation. Thus, this study proves that the right combination of haploidentical Treg/Tcon immunotherapy plus a powerful conditioning regimen can fully eradicate leukemia.

The Total Body Irradiation Schedule Affects Acute Leukemia Relapse After Matched T Cell–Depleted Hematopoietic Stem Cell Transplantation

We sought to determine whether the total body irradiation (TBI) schedule affected outcome in patients with acute leukemia in complete remission who received Tcell-depleted allogeneic hematopoietic stem cell transplantation from HLA identical siblings. The study recruited 55 patients (median age, 48years; age range, 20-66years; 30 men and 25 women; 34 with acute myeloid leukemia and 21 with acute lymphoid leukemia). Hyperfractionated TBI (HTBI) (1.2Gy thrice daily for 4days [for a total dose of 14.4Gy] from day -12 to day -9) was administered to 29 patients. Single-dose TBI (STBI) (8Gy, at a median dose rate of 10.7cGy/min on day -9) was given to 26 patients. All patients achieved primary, sustained engraftment with full donor-type chimerism. At 10years, the overall cumulative incidence of transplant-related mortality was 11% (SE, ±0.1%). It was 7% (SE, ±0.2%) after HTBI and 15% (SE, ±0.5%) after STBI (P=.3). The overall cumulative incidence of relapse was 33% (SE, ±0.5). It was 13% (SE, ±0.5%) after HTBI and 46% (SE, ±1%) after STBI (P=.02). The overall probability of disease-free survival (DFS) was 59% (SE, ±7%). It was 67% (SE, ±0.84%) after HTBI and 37% (SE, ±1.4%) after STBI (P=.01). Multivariate analyses showed the TBI schedule was the only risk factor that significantly affected relapse and DFS (P=.01 and P=.03, respectively). In patients with acute leukemia, HTBI is more efficacious than STBI in eradicating minimal residual disease after HLA-matched Tcell-depleted hematopoietic stem cell transplantation, thus affecting DFS.

Ex Vivo T Cell–Depleted versus Unmodified Allografts in Patients with Acute Myeloid Leukemia in First Complete Remission

This study was conducted to retrospectively compare the clinical outcomes after transplantation of T cell–depleted (TCD) and unmodified allografts in patients with acute myeloid leukemia (AML) in first complete remission (CR1). Patients received TCD grafts at Memorial Sloan-Kettering Cancer Center (MSKCC, N = 115) between 2001 and 2010 using the following preparative regimens: hyperfractionated total body irradiation (HFTBI)+thiotepa+fludarabine; HFTBI+thiotepa+cyclophosphamide; or i.v. busulfan+melphalan+fludarabine. TCD was performed by 1 of 2 immunomagnetic CD34+ cell selection methods for peripheral blood grafts or by soybean lectin agglutination followed by sheep red blood cell–rosette depletion for bone marrow grafts. No additional graft-versus-host disease (GVHD) prophylaxis was administered. Patients received unmodified grafts at M.D. Anderson Cancer Center (MDACC, N = 181) after conditioning with busulfan+fludarabine and GVHD prophylaxis with tacrolimus+mini-methotrexate. Patients with unrelated or human leukocyte antigen–mismatched donors received anti-thymocyte globulin (ATG) at both centers, with some recipients of matched related donor TCD transplants also receiving ATG, depending upon the preparative regimen. TCD graft recipients were more likely to be older, receive a mismatched transplant, and have peripheral blood used as the graft source. The incidences rates of grades 2 to 4 acute GVHD and chronic GVHD were significantly lower in the TCD graft group (5% versus 18%, and 13% versus 53%). Three-year relapse-free and overall survival rates were 58% and 57%, respectively, in recipients of TCD grafts, and 60% and 66% in recipients of unmodified grafts (P = not significant). Survival and relapse-free survival are similar after TCD and conventional transplants from related/unrelated donors in patients with AML in CR1, but TCD significantly reduces GVHD.

Ex-Vivo T Cell-Depleted Versus Unmodified Allografts in Patients with Acute Myeloid Leukemia in First Complete Remission: A Comparison of Outcomes in Two Institutions

Abstract 2013Allogeneic stem cell transplantation (ASCT) with T-cell depleted (TCD) allograft has been used to decrease the risk of graft-versus-host disease (GVHD). How outcomes of ASCT with TCD grafts compares to transplant with unmodified grafts in the context of ablative, reduced toxicity conditioning with busulfan /fludarabine is unknown. We sought to compare ASCT with and without TCD grafts, by studying the outcomes of pts with acute myeloid leukemia (AML) in first complete remission (CR1) who had TCD allografts at Memorial Sloan Kettering Cancer Center (MSKCC) with those who had unmodified allografts at MD Anderson Cancer Center (MDACC).Transplants at MSKCC (N=115) and MDACC (N=181) were performed between 2001 and 2010. Preparative regimens at MSKCC included: 1) Hyperfractionated total body irradiation (HFTBI) 1375 cGy over 4 days, thiotepa 5 mg/kg/day × 2 days & fludarabine 25 mg/m2/day × 5 days (n=29); 2) HFTBI 1375 cGy over 4 days, thiotepa 5 mg/kg/day × 2 days & cyclophosphamide 60 mg/kg/day × 2 days (n=25); or 3) busulfan 0.8 mg/kg intravenously every 6 hours for 10 doses(n=42) or 12 doses (n=19), melphalan 70 mg/m2/day × 2 days & fludarabine 25 mg/m2/day × 5 days (total n=61). Peripheral blood (PB) grafts underwent CD34+ cell selection using the ISOLEX 300i system, followed by sheep red blood cell (sRBC)-rosette depletion (n=85); or CD34+ cell selection using the CliniMACS system alone (n=22). Bone marrow (BM) grafts were T cell depleted by sequential soybean lectin agglutination and sRBC-rosette depletion (n=8). No additional GVHD prophylaxis was administered at MSKCC.Fludarabine 40 mg/m2 and busulfan 130 mg/m2 intravenously once daily for 4 days were used for conditioning at MDACC, with tacrolimus and mini-methotrexate for GVHD prophylaxis. Pts with unrelated or HLA-mismatched donors treated at MDACC and MSKCC received equine (total 60 mg/kg) or rabbit (total 2.5–5 mg/kg) anti-thymocyte globulin. Cytogenetic risk stratification considered complex cytogenetics, -5, -5q, -7, -7q, 11q23 aberrations, inv(3), t(3;3), t(6;9), and t(9;22) as poor risk.Pt characteristics and outcomes are summarized in the Table. TCD recipients were more likely to be older, receive a mismatch transplant, and have PBSC used as a graft source. Overall, only one pt, who had received an unmodified graft, experienced primary graft failure. Eleven (10%) and 33 (18%) pts experienced grade ≥2 acute GVHD within 100 days after transplants with TCD and unmodified grafts, respectively (p=0.05). Three-year relapse-free and overall survival rates were 58% and 57% in pts who received TCD grafts, and 60% and 66% in pts who received unmodified grafts (P=NS; Figure). There was a trend towards lower early non-relapse mortality among pts who received unmodified grafts (3% vs. 8% at 100 days, p=0.07). Of age, sex, secondary disease, risk status, donor, and graft type, secondary AML was the only risk factor found to significantly influence overall survival (HR: 1.7, 95% CI: 1.1–2.8). Survival outcomes were still comparable between recipients of TCD and unmodified grafts after adjusting for secondary AML. None of these factors significantly predicted relapse-free survival. Conclusion:Myeloablative ASCT with TCD or unmodified allografts lead to comparable outcomes in this high-risk cohort of AML pts in CR1 with a lower acute GVHD rate observed after TCD transplants.CharacteristicsFrequency, n (%)TCD, N=115Unmodified, N=181pTime CR1 to transplant, days*83 (12–304)97 (8–455)0.040Age, years*52 (19–71)48 (18–63)<0.001>50 years66 (57)76 (42)0.010Sex = Female58 (50)90 (50)NSEtiologyde novo60 (52)144 (80)<0.001Secondary38 (33)24 (13)Therapy-related17 (15)13 (7)Cytogenetic risk statusNSGood1 (1)2 (1)Intermediate72 (63)103 (57)Poor42 (37)76 (42)Donor typeMRD56 (49)103 (57)MUD32 (28)64 (35)MM27 (23)14 (8)<0.001Graft typeBM8 (7)57 (32)<0.001PB107 (93)124 (68)Outcome (95% CI)3-year RI18% (12%–27%)25% (19%–33%)NS100 day NRM8% (4%–15%)3% (1%–7%)0.071-year NRM18% (12%–27%)13% (9%–19%)NS3-year NRM24% (17%–34%)16% (11%–23%)NS3-year RFS58% (47%–67%)60% (51%–67%)NS3-year OS57% (47%–67%)66% (58%–74%)NSTCD: T-cell depleted, CR1: First complete remission, MRD: Matched related donor, MUD: Matched unrelated donor, MM: HLA-mismatch donor, BM: Bone marrow, PB: Peripheral blood, RI: Relapse incidence, NRM: Non-relapse mortality, RFS: Relapse-free survival, OS: Overall survival.*: Median (range). [Display omitted] Disclosures:No relevant conflicts of interest to declare.

Incidence, risk factors, and clinical outcomes of cataracts following hematopoietic stem cell transplantation

To evaluate the characteristics of cataracts following hematopoietic stem cell transplantation (HSCT), 561 patients without any ocular complications before HSCT were reviewed. Ocular complications occurred in 196 patients (34.9%). Cataract was diagnosed in 45 of 561 patients. The 10-year estimated cataract incidence was 14%. The median onset time was 498 days after transplant (range, 38-4,535 days). The onset of cataracts was later than that of other ocular complications. Phacoemulsification was performed in 13 patients (29%) at a median of 1,028 days after HSCT (range, 375-4,549 days). In 6 of 13 patients (46%) who underwent cataract surgery, visual acuities gradually deteriorated because of the development of posterior capsule opacification. YAG (yttrium-aluminum-garnet) laser posterior capsulotomy successfully recovered their sight without any sequelae. A multivariate analysis revealed that age, acute and chronic graft versus host disease (GVHD), and systemic infection were significant risk factors for cataract, whereas neither steroid nor total body irradiation (TBI)-containing regimens affected the development of cataract. Our results showed that the clinical outcomes of cataract after HSCT are favorable and comparable to those in the general population. Hyperfractionated TBI with eye shielding may be effective for the prevention of cataract.

Allogeneic Hematopoietic Stem Cell Transplantation (HSCT) for the Treatment of Children with Very High Risk (VHR) Acute Lymphoblastic Leukemia (ALL) In First Remission (CR1)

AbstractAbstract 3546Between August 1988 and December 2009, 40 pediatric patients (pts) received an allogeneic HSCT for the treatment of very high risk ALL in CR1. They were 22 males and 18 females, aged 0.8 –19.2 years (median 10.0). Thirty eight patients had very high risk features: high white cell count greater than 200,000/mm3 (N=7), hypodiploidy (N=6), including double hypodiploidy (N=3), high risk cytogenetics with t(9;22) (N=14) or Mixed Lineage Leukemia (MLL) (N=3), and induction failure (N=23). Induction failure was defined morphologically by a single marrow aspirate revealing greater than 35% blasts by day +7 of induction, or greater than 5% blasts by day +14 or day +28 of induction. The remaining two patients included one infant ALL with a WBC >100,000/mm3 and one patient with ALL, Evans Syndrome and a prior CNS hemorrhage and fungal infection. Twenty two patients had one VHR feature while 16 patients had two VHR features. Patients received marrow or peripheral blood stem cell transplants from HLA-matched siblings (N=14) or volunteer unrelated donors (N=21) or unrelated double cord blood transplants (N=5). Unrelated donors were HLA-matched for 12 pts, but mismatched for nine pts at one (N=6) or two Class I antigens (N=3). All cord blood donors were matched at 4 or 5/6 HLA-antigens. Twenty three patients received T-cell depleted grafts following cytoreduction with hyperfractionated total body irradiation (HF-TBI) 1,375-1,500 cGy, Thiotepa (Thio) 5 mg/Kg/day × 2 and Cyclophosphamide (CY) 60 mg/Kg/day × 2. Grafts were marrow T-cell depleted with soy bean agglutinin and e-rosetting for 15 patients or peripheral blood stem cells T-cell depleted by CD34 selection and E-rosetting for 8 patients. Twelve pts received unmodified grafts following cytoreduction with a TBI-CY based regimen (N=8) or chemotherapy regimen (N=4). Five patients received double cord blood grafts following HF-TBI 1,375 cGY, Fludarabine 25 mg/m2/day × 3 and CY 60 mg/Kg/day × 2. Graft-versus-host disease (GvHD) prophylaxis for the BMT recipients included cyclosporine (CSA) + methotrexate or steroids, and for the cord blood recipients, CSA and mycophenolate mofetil.With a median follow-up of 11.1 years (range 0.6–21.9 yrs), the 10-year overall survival and disease-free survival of the entire cohort were 78% and 70% respectively, and 80% and 72% respectively when excluding the accidental death. Two recipients of T-cell depleted grafts suffered a graft failure (one early and one late), both of whom received a secondary T-cell depleted graft from a (different) mismatched related donor, engrafted and are alive and well. Two recipients of unmodified marrow grafts relapsed 4.9, and 18.9 months post BMT, one of whom is still alive disease free following treatment with chemotherapy. One recipient of a double cord blood graft relapsed three months post transplant. The overall risk of relapse for the entire cohort was 15%. Six pts died; cause of death was: relapse (N=2), secondary malignancy (N=2), acute GvHD (N=1), and accidental death (head trauma) (N=1). Grade 2–4 GvHD was diagnosed in recipients of unmodified grafts (N=3), double cord blood graft (N=2) and T-cell depleted grafts (N=1). The OS and DFS for recipients of T-cell depleted transplants following TBI THIO CY were both 83% with a 0% relapse rate.In summary, the outcome of allogeneic HSCT for children with very high risk ALL in CR1 in our series appears to be superior to that reported with chemotherapy for patients with these very high risk features. Moreover, the use of hyperfractionated TBI, Thio and CY followed by T-cell depleted grafts from related or unrelated donors was associated with a very good outcome with no relapse and minimal GvHD. Disclosures:No relevant conflicts of interest to declare.

Matched Unrelated Donor Allogeneic Stem Cell Transplantation in High Risk Acute Lymphoblastic Leukemia (ALL) After a Preparative Regimen of Hyperfractionated Total Body Irradiation and High-Dose Etoposide – A Feasibility Study within the German Multicenter Study Group for Adult ALL.

Abstract 3389Poster Board III-277 Introduction:The optimal preparative regimen for allogeneic hematopoietic stem cell transplantation (alloHCT) using matched unrelated donors (MUD) for adult patients (pts) with acute lymphoblastic leukemia (ALL) in first complete remission (CR1) is currently undefined. There is some evidence from one comprehensive retrospective comparative analysis that a higher dose of hyperfractionated total body irradiation (fTBI) or the use of high-dose etoposide instead of cyclophosphamide is able to reduce the leukemic relapse risk of adult pts transplanted in second CR from HLA-identical sibling donors (ISD) (Marks, DI et al. J Biol Blood Marrow Transplant 12: 438-453, 2006). Purpose:Within the framework of the German multicenter study group for adult ALL (GMALL) protocols 06/1999 and 07/2003, the combination of 12 Gy fTBI + 120 mg/kg cyclophosphamide is the standard preparative regimen for MUD alloHCT in CR1. In these protocols, a preparative regimen of 12 Gy fTBI + 60 mg/kg etoposide before ISD alloHCT in CR1 has shown particular promising results compared to 12 Gy fTBI + cyclophosphamide. Therefore, this pilot study tested the feasibility of the12 Gy fTBI + etoposide regimen for MUD alloHCT in CR1 adult ALL pts. Patients and methods:In the GMALL protocol 07/2003, alloHCT is generally performed after the first consolidation therapy according to predefined prognostic disease features indicating a high relapse risk for pts up to the age of 55 years (yrs). This study prospectively included 20 consecutive (very) high-risk pts (median age: 39 [range 17 to 55] yrs) from two major GMALL transplant centers, who underwent alloHCT using MUD between 01/07 and 03/09. TBI was applied in 2 daily fractions of 2 Gy on 3 consecutive days (days -6 to -4) followed by etoposide on day -3 (alloHCT on day 0). For prophylaxis of acute graft-versus-host disease (GvHD), 3 × 20 mg/kg antithymocyte globuline was given on days -3 to -1 and ciclosporin combined with prednisone thereafter. Results:Neutrophil reconstitution > 0.5/nL was reached after a median of 18 (range 12 to 32) days and self-sustaining platelet counts > 20/nL were attained after a median of 25 (range 13 to 36) days. The cumulative incidence of grades I – IV acute GvHD reached 64 %. Three pts. (15 %) developed acute GvHD > grade II. The cause-specific non-relapse mortality (NRM) incidences at 3, 12 and 24 months are 5 %, 18 %, and 22 % (4/20 pts), respectively. Causes of NRM were infections (2 pts), graft failure and toxic epidermiolysis (1 patient each). The cause-specific leukemic relapse incidence reaches 18 % (3/20 pts) after 12 and 24 months. Two pts were successfully rescued by a 2nd alloHCT after leukemic relapse. After a median follow-up period of 22 months for the 15 surviving pts, the 2-year overall survival estimate is 73 % (95 % confidence limits: 47 % - 89 %). Conclusions:This pilot study demonstrates that the preparative regimen of fTBI + etoposide before MUD alloHCT is feasible in CR1 adult high-risk ALL pts after intensive induction and consolidation courses as applied in the GMALL protocol 07/2003. The comparatively low relapse rate in high-risk ALL pts further supports that the substitution of cyclophosphamide by etoposide leads to better disease control and may thereby improve transplant outcome in this setting. Based on these results, a prospective study comparing fTBI in combination with either etoposide or cyclophosphamide appears justified. Disclosures:No relevant conflicts of interest to declare.

T cell–depleted stem-cell transplantation for adults with hematologic malignancies: sustained engraftment of HLA-matched related donor grafts without the use of antithymocyte globulin

Antithymocyte globulin (ATG) has been used in allogeneic stem-cell transplantation to prevent graft rejection and graft-versus-host disease (GvHD). Its use, however, has been associated with delayed T-cell reconstitution and prolonged susceptibility to opportunistic infections (OIs) especially in patients undergoing T cell-depleted (TCD) transplantation. Recently, a prospective trial was conducted in 52 adult patients (median age, 47 years) with various hematologic malignancies undergoing TCD transplantation from HLA-matched related donors without the use of ATG. The cytoreductive regimen consisted of hyperfractionated total body irradiation (HFTBI), thiotepa, and fludarabine. The preferred source of the graft was peripheral blood stem cells (PBSCs). No additional graft rejection or GvHD prophylaxis was given. All evaluable patients engrafted without any immune-mediated graft rejections. Disease-free survival (DFS) at 3 years was 61% in all patients, and 70% in patients with standard-risk disease. Acute GvHD was limited to grade 2 in 8% and chronic GvHD in 9% of patients. Life-threatening OIs occurred in 3 of 52 patients and was fatal in 1. This study demonstrates durable engraftment with a low incidence of GvHD despite the lack of ATG, as well as the curative potential of this regimen.

Final height in pediatric patients after hyperfractionated total body irradiation and stem cell transplantation

Impaired linear growth has been shown to occur in individuals treated during childhood with single-dose and fractionated total body irradiation (TBI) before stem cell transplantation. Our objective was to describe the final heights attained and patient/treatment factors correlating with final height in a cohort of childhood cancer survivors treated with hyperfractionated TBI (total dose 1375 or 1500 cGy). Thirty individuals (18 men) were included in the study. The mean final height standard deviation score (s.d.s.) was -1.9 +/- 0.2, significantly lower than height s.d.s. at TBI (-0.2 +/- 0.2, P < 0.001). Final height s.d.s. was significantly correlated with age at diagnosis, age at TBI and target height (P = 0.04, P < 0.001, P < 0.001, respectively). Treatment with growth hormone (GH) (n = 7) maintained mean height s.d.s. at -2.0 from the onset of GH therapy until attainment of final height. The mean final sitting height s.d.s. was -2.2 +/- 0.2 (n = 16), significantly shorter than mean final standing height s.d.s. (P < 0.01). In conclusion, treatment with hyperfractionated TBI is associated with a reduction in standing height and an even greater reduction in sitting height. Final height after hyperfractionated TBI was similar to that reported after fractionated TBI.

Results of T Cell Depleted (TCD) Allogeneic Hematopoietic Stem Cell Transplantation (AlloHSCT) from HLA Matched (HLA-M) or Partially Mismatched (HLA-MM) Unrelated Donors (URD) in Patients with Hematologic Malignancies: Sustained Engraftment and Low Incidence of Graft-vs-Host Disease (GvHD).

Curative strategies for hematologic malignancies include alloHSCT, which has become a treatment option for older pts, as well as those with more extensive prior therapy and comorbidities. This has stimulated research on the development of less toxic but comparably effective approaches to transplantation at the level of cytoreduction, alternate graft sources, graft manipulation, and GvHD prophylaxis. To this end, between 7/2001 and 12/2005, we administered TCD HSCTs, derived from HLA-M or HLA-MM URDs, to 36 adult pts as treatment for a variety of hematologic malignancies on a clinical trial. The conditioning regimen was designed to reduce regimen related toxicity while preserving adequate immunosuppression to allow for engraftment. The TCD grafts allowed transplantation across HLA disparate pt-donor pairs without the use of additional renal and hepatotoxic GvHD prophylaxis. The conditioning regimen consisted of hyperfractionated total body irradiation (HFTBI) (1375 cGy), thiotepa (5mg/kg) x 2d, fludarabine (25mg/m2) x 5d and antithymocyte globulin (ATG) x 2d. HLA typing was performed by DNA SSOP analyses for A,B,C, DRB1, and DQB1, and donors were matched at ≥8 of 10 alleles. Pts received TCD-PBSC (n=29) or TCD-BM (n=7) from HLA-M (21 pairs) or HLA-MM (15 pairs) URDs. PBSCs were TCD by Isolex 300i CD34+ selection followed by sheep E-rosette depletion, and BMs were depleted with soybean agglutination and sheep E-rosette depletion. The median age was 40.6 (range 18–63)yrs; 10 pts ≥ 50 yrs. Diseases included AML and ALL CR1 (only standard or high risk), AML and ALL CR2, ALL ≥ CR3, acute biphenotypic leukemia, CML in CP, MDS, T-PLL. The median followup is 22 (range 6–55) mos. All evaluable pts engrafted neutrophils, 31 of 35 evaluable pts engrafted platelets. Four pts died of complications prior to platelet engraftment, including one pt with late graft failure. The 100d non-relapse mortality was 20% with most (>50%) deaths due to infection. The incidence of acute (a) grade II–III and chronic (c) GvHD was low for the entire group of 36 pts at 11% and 28%, respectively, when compared to that of unmodified transplantation. The incidence of aGvHD was 14% and 7%, and cGvHD (majority - limited) was 26% and 30% for HLA-M and HLA-MM transplant pairs, respectively. Estimated 3 yr DFS is 60% for both HLA-M and HLA-MM transplants, and 83% for standard risk and 41% for high risk disease pts. Only one pt has relapsed. These results indicate that a transplantation strategy using HFTBI, thiotepa, fludarabine and ATG followed by TCD PBSC or BM, but without posttransplant immunomodulating agents, is well-tolerated in an older patient group (median age 40 yrs) even with HLA-MM URDs. Although this approach appears to provide an antileukemic effect for acute leukemia pts transplanted in remission of acute leukemia, this will need to be confirmed with longer followup.

Prospective evaluation of delayed central nervous system (CNS) toxicity of hyperfractionated total body irradiation (TBI)

Purpose: Prospective evaluation of chronic radiation effects on the healthy adult brain using neuropsychological testing of intelligence, attention, and memory. Methods and Materials: 58 patients (43 ± 10 yr) undergoing hyperfractionated total body irradiation (TBI) (TBI, 14.4 Gy, 12 × 1.2 Gy in 4 days) before bone marrow or peripheral blood stem cell transplantation were prospectively included. Twenty-one recurrence-free long-term survivors were re-examined 6–36 months (median 27 months) after completion of TBI. Neuropsychological testing included assessment of general intelligence, attention, and memory using normative, standardized psychometric tests. Mood status was controlled, as well. Test results are given as IQ scores (population mean 100) or percentiles for attention and memory (population mean 50). Results: The 21 patients showed normal baseline test results of IQ (101 ± 13) and attention (53 ± 28), with memory test scores below average (35 ± 21). Test results of IQ (98 ± 17), attention (58 ± 27), and memory (43 ± 28) showed no signs of clinically measurable radiation damage to higher CNS (central nervous system) functions during the follow-up. The mood status was improved. Conclusion: The investigation of CNS toxicity after hyperfractionated TBI showed no deterioration of test results in adult recurrence-free patients with tumor-free CNS. The median follow-up of 27 months will be extended.

Autologous stem cell transplantation (ASCT) with immunologically purged progenitor cells in patients with advanced stage follicular lymphoma after early partial or complete remission: toxicity, follow-up of minimal residual disease and survival.

The role of autologous stem cell transplant (ASCT) in indolent lymphomas is a controversial issue. From 1994 to 1999, we performed ASCT with immunologically purged progenitor cells in 15 patients with advanced stage follicular lymphoma (FL) after early partial or complete remission. Results of the purging strategy and follow-up of minimal residual disease after transplant were analyzed with PCR amplification of bcl-2/IgH rearrangement for the t(14;18) translocation. A comparison of transplanted patients with a group of controls was carried out to evaluate differences in progression-free survival and overall survival. Eighty percent of patients received one chemotherapy regimen before ASCT and were in first remission. All the patients received cyclophosphamide plus hyperfractionated total body irradiation as the conditioning regimen. Nine patients were transplanted with bone marrow (BM) and six with peripheral blood progenitor cells (PBPC). Engraftment was delayed in one patient transplanted with BM. Two patients died during the transplant procedure. Ten of 12 evaluable patients were PCR positive in the BM for bcl-2 rearrangement at diagnosis. Six of them (60%) were still positive after chemotherapy, and one patient was transplanted with a positive hematopoietic product after purging. With a median follow-up of 27 months, six of eight evaluable patients still remain PCR negative in the BM. With a median follow-up of 4.7 years from diagnosis, progression-free survival was 83% (95% CI: 63-100). The risk of disease progression of non-transplanted patients was 19.2 times higher than that of transplanted patients (P = 0.01), but no differences were found in overall survival. Regarding patients in first remission, the risk of relapse was 12.6 times higher in non-transplanted than in transplanted patients (P = 0.04). This procedure seems to offer a good chance to achieve a PCR-negative state and prolonged freedom from recurrence. According to these results, prospective randomized trials are warranted.

Neurobehavioral toxicity of total body irradiation: a follow-up in long-term survivors

Purpose: Total body irradiation (TBI) in preparation for bone marrow transplantation (BMT) is a routine treatment of hematological malignancy. A retrospective and a prospective group study of long-term cerebral side effects was performed, with a special emphasis on neurobehavioral toxicity effects. Methods and Materials: Twenty disease-free patients treated with hyperfractionated TBI (14.4 Gy, 12 × 1.2 Gy, 4 days), 50 mg/kg cyclophosphamide, and autologous BMT (mean age 38 years, range 17–52 years; age at TBI 35 years, 16–50 years; follow-up time 32 months, 9–65 months) participated in a neuropsychological, neuroradiological, and neurological examination. Data were compared to 14 patients who were investigated prior to TBI. Eleven patients with renal insufficiencies matched for sex and age (38 years, 20–52 years) served as controls. In a longitudinal approach, neuropsychological follow-up data were assessed in 12 long-term survivors (45 years, 23–59 years; follow-up time 8.8 years, 7–10.8 years; time since diagnosis 10.1 years, 7.5–14.2 years). Results: No evidence of neurological deficits was found in post-TBI patients except one case of peripheral movement disorder of unknown origin. Some patients showed moderate brain atrophy. Neuropsychological assessment showed a subtle reduction of memory performance of about one standard deviation. Cognitive decline in individual patients appeared to be associated with pretreatment (brain irradiation, intrathecal methotrexate). Ten-years post disease onset, survivors without pretreatment showed behavioral improvement up to the premorbid level. Conclusion: The incidence of long-term neurobehavioral toxicity was very low for the present TBI/BMT regimen.

Cataract incidence after total-body irradiation

Purpose: The aim of this retrospective study was to evaluate cataract incidence in a homogeneously-treated group of patients after total-body irradiation (TBI) followed by autologous bone marrow transplantation or peripheral blood stem cell transplantation. Methods and Materials: Between 1982 and 1994, a total of 260 patients received either autologous bone marrow or blood stem cell transplantation for hematological malignancy at the University of Heidelberg. Two hundred nine of these patients received TBI in our hospital. Radiotherapy was applied as hyperfractionated TBI, with a median dose of 14.4 Gy in 12 fractions over 4 days. Minimum time between fractions was 4 h. Photons with an energy of 23 MeV were used with a dose rate of 7–18 cGy/min. Ninety-six of the 209 irradiated patients were still alive in 1996; 86 of these patients (52 men, 33 women) answered a questionnaire and could be examined ophthalmologically. The median age at time of TBI was 38.5 years, with a range of 15–59 years. Results: The median follow-up is now 5.8 years, with a range of 1.7–13 years. Cataract occurred in 28/85 patients (32.9%) after a median of 47 months (1–104 months). In 6 of 28 patients who developed a cataract, surgery of the cataract was performed. Whole-brain irradiation prior to TBI had been performed more often in the group of patients developing cataract (14.3%) versus 10.7% in the group of patients without cataract. However, there was no statistical difference (Chi-square, p > 0.05). Conclusion: Cataract is a common side effect of TBI. Cataract incidence found in our patients is comparable to results of other centers using a fractionated regimen for TBI. To assess the incidence of cataract after TBI, a long-term follow-up is required.

Lethal pulmonary toxicity after autologous bone marrow transplantation/peripheral blood stem cell transplantation for hematological malignancies

Background and purpose: Retrospective evaluation of the incidence of lethal pulmonary complications (LPC) with special emphasis on interstitial pneumonia (IP) in a large group of patients homogeneously treated with hyperfractionated total body irradiation (HTBI) before autologous bone marrow transplantation (ABMT) or peripheral blood stem cell transplantation (PBSCT) for hematological malignancy. The factors influencing IP are discussed. Materials and methods: Of 260 patients (maximum follow-up 137 months) that were treated with ABMT or PBSCT for hematological neoplasms between 1982 and 1994, 209 patients received HTBI and could be evaluated with respect to lethal pulmonary complications and especially lethal interstitial pneumonia. For most patients ( n=155), the HTBI dose was 14.4 Gy (lung dose 9–9.5 Gy) given in 12 fractions over 4 days. Twenty-one patients received a total dose of ≥15 Gy with pulmonary doses of 9–10.5 Gy. Results: The actuarial overall 5-year survival for all 209 patients evaluated was 44±4%, enabling valid evaluation with respect to lethal pulmonary toxicity. The actuarial incidence of all LPC during the first year was calculated as being 8±2%. The actuarial incidence of lethal IP is certainly lower and was estimated to be between 3 and 5% for all patients. The overall treatment-related mortality was 12% in 188 patients that received a total dose of <15 Gy and 24% among the patients treated with a total dose of ≥15 Gy. Conclusion: ABMT/PBSCT, like other transplant modalities without significant graft versus host disease (GvHD), has a low transplant-related mortality, a very small rate of overall LPC and a low incidence of lethal IP after HTBI. Doses up to 14.4 Gy with lung doses of 9–9.5 Gy can be administered safely. For total doses of ≥15 Gy with lung doses of 9–10.5 Gy, the risk of serious transplant-related complications cannot yet be finally assessed but such higher doses should be considered with caution because of the possibility of increasing toxicity in organs other than the lung.

A comparison of single-dose and fractionted total-body irradiation on the development of pneumonitis following bone marrow transplantation

Purpose : A review of 132 consecutive patients who received bone marrow transplant for various malignancies was conducted to determine factors associated with increased risk in developing interstitial pneumonitis (IP) as the result of total body irradiation (TBI). Twenty-four patients were excluded because 22 did not receive TBI and two had insufficient records. Methods and Materials : Patients were conditioned with TBI and various drug regimens. Eighteen patients received a single 6.0 Gy dose of x-rays. The remaining 90 were treated with three doses of 3.33 Gy separated by 24 h. All patients were followed for at least 18 months for the purposes of determining the IP incidence. Results : Twenty-seven of these 108 (25%) patients developed IP; 19 (17.6%) died. The 2-year estimated incidence of IP was 24 and 18.6% for fatal IP. The etiology was determined to be idiopathic in 12 patients, the result of cytomegalovirus in 6 patients, and caused by a variety of other infectious organisms in 9 patients. We were unable to demonstrate a statistically significant increase in IP with age (adults vs. children), dose regimen, use of methotrexate for graft-vs.-host disease prophylaxis, the presence of acute graft-vs.-host disease, time from diagnosis to transplant, or transplant type (allogeneic vs. autologous). Conclusions : The incidence of fatal IP reported here is similar to that reported by other institutions utilizing hyperfractionated TBI protocols. Our data do not support the need for hyperfractionation to reduce the risk of IP.

59 O - Thiotepa improves results of t-cell-depleted bone marrow tranplants for acute leukemia. a seven year experience

T cell-depletion of the donor bone marrow prevents GvHD in matched BMT recipients, but this benefit is offset by an increased risk of graft failure and leukemia relapse. One approach 10 improving disease-free survival of TCD transplants recipients is to employ intensified conditioning regimens. More intensive pre-transplant immunosuppression and myeloablation should compensate for the loss of the anti-host and anti-leukemic effect, mediated by donor T cells and thereby overcome resistance to engraftment and provide a greater anti-leukemic activity. To this end, we desisned in 1989, a new conditioning regimen that added ATG and thiotepa (IT) to Cy and 1440 cGy hyperfractionated TBI, to enhance both immunosuppression and myeloablation. From June 1989, 54 patients (33 M, 21 F; median age 29 years, range 6–53) with acute leukemia (30 AML, 24 ALL) in hematological remission (22 CR L 14 CR II) or relapse (N = 18) received HLA-identical BMI depleted of T cells by the soybean agglutinin and E-rosetting technique. No additional post-transplant immunosuppressive treatment was given. All patients engrafted with a full-donor type chimerism. Neither acute nor chronic GvHD occurred in any evaluable patient of the 36 patients in remission at transplant, 24, survive event-tree at a median follow-up of 50 months (range 26.78) with a PS 100%. 6 relapsed (2AML, 4 ALL) and 6 died from TRM Of the 18 in relapse at transplant, 4 survive event-free at a median follow-up of 44 months (range 30–46), 7 relapsed (2AML.5ALL) and 6 died from TRM. We believe that TT enhances the cytoreductive elfect of the conventional conditioning regimens in T-depleted BMTs and that there is a GvL effect mediated by the expansion of immunocompetent lymphocytes in the absence of GvHD when no cyclosporine is given.

2045 Incidence of interstitial pneumonia after hyperfractionated total body irradiation before autologous bone marrow/stem cell transplantation

2045 Incidence of interstitial pneumonia after hyperfractionated total body irradiation before autologous bone marrow/stem cell transplantation

Myeloablative radiochemotherapy and hematopoietic stem-cell rescue in poor-prognosis Ewing's sarcoma.

The prognosis of patients with multifocal primary and early or multiple relapsed Ewing's sarcoma is poor with conventional chemoradiotherapy and surgery. We evaluated the efficacy and feasibility of a myeloablative regimen administered as consolidation treatment for these patients. The ablative regimens consisted of simultaneous radiochemotherapy: 12 Gy hyperfractionated total-body irradiation (TBI; two doses of 1.5 Gy for 4 days) plus fractionated high-dose melphalan (30 to 45 mg/m2 for 4 days) followed by high-dose etoposide (40 to 60 mg/kg) with or without carboplatin (900 to 1,500 mg/m2) (hyper-ME +/- C). These regimens were applied in a dose-escalation study that included 17 patients. All patients underwent remission induction chemotherapy and local treatment before myeloablative therapy. Seven patients had multifocal primary Ewing's sarcoma, and 10 had early or multiple relapse. We performed a matched-cohort analysis of the 17 grafted patients with 41 historic controls matched for sex, age, diagnosis, extent of disease, interval from diagnosis to transplant in the transplant group, and interval from diagnosis to relapse in the control group. The probability of relapse in the study patients is 52% at 6 years after the last event before transplantation. In the control group, the probability of relapse at 6 years was 98%. Eight of 17 treated patients are alive in complete remission at a median observation time of 49 months (range, 19 to 76) from the last event before transplantation. Probability of relapse-free survival in the study patients is 45% +/- 12% at 6 years after the last event before transplant, compared with 2% +/- 2% for the historic control group. Myeloblative therapy with hyper-ME +/- C radiochemotherapy can improve the prognosis of multifocal primary and early or multiple relapsing Ewing's sarcoma.