Allogeneic marrow transplantation using fractionated total body irradiation in patients with acute lymphoblastic leukemia in relapse

ESTRO ACROP and SIOPE recommendations for myeloablative Total Body Irradiation in children

BACKGROUND AND PURPOSE

Myeloablative Total Body Irradiation (TBI) is an important modality in conditioning for allogeneic hematopoietic stem cell transplantation (HSCT), especially in children with high-risk acute lymphoblastic leukemia (ALL). TBI practices are heterogeneous and institution-specific. Since TBI is associated with multiple late adverse effects, recommendations may help to standardize practices and improve the outcome versus toxicity ratio for children.

MATERIAL AND METHODS

The European Society for Paediatric Oncology (SIOPE) Radiotherapy TBI Working Group together with ESTRO experts conducted a literature search and evaluation regarding myeloablative TBI techniques and toxicities in children. Findings were discussed in bimonthly virtual meetings and consensus recommendations were established.

RESULTS

Myeloablative TBI in HSCT conditioning is mostly performed for high-risk ALL patients or patients with recurring hematologic malignancies. TBI is discouraged in children <3-4 years old because of increased toxicity risk. Publications regarding TBI are mostly retrospective studies with level III-IV evidence. Preferential TBI dose in children is 12-14.4 Gy in 1.6-2 Gy fractions b.i.d. Dose reduction should be considered for the lungs to <8 Gy, for the kidneys to ≤10 Gy, and for the lenses to <12 Gy, for dose rates ≥6 cGy/min. Highly conformal techniques i.e. TomoTherapy and VMAT TBI or Total Marrow (and/or Lymphoid) Irradiation as implemented in several centers, improve dose homogeneity and organ sparing, and should be evaluated in studies.

CONCLUSIONS

These ESTRO ACROP SIOPE recommendations provide expert consensus for conventional and highly conformal myeloablative TBI in children, as well as a supporting literature overview of TBI techniques and toxicities.

Total Body Irradiation in Haematopoietic Stem Cell Transplantation for Paediatric Acute Lymphoblastic Leukaemia: Review of the Literature and Future Directions

Total body irradiation (TBI) has been a pivotal component of the conditioning regimen for allogeneic myeloablative haematopoietic stem cell transplantation (HSCT) in very-high-risk acute lymphoblastic leukaemia (ALL) for decades, especially in children and young adults. The myeloablative conditioning regimen has two aims: (1) to eradicate leukaemic cells, and (2) to prevent rejection of the graft through suppression of the recipient's immune system. Radiotherapy has the advantage of achieving an adequate dose effect in sanctuary sites and in areas with poor blood supply. However, radiotherapy is subject to radiobiological trade-offs between ALL cell destruction, immune and haematopoietic stem cell survival, and various adverse effects in normal tissue. To diminish toxicity, a shift from single-fraction to fractionated TBI has taken place. However, HSCT and TBI are still associated with multiple late sequelae, leaving room for improvement. This review discusses the past developments of TBI and considerations for dose, fractionation and dose-rate, as well as issues regarding TBI setup performance, limitations and possibilities for improvement. TBI is typically delivered using conventional irradiation techniques and centres have locally developed heterogeneous treatment methods and ways to achieve reduced doses in several organs. There are, however, limitations in options to shield organs at risk without compromising the anti-leukaemic and immunosuppressive effects of conventional TBI. Technological improvements in radiotherapy planning and delivery with highly conformal TBI or total marrow irradiation (TMI), and total marrow and lymphoid irradiation (TMLI) have opened the way to investigate the potential reduction of radiotherapy-related toxicities without jeopardising efficacy. The demonstration of the superiority of TBI compared with chemotherapy-only conditioning regimens for event-free and overall survival in the randomised For Omitting Radiation Under Majority age (FORUM) trial in children with high-risk ALL makes exploration of the optimal use of TBI delivery mandatory. Standardisation and comprehensive reporting of conventional TBI techniques as well as cooperation between radiotherapy centres may help to increase the ratio between treatment outcomes and toxicity, and future studies must determine potential added benefit of innovative conformal techniques to ultimately improve quality of life for paediatric ALL patients receiving TBI-conditioned HSCT.

Pulmonary Toxicity After Total Body Irradiation - Critical Review of the Literature and Recommendations for Toxicity Reporting

INTRODUCTION

Total body irradiation is an effective conditioning regimen for allogeneic stem cell transplantation in pediatric and adult patients with high risk or relapsed/refractory leukemia. The most common adverse effect is pulmonary toxicity including idiopathic pneumonia syndrome (IPS). As centers adopt more advanced treatment planning techniques for TBI, total marrow irradiation (TMI), or total marrow and lymphoid irradiation (TMLI) there is a greater need to understand treatment-related risks for IPS for patients treated with conventional TBI. However, definitions of IPS as well as risk factors for IPS remain poorly characterized. In this study, we perform a critical review to further evaluate the literature describing pulmonary outcomes after TBI.

MATERIALS AND METHODS

A search of publications from 1960-2020 was undertaken in PubMed, Embase, and Cochrane Library. Search terms included "total body irradiation", "whole body radiation", "radiation pneumonias", "interstitial pneumonia", and "bone marrow transplantation". Demographic and treatment-related data was abstracted and evidence quality supporting risk factors for pulmonary toxicity was evaluated.

RESULTS

Of an initial 119,686 publications, 118 met inclusion criteria. Forty-six (39%) studies included a definition for pulmonary toxicity. A grading scale was provided in 20 studies (17%). In 42% of studies the lungs were shielded to a set mean dose of 800cGy. Fourteen (12%) reported toxicity outcomes by patient age. Reported pulmonary toxicity ranged from 0-71% of patients treated with TBI, and IPS ranged from 1-60%. The most common risk factors for IPS were receipt of a TBI containing regimen, increasing dose rate, and lack of pulmonary shielding. Four studies found an increasing risk of pulmonary toxicity with increasing age.

CONCLUSIONS

Definitions of IPS as well as demographic and treatment-related risk factors remain poorly characterized in the literature. We recommend routine adoption of the diagnostic workup and the definition of IPS proposed by the American Thoracic Society. Additional study is required to determine differences in clinical and treatment-related risk between pediatric and adult patients. Further study using 3D treatment planning is warranted to enhance dosimetric precision and correlation of dose volume histograms with toxicities.

Extramedullary sites of leukemia relapse after transplant

Recurrent or residual leukemia found in extramedullary sites after intensive treatments adversely affects prognosis. To summarize the sites and outcomes when extramedullary relapses have been reported after stem cell transplants, and to elucidate when long survival has been achieved, 207 cases were analysed. Authors were contacted for follow-up information. The most commonly reported sites are soft tissue in acute leukemias and bone in CML. Extramedullary relapse occurred typically within 2 years in ALL, but later in one-third of myeloid leukemias. Most testicular relapses reported in AML followed non-TBI conditioning. Marrow relapse was not inevitable if aggressive treatment was begun early. Local therapy alone was generally inadequate. Intensive therapy has produced lengthy remissions in cases of acute leukemias involving various sites, whereas CML cases, particularly involving bone, were most resistant to treatment. Heightened awareness and aggressive treatment should improve the prospect for cure after extramedullary relapse.

Clinical and economic comparison of allogeneic peripheral blood progenitor cell and bone marrow transplantation for acute lymphoblastic leukemia in children

There is limited experience in the use of peripheral blood progenitor cells (PBPC) for allogeneic transplantation in children. In the present study we compared engraftment kinetics, incidence of acute and chronic graft-versus-host disease (GVHD) and the outcome and economic costs of allogeneic PBPCT vs BMT in children with ALL in a single institution. All children were transplanted in complete remission (CR) with a similar conditioning regimen and the same GVHD prophylaxis. Patients undergoing PBPCT achieved myeloid and platelet engraftment before patients undergoing BMT (P < 0.001). Platelet recovery was faster for the PBPCT group (P < 0.014 for 50 x 10(9)/l and P < 0.039 for 100 x 10(9)/l). Incidence and severity of acute and chronic GVHD were similar in both groups (acute grade 1-2: 9/13 for PBPCT vs 9/11 for BMT; chronic GVHD: 5/12 for PBPCT vs 3/8 for BMT). Hospital stay was shorter for the PBPCT than for the BMT group (28.8 days vs 42.9 days, respectively) and the PBPCT group used less clinical resources, resulting in overall lower cost for PBPCT (US $14,046) compared to BMT (US $19,840). There was no statistically significant difference in DFS between PBPCT and BMT (68.4% vs 50%, respectively).

Total body irradiation correlates with chronic graft versus host disease and affects prognosis of patients with acute lymphoblastic leukemia receiving an HLA identical allogeneic bone marrow transplant

PURPOSE

To investigate whether different procedure variables involved in the delivery of fractionated total body irradiation (TBI) impact on prognosis of patients affected by acute lymphoblastic leukemia (ALL) receiving allogeneic bone marrow transplant (BMT).

METHODS AND MATERIALS

Ninety-three consecutive patients with ALL receiving a human leukocyte antigen (HLA) identical allogeneic BMT between 1 August 1983 and 30 September 1995 were conditioned with the same protocol consisting of cyclophosphamide and fractionated TBI. The planned total dose of TBI was 12 Gy (2 Gy, twice a day for 3 days). Along the 12-year period, variations in delivering TBI schedule occurred with regard to used radiation source, instantaneous dose rate, technical setting, and actual total dose received by the patient. We tested these different TBI variables as well as factors related to patient, state of disease, and transplant-induced disease to investigate their influence on transplant-related mortality, leukemia relapse, and survival.

RESULTS

At median follow-up of 7 years (range 3-15 years) the probabilities of leukemia-free survival (LFS) and overall survival (OS) for the 93 patients were 60% and 41%, respectively. At univariate analysis, chronic graft versus host disease (cGvHd) (p = 0.0005), age (p = 0.01), and state of disease (p = 0.03) were factors affecting LFS whereas chronic GvHd (p = 0.0005), acute GvHd (p = 0.03), age (p = 0.0001), and GvHd prophylaxis (p = 0.01) were factors affecting overall survival. The occurrence of chronic GvHd was correlated with actually delivered TBI dose (p = 0.04). Combined stratification of prognostic factors showed that patients who received the planned total dose of TBI (12 Gy) and were affected by chronic GvHd had higher probabilities of LFS (p = 0.01) and OS (p = n.s.) than patients receiving less than 12 Gy and/or without occurrence of chronic GvHd. Moreover, TBI dose had a significant impact on LFS in patients transplanted in first remission (p = 0.05). At multivariate analysis, TBI dose was an independent factor affecting overall survival (p = 0.05) as well as chronic GvHd (p = 0.001) and age (p = 0.04).

CONCLUSIONS

This retrospective analysis showed that different variables involved in TBI delivery may influence the occurrence of cGvHd and affect prognosis of patients with ALL receiving allogeneic BMT. The total dose of 12 Gy, administered in six fractions over 3 days, appears to be an effective and low toxic regimen for ALL patients transplanted in first remission.

Allogeneic marrow transplantation following cyclophosphamide and escalating doses of hyperfractionated total body irradiation in patients with advanced lymphoid malignancies: a Phase I/II trial

PURPOSE

To define the maximum tolerated dose (MTD) of unshielded total body irradiation (TBI) delivered from dual 60C sources at an exposure rate of 0.08 Gy/min and given in thrice daily fractions of 1.2 Gy in patients with advanced lymphoid malignancies.

METHODS AND MATERIALS

Forty-four patients with a median age of 28 (range 6-48) years were entered into a Phase I/II study. All patients received cyclophosphamide (CY), 120 mg/kg administered over 2 days before TBI. Marrow from human leukocyte antigen (HLA) identical siblings was infused following the last dose of TBI. An escalation-deescalation schema designed to not exceed an incidence of 25% of Grade 3-4 regimen-related toxicities (RRTs) was used. The first dose level tested was 13.2 Gy followed by 14.4 Gy.

RESULTS

None of the four patients at the dose level of 13.2 Gy developed Grade 3-4 RRT. Two of the first eight patients receiving 14.4 Gy developed Grade 3-4 RRT, establishing this as the MTD. An additional 32 patients were evaluated at the 14.4 Gy level to confirm these initial observations. Of 40 patients receiving 14.4 Gy, 13 (32.5%) developed Grade 3-4 RRTs; 46% in adults and 12% in children. The primary dose limiting toxicity was Grade 3-4 hepatic toxicity, which occurred in 12.5% of patients. Noninfectious Grade 3-4 interstitial pneumonia syndrome occurred in 5% of patients. The actuarial probabilities of event-free survival, relapse, and nonrelapse mortality at 2 years were 0.10, 0.81, and 0.47, respectively, for patients who received 14.4 Gy of TBI.

CONCLUSIONS

The outcome for patients receiving 14.4 Gy of TBI was not different from previous studies of other CY and TBI regimens in patients with advanced lymphoid malignancies. These data showed that the incidence of Grade 3-4 RRTs in adults was greater than the 25% maximum set as the goal of this study, suggesting that 13.2 Gy is a more appropriate dose of TBI for adults, while 14.4 Gy is an appropriate dose for children.

Total-body irradiation before bone marrow transplantation. Results of two randomized instantaneous dose rates in 157 patients

One hundred fifty-seven patients referred to the Department of Radiation Oncology of the Hôpital Tenon, Paris, France, between December 10, 1986 and December 31, 1989 for total-body irradiation (TBI) were treated according to the following two techniques: (1) either in one fraction (1000 cGy administered to the midplane at L4 and 800 cGy to the lungs) or (2) in six fractions (1200 cGy on 3 consecutive days to the midplane at L4 and 900 cGy to the lungs). The patients were randomized according to two instantaneous dose rates, called LOW and HIGH, in single-dose (6 versus 15 cGy/min) and hexafractionated (3 versus 6 cGy/min) TBI groups. There were 77 patients in the LOW group and 80 in the HIGH group, with 57 patients receiving single-dose TBI (28 LOW and 29 HIGH) and 100 patients receiving fractionated-dose TBI (49 LOW and 51 HIGH). In March 1991, the 4-year relapse-free and overall survival rates were 58.4% and 52.1%, respectively. The 4-year relapse-free survival and survival rates were 54.9% and 50.7% in the LOW group; 61.9% and 53.5% in the HIGH group (P = 0.69 and 0.82, respectively); 60.3% and 50.4% in the single-dose group; and 57.9% and 53.3% in the fractionated group (P = 0.65 and 0.78, respectively). There was no difference in the incidence of graft versus host disease, interstitial pneumonitis, or venoocclusive disease either between the LOW and the HIGH groups or between the single-dose and fractionated-dose TBI groups. The 4-year estimated cataract incidence was significantly higher in the single-dose HIGH instantaneous dose rate group than in the LOW instantaneous dose rate TBI group (P = 0.049). Multivariate analyses showed that instantaneous dose rate and fractionation do not influence the relapse-free and overall survival rates or the incidence of interstitial pneumonitis.

Marrow transplantation following escalating doses of fractionated total body irradiation and cyclophosphamide--a phase I trial

Thirty-six patients with advanced hematologic malignancy were entered into a Phase I study designed to define the maximum tolerated dose of unshielded total body irradiation delivered from dual 60 Cobalt sources at an exposure rate of 8 cGy/min and given in fractions twice daily for total doses ranging from 12 Gy to 17 Gy. All patients received cyclophosphamide, 120 mg/kg administered over 2 days before total body irradiation. Allogeneic marrow was infused from HLA-identical siblings (n = 29) or one locus HLA incompatible family members (n = 3); three patients received cryopreserved autologous marrow and one patient received syngeneic marrow. The maximum tolerated dose of total body irradiation given as 2 Gy fractions twice a day was 16 Gy. One of eight patients receiving 12 Gy, none of four receiving 14 Gy, three of 20 receiving 16 Gy, and two of four receiving 17 Gy developed severe (Grade 3-4) regimen-related toxicity. The primary dose limiting toxicity was pneumonitis, followed by veno-occlusive disease of the liver, renal impairment, and mucositis. Five patients (14%) are alive, four disease-free 798-1522 days posttransplant. Twenty (56%) relapsed posttransplant. Further investigation of regimens containing 16 Gy of hyperfractionated total body irradiation is warranted to assess anti-tumor efficacy.

The effects of infection prevention regimens on early infectious complications in marrow transplant patients: a four arm randomized study

Three hundred and forty-two patients with hematological malignancies underwent allogeneic marrow transplantation from family donors and were allocated to receive 1) no specific infection prophylaxis in a conventional hospital room (control, 100 patients), 2) prophylactic systemic antibiotics (PSA) in a conventional hospital room (PSA group, 101 patients), 3) decontamination and isolation in a laminar air flow (LAF) room (LAF group, 65 patients) and 4) PSA in an LAF room (LAF+PSA group, 76 patients). Patients were studied for bacterial and fungal complications from the day of admission and until engraftment. LAF isolation was discontinued before engraftment in 27% (LAF+PSA group) to 32% (LAF group) of isolated in 26% (LAF+PSA group) to 27% (PSA group) of patients on prophylactic antibiotics. Septicemia occurred in 41%, 22%, 25% and 10% of patients in the control, PSA, LAF and LAF+PSA group, respectively. The incidence of septicemia was significantly less in the LAF+PSA group than in the control and LAF group with the incidence of septicemia significantly higher in the control group than in any of the other three groups. No other risk factors analyzed in proportional hazards regression tests were associated with septicemia acquisition. It is concluded that effective infection prevention modalities significantly reduce infection morbidity in transplant patients. Since most granulocytopenic transplant patients not receiving PSA will receive empiric or therapeutic broad spectrum antibiotics. The use of PSA in or out of LAF isolation is recommended as an effective modality to reduce septicemia acquisition.

The transfer of antigen-specific humoral immunity from marrow donors to marrow recipients

This study shows that specific humoral immunity could be transferred from marrow donors to marrow recipients. Peripheral blood lymphocytes from long-term human marrow recipients produced IgG anti-tetanus toxoid antibody after in vitro tetanus toxoid stimulation. Antitetanus toxoid antibody biosynthesis was induced using a new tetanus toxoid-specific system employing high lymphocyte numbers, many replicate microcultures, and antigen washout. Anti-tetanus toxoid antibody in 12-day culture supernatants was detected using an enzyme-linked immunosorbent assay. Of 14 marrow recipients, 6 (5 with and 1 without chronic graft-vs-host disease) had lymphocytes that produced anti-tetanus toxoid antibody. Culturing additional numbers of marrow recipient lymphocytes increased in vitro biosynthesis of anti-tetanus toxoid antibody. The presence of circulating serum antibodies to tetanus toxoid and the production of specific anti-tetanus toxoid antibody by peripheral blood lymphocytes from marrow recipients show that engrafted donor lymphocytes can produce in vitro specific antibodies to recall antigens without postgrafting reimmunization.

IgG anti-tetanus toxoid antibody production induced by Epstein-Barr virus from B cells of human marrow transplant recipients

This investigation shows that Epstein-Barr virus (EBV)-activated human B cells from marrow transplant recipients can produce in vitro IgG anti-tetanus toxoid antibody (anti-TT) without booster immunizations with tetanus toxoid (TT). Purified B cells (E-rosette negative) from 8 normal subjects, 6 healthy long-term marrow graft recipients, and 15 long-term marrow graft recipients with chronic graft-vs-host disease (GVHD), were stimulated for 12 days with EBV to induce anti-TT production in culture supernatants. The amount of anti-TT in culture supernatants was quantitated using a enzyme-linked immunosorbent assay. B cells from all 8 normal controls produced in vitro IgG anti-TT after EBV stimulation. Five of 6 healthy recipients had B cells that produced anti-TT after EBV stimulation. Four of 15 recipients with chronic GVHD had B cells capable of producing anti-TT after EBV stimulation. The number of cultures making anti-TT responses was less in those with chronic GVHD than in those without chronic GVHD or normal individuals (P less than 0.001). B cells from patients with chronic GVHD had fewer responses exceeding the overall median of 0.7 ng/ml when compared with the other two groups (P less than 0.03). These data show that B cells of donor origin can produce in vitro IgG anti-TT antibody to tetanus toxoid antigen in a T-independent fashion.

[Bone marrow transplantation in acute leukemia, chronic myeloid leukemia, severe aplastic anemia and stage IV neuroblastoma. Effect of antiviral prevention with anti-CMV-hyperimmunoglobulin and acyclovir]

Bone marrow transplantation was performed between IV/82 and X/85 in 64 patients with acute leukemia (n = 36), chronic myelogenous leukemia (CML; n = 13), severe aplastic anemia (n = 12), and neuroblastoma stage IV (n = 3). Of these patients 57 received allogeneic marrow from HLA-ABCDR identical, MLC-negative sibling donors. Six transplants were performed with syngenic marrow and one with autologous marrow. Of the 64 patients 48 survived 40-1,250 days after transplantation, resulting in a survival rate (SR) of 75% and a survival probability (SP) of 71%. Of the 36 patients suffering from acute leukemia (SR = 64%, SP = 51%), patients with acute myelogenous leukemia (AML) in first complete remission (n = 11; SR = 81%, SP = 76%), as well as patients with acute lymphatic leukemia (ALL) in 1st to 4th complete remission at the time of transplantation (n = 14; SR = 81%, SP = 76%) show a favorable prognosis. A poor survival rate was seen for patients with AML when transplanted in second or partial remission (1/5; SR = 20%), as well as for patients suffering from ALL and transplanted during relapse or partial remission (1/6; SR = 16%). Of 13 patients suffering from CML 12 survived the transplantation free of relapse (SR = 93%, SP = 92%), and one patient died from varicella zoster pneumonia. Of the transplanted patients with severe aplastic anemia, 12 of 13 are surviving with complete hematologic reconstitution; one patient, however, died on day 10 from a sepsis. In our patient group, the SR as well as the SP has been improved through changes in the irradiation protocol concomitant with prophylactic application of anti-CMV hypergammaglobulin, as well as through additional oral medication of Azyklovir. The 41 patients (BMT No. 7-47) with total body irradiation at one time show an SR of 44% and an SP of 41%. The following 46 patients (BMT No. 48-93) have reached an SR of 83% and an SP of 74% under the regimen of fractionated total body irradiation, plus prophylaxis with anti-CMV hypergammaglobulin and Azyklovir. Within this group, no fatal CMV pneumonia was encountered as opposed to six patients lost from CMV pneumonia in the first group.

Methotrexate and cyclosporine compared with cyclosporine alone for prophylaxis of acute graft versus host disease after marrow transplantation for leukemia

We treated 93 patients who had acute nonlymphoblastic leukemia in the first remission or chronic myelocytic leukemia in the chronic phase (median age, 30 years) with high-dose cyclophosphamide and fractionated total-body irradiation, followed by infusion of marrow from an HLA-identical sibling. To evaluate postgrafting prophylaxis for graft versus host disease, we studied these patients in a sequential, prospective, randomized trial that compared the effect of a combination of methotrexate and cyclosporine (n = 43) with that of cyclosporine alone (n = 50). All patients had evidence of sustained engraftment. A significant reduction in the cumulative incidence of grades II to IV acute graft versus host disease was observed in the patients who received both methotrexate and cyclosporine (33 percent), as compared with those who were given cyclosporine alone (54 percent) (P = 0.014). Seven patients who received cyclosporine alone acquired grade IV acute graft versus host disease, as compared with none who received both methotrexate and cyclosporine. Thirty-five of the 43 patients given both methotrexate and cyclosporine and 31 of the 50 patients given cyclosporine are alive as of this writing, at 4 months to 2 years (median, 15 months); the actuarial survival rates in the two groups at 1.5 years were 80 percent and 55 percent, respectively (P = 0.042). We conclude that the combination of methotrexate and cyclosporine is superior to cyclosporine alone in the prevention of acute graft versus host disease after marrow transplantation for leukemia, and that this therapy may have a beneficial effect on long-term survival.

Bone marrow transplantation in the management of childhood cancer

Bone marrow transplantation has become a curative therapy for selected children with leukemia and offers promise as a treatment for certain childhood solid tumors. Complications such as graft-versus-host disease, interstitial pneumonia, and recurrent malignancy continue to affect many patients. As these are overcome, and as methods for T-cell depletion and marrow purging are developed that extend the scope of bone marrow transplantation, it will become an even more significant therapy for childhood malignancy.

Bone marrow transplantation

Bone marrow transplantation is increasingly used to treat a broad spectrum of human diseases including aplastic anemia, leukemia, solid tumors, immune and genetic disorders. In certain circumstances the role of transplantation is reasonably well established, such as aplastic anemia and resistant leukemia. In other circumstances there is controversey as to the role of transplantation such as leukemia in remission. An increasing number of genetic disorders including severe combined immunodeficiency, Wiskott-Aldrich syndrome, osteopetrosis, and Thalassemia have been cured by transplantation. Despite substantial progress, with transplantation that remain to be solved including graft-vs.-host disease, interstitial pneumonia, immune deficiency, and the lack of suitable donors for most potential recipients. These problems and potential approaches are discussed in detail Future direction of research include the application of transplantation to other diseases as well as the use of this approach either as a prelude to solid-organ grafts or as a vehicle for the introduction of new genetic information.

Marrow transplantation for leukemia following fractionated total body irradiation. A comparative trial of methotrexate and cyclosporine

Fifty-six patients, 30-47 yr of age, with leukemia in relapse received allogeneic marrow transplants from HLA-identical siblings. All patients were treated with cyclophosphamide (120 mg/kg) and 7 daily fractions of 2.25 Gy of total body irradiation (TBI) for seven consecutive days. Nine patients (16%) are currently alive and free of disease 324-845 days from transplantation. The actuarial relapse and survival rates at 2 yr were 56% and 9.5% respectively. These data were not remarkably different from those in previous studies using 10 Gy of TBI administered as a single dose. Thirty patients were randomized to receive methotrexate (MTX) and 26 to receive cyclosporine (CSP) as postgrafting prophylaxis for acute graft-versus-host disease (GVHD). The probability of developing significant acute GVHD by day 100 post-transplant was 71% for patients in the MTX group and 45% for patients in the CSP group (p less than 0.05). The probability of relapse was 37% for patients in the MTX group and 70% for patients in the CSP group (p less than 0.05). Transplant-related deaths were more frequent in the MTX group and leukemic deaths were more frequent in the CSP group although this may have been related to an uneven distribution of high-risk patients. Long-term disease-free survival was comparable. Patients in the MTX group had more severe mucositis, more alveolar pneumonias and possibly more deaths due to complications of acute and chronic GVHD. Patients in the CSP group had a higher incidence of hypertension, neurological complications and renal dysfunction.

Cataracts after total body irradiation and marrow transplantation: a sparing effect of dose fractionation

We examined 277 patients, who have been followed for 1 to 12 years after marrow transplantation, for cataract development. In preparation for transplantation, 96 patients with aplastic anemia were conditioned with chemotherapy only, usually cyclophosphamide 50 mg/kg X 4 intravenously, while 181 patients (two with aplastic anemia and 179 with a hematologic malignancy) were conditioned with a regimen of total body irradiation (TBI) and chemotherapy. TBI was delivered from two opposing 60Co sources at an exposure rate of 4 to 8 cGy/min, either as a single dose of 10 Gy (105 patients) or in fractions (76 patients), usually at increments of 2 to 2.25 Gy/day for 6 to 7 days for cumulative doses of 12 to 15.75 Gy. To date, 86 patients have developed cataracts. Kaplan-Meier product limit estimates of the incidence of cataracts for patients given chemotherapy only and no TBI, single-dose TBI, and fractionated TBI are 19, 80, and 18%, respectively. On the basis of proportional hazards regression analyses, patients given single-dose TBI had a relative risk of developing cataracts that was 4.7-fold higher than in patients given fractionated TBI or chemotherapy only (p less than 0.00005), suggesting a significant sparing effect with use of TBI dose fractionation. Addition significant risk factors included the chronic use of steroids posttransplant (highly associated with the presence of chronic graft-versus-host disease), and the diagnoses of acute lymphoblastic or chronic myelogenous leukemia.

Bone marrow transplantation for diseases of childhood

Bone marrow transplantation in childhood is an established treatment modality for aplastic anemia, the acute and chronic leukemias, and severe combined immune deficiency. Recently, experience with this treatment has also been favorable with small numbers of children who have Wiskott-Aldrich syndrome, several types of inherited storage diseases, Fanconi's anemia, thalassemia, infantile malignant osteopetrosis, and selected cases of lymphoma and other solid tumors. The psychosocial impact and financial costs of bone marrow transplantation can be substantial. Multi-institutional, prospective, randomized trials that would compare transplantation and conventional therapy are necessary to establish the indications and precise timing for this procedure. Further development of monoclonal antibodies, a better understanding of the histocompatibility antigen systems, and improvement in pretransplantation conditioning regimens should increase the spectrum of effectiveness for bone marrow transplantation in the coming years.

Allogeneic marrow transplantation

After 15 years of clinical investigation, allogeneic marrow transplantation can be considered the treatment of choice for a variety of hematologic and immunologic diseases. This review has focused upon some of the principles, current results, problems, and future directions in allogeneic marrow grafting.

Total body irradiation as preparation for bone marrow transplantation in treatment of acute leukemia and aplastic anemia

In an attempt to improve survival while minimizing toxicity, many bone marrow transplant centers are now studying the use of cytoreduction regimens with an increased amount of radiation in single-dose or fractionated-exposure schedules for patients with leukemia and aplastic anemia. In order to review the current results, the literature prior to September, 1982 was surveyed and data were tabulated for each transplant center regarding the number of patients receiving transplants, diagnoses, cytoreducation regimen, clinical status, revission duration, relapse rate, causes of death and incidence of interstitial pneumonia. The incidence and severity of cataracts, growth failure, hypothyroidism and second malignant neoplasms were noted, and the data obtained from the literature search were updated and expanded by telephone questionnaire when possible. Marked variation in the technique of transplantation was found among the participating institutions, making it difficult to determine the contribution of the various TBI doses, dose rates and fractionation schedules to the efficacy and toxicity of the combined regimen. In order to define the risk-benefit ratio of the various TBI regimens more clearly, prospective controlled, randomized studies will be required.

A review of the current status and techniques of allogeneic bone marrow transplantation for treatment of leukaemia

Bone marrow transplantation is now an accepted component in the overall therapy of acute and chronic (myeloid) leukaemia for some selected patients. Some of the obstacles to success have been partially overcome. Many advances in supportive care have been made. Pneumocystis carinii and herpes simplex infections are preventable. Effective decontamination of the gastrointestinal tract for bacteria and fungi is now readily achievable and may have reduced the risk of serious systemic infections. New antibiotics which, in combination, are effective in life-threatening infections are under study. Recent developments in the prevention or amelioration of graft versus host disease (GvHD) have included T lymphocyte depletion in the donor marrow and the use of the fungal polypeptide cyclosporin A. Less than 10% of patients would now be expected to succumb to this complication. Outstanding problems remaining to be resolved are the improvement in the antileukaemic conditioning prior to transplantation and the prevention or treatment of cytomegalovirus infection in the seropositive recipient. This infection can cause pneumonitis and is currently the single most frequent transplant related cause of mortality.

Application of bone marrow transplantation in leukaemia and aplastic anaemia

Marrow transplantation is effective treatment for a number of haematological diseases in patients under the age of 50 who have an HLA-identical sibling donor. It is generally successful when used early in the treatment of aplastic anaemia. It is the only treatment that offers long-term disease-free survival for patients with acute leukaemia who have relapsed at least once, with 10-30 per cent apparent cures. Although still somewhat controversial, it appears also to be the treatment of choice for patients with acute non-lymphoblastic leukaemia in first chemotherapy induced remission and for those with chronic myelogenous leukaemia in the chronic phase since approximately 50-60 per cent of these patients are surviving after marrow transplantation in complete remission, apparently cured. Marrow grafting is the only effective treatment for many patients with inherited immunological-deficiency diseases and certain genetic storage diseases. It is being explored for the therapy of patients with lymphoma, Hodgkin's disease, multiple myeloma, small-cell lung cancer, testicular cancer, ovarian cancer and genetic disorders of haematopoiesis. Cures of congenital Fanconi anaemia, Blackfan-Diamond anaemia, osteopetrosis, and paroxysmal nocturnal haemoglobinuria have been achieved by marrow grafting. Genetic disorders associated with haemolytic anaemia and cyclic neutropenia have been cured by marrow grafting in animals. Target disorders for marrow transplantation in humans are thalassaemia major and sickle cell disease, and, indeed, a first successful transplant for treatment of thalassaemia major has recently been described (Thomas et al, 1982). Marrow transplantation has been limited by the fact that many patients do not have HLA-identical siblings and very few have monozygotic twins. The Seattle team has now explored the use of less well-matched family member donors in more than 80 patients with leukaemia. These donors share one HLA haplotype genetically with the patient and are phenotypically identical at two of the three major HLA loci on the other HLA haplotype (Clift et al, 1979). Overall, the post-transplant survival appears more a reflection of the type and stage of the leukaemia than of the marrow donor. Patients with leukaemia grafted in relapse have a projected survival of 20-30 per cent and those transplanted in remission of 50 per cent. The incidence and severity of GVHD may not be significantly different from that of patients given HLA-identical sibling marrow grafts.(ABSTRACT TRUNCATED AT 400 WORDS)

Early infectious complications in allogeneic marrow transplant recipients with acute leukemia: effects of prophylactic measures

One hundred eighty-two patients with acute leukemia underwent allogeneic marrow transplantation and received one of two forms of infection prophylaxis: isolation and decontamination procedures in laminar air flow rooms (90 patients) or prophylactic granulocyte transfusion from a single family member (92 patients). Infection acquisition and survival were analyzed from the time of admission to 100 days posttransplant. There were 20 major local infections in the laminar air flow group and 16 in the prophylactic granulocyte group. Of the patients in the laminar air flow group, 24 (27%) had 27 episodes of bacteremia, while 23 (25%) of the prophylactic granulocyte group had 25 episodes of bacteremia. There were no significant differences in infection acquisition between the two groups during the period of granulocytopenia or after engraftment. The mortality during the first 100 days was 28% for the laminar air flow group and 35% for the prophylactic granulocyte group. Thirteen patients (14%) in the laminar air flow group and five (5%) in the prophylactic granulocyte group died with bacterial or fungal infections. There were no statistically significant differences between the two groups in overall incidence of or mortality from interstitial pneumonitis which was the predominant cause of death. However, the subset of patients who were seronegative for cytomegalovirus antibody at the time of transplant and received granulocytes from seropositive donors had a significantly higher incidence of and mortality from cytomegalovirus interstitial pneumonitis.

Allogeneic marrow transplantation for acute lymphoblastic leukemia in remission using fractionated total body irradiation

Twelve patients with acute lymphoblastic leukemia in second to fourth remission received allogeneic marrow transplants following preparation with cyclophosphamide, 120 mg/kg and 1400 rad of fractionated total body irradiation. Two patients died of interstitial pneumonitis 32 and 62 days post-transplantation. Six patients relapsed between days 59 and 659 and four died of leukemia-related problems. Two patients who relapsed are currently alive, one in remission and one in relapse. Four patients are alive and free of disease 657 to 991 days following transplantation. This disease-free survival was not significantly better than the six of 22 disease-free survivors previously observed following cyclophosphamide and 1000 rad of total body irradiation given in a single exposure.