To Total Body Irradiation Research Articles

Pregnancy Outcomes after Hematopoietic Cell Transplantation (HCT): A Report from the BMT Survivor Study.

Infertility after HCT is a common complication. However, there are some reports indicating that a few patients may retain or recover fertility after HCT. This study was undertaken to determine the prevalence of conception, and outcome of pregnancy in 581 adult women and female partners of men previously treated by autologous (n=234) or allogeneic (n= 347) HCT. Eligible subjects were individuals who had undergone HCT between 1974 and 1998, were transplanted between the ages of 21 and 45, and had survived two or more years after HCT. Median age at HCT was 33.3 years (range, 21.0–44.9), median time since HCT: 7.5 (2.0–24.4). Methodology involved completion of a mailed questionnaire that included items regarding attempts to become pregnant, the occurrence of pregnancy, and the outcome of pregnancy (i.e., live birth, stillbirth, miscarriage, abortion). We abstracted details about the original diagnosis, type of HCT, myeloablative conditioning, and development of chronic graft vs. host disease (cGVHD) from medical records. Twenty-eight patients (4.8%) reported 47 pregnancies after HCT (17 allogeneic and 11 autologous HCT recipients). Of these, 21 males reported 34 pregnancies, while 7 females reported 13 pregnancies. Most pregnancies were uncomplicated and resulted in 40 live births. Risk factors associated with not reporting a conception after HCT included age 30 years or older at time of transplant (odds ratio [OR] = 3.26, 95% confidence interval [CI], 1.20–8.85) and exposure to total body irradiation (TBI) as part of HCT conditioning regimen (OR = 3.84; 95% CI, 1.42–10.34). Risk did not vary significantly by gender, ethnicity, type of transplant, cGVHD status, report of pre-HCT live birth(s), exposure to immunosuppressive agents for GVH prophylaxis or high-dose chemotherapy as conditioning agents. Pregnancy outcomes among the survivors were compared to those of 309 nearest-age siblings who were between the ages of 21 and 45 years at the time of their reported pregnancies. This comparison revealed that the risk for not reporting a conception was significantly increased among HCT recipients (OR = 41.25, 95% CI, 25.83–65.88) and among those with low annual household income (<$20,000: OR=4.45, 95% CI, 1,52–12.99). The outcomes of the 47 pregnancies reported by 28 survivors and those of the 556 pregnancies reported by 215 siblings are shown in the table. Analyses of pregnancy outcomes in this cohort indicated that HCT survivors were more likely than siblings to have a live birth (OR=2.72, 95% CI, 1.05–7.02), and that survivors were not significantly more likely than siblings to have a miscarriage or stillbirth outcome (RR=0.55, 95% CI, 0.21–1.42). This study indicates that conception after HCT is likely to have a successful outcome, although the prevalence of pregnancy after HCT is significantly diminished, especially among patients undergoing HCT at an older age, among those exposed to TBI, and among those with a low household income. These findings should help counsel the patients undergoing HCT.Pregnancy OutcomesNumber of ConceptionsLive BirthStillbirthMiscarriageAbortionIn gestationSurvivors (n=47)40 (85%)1 (2%)4 (9%)02 (4%)Siblings (n=556)413 (74%)6 (1%)94 (17%)37 (7%)6 (1%)

Incidence of Extramedullary Relapse of Acute Myeloid Leukemia Following Transplantation with Busulfan-Based Conditioning Regimens.

Rates of extramedullary relapse are reported to be more than twice as high following transplantation with busulfan-based conditioning regimens (Simpson et al, Bone Marrow Transplantation 1998, Lee et al, Bone Marrow Transplantation 2000) compared to total body irradiation (TBI)-based regimens (Mortimer et al, J. Clin Oncol 1989) in acute myeloid leukemia (AML). Up to 50% of relapses following transplantation with busulfan-based therapies are reported to be extramedullary, with more than 25% as isolated extramedullary relapses. We analyzed 228 consecutive AML patients who underwent allogeneic (n=192) or autologous (n=36) transplantation following busulfan-based conditioning regimens between 2/84 and 12/03. One hundred twenty-three patients were in remission at the time of transplantation, 67 had relapsed disease, and 38 had never achieved remission. One hundred twenty-seven patients received BuCy, 77 received BuCyVP16, and 24 (all autologous) received BuVP16. All patients had a lumbar puncture demonstrating no evidence of leukemia, and all received intrathecal methotrexate prophylaxis prior to receiving busulfan. Seventy-nine patients (35%) relapsed (any site) at a median of 6 months (range, 1 to 44 months) after transplantation. Fifteen patients (7%) relapsed at extramedullary sites, including 7 in the CNS. Ten patients (4%) had isolated extramedullary relapses at a median of 13 months (range, 1 to 44 months) after transplantation. Four had isolated CNS relapses, and 4 had isolated cutaneous relapses. Of patients transplanted in remission, only 2 relapsed at extramedullary sites, including one patient with an isolated CNS relapse.This retrospective study includes a substantially larger cohort of patients with longer follow-up than prior studies examining extramedullary relapse in patients with AML following transplantation with busulfan-based conditioning. In contrast to other reports, these results demonstrate that the incidence of extramedullary relapse is comparable to that reported with TBI-based conditioning regimens for patients with AML.

Effect of whole body hyperthermia (39°C, 1 h) on radiation-induced apoptosis in Swiss mice

Mild whole body hyperthermia (WBH) treatment when given prior to radiation exposure is known to protect mice against radiation-induced hemopoietic death. This radioprotective effect seems to be mediated through WBH-induced cytokines and growth factors. Exposure to total body irradiation (TBI) also induces cell death by apoptosis in animal cells. The present studies were therefore carried out to investigate whether WBH pretreatment could protect mice against radiation-induced apoptotic death. The extent of apoptosis in bone marrow cells derived from mice at different time intervals after WBH, TBI and whole body hyperthermia treatment given 20 h prior to total body irradiation (WBH+TBI) treatments was studied by three independent methods namely DNA ladder assay, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling assay and caspase-3 assay. The studies have revealed that the mild WBH treatment (39°C, 1 h) when given 20 h prior to TBI (8 Gy) results in reduction in TBI-induced apoptosis. The results imply that WBH-induced impairment of apoptosis may have some role in WBH-induced radioprotection in Swiss mice.

Severe DNA damage in K-ras gene patterns of PCR products in mice fed a 1% protein diet and exposed to a high dose of radiation.

K-ras gene patterns of PCR products in response to total body irradiation (TBI) in mice fed four kinds of diets were assessed. Male mice were fed a 1% protein diet, 7% protein diet, 20% protein diet, or a 60% protein diet for 4 weeks, received TBI at a dose of 0, 2, or 6 Gy, and were sacrificed 4 weeks post-TBI. Severe DNA damage in mice fed a 1% protein diet with a high dose of radiation exposure (TBI at 6 Gy) was observed.

High levels of apoptosis induced by total body irradiation in mice fed a low protein–low vitamin E diet

Apoptosis in response to total body irradiation (TBI) in mice fed four kinds of diets was assessed. Male mice were fed a low protein–low vitamin E diet, a low protein–basal vitamin E diet, a basal protein–low vitamin E diet or a basal protein–basal vitamin E diet for 2 weeks, then received TBI at a dose of 0, 1 or 4 Gy, and were sacrificed 4 h after TBI. Apoptosis was assessed according to the appearance of DNA fragmentation patterns [DNA laddering and positive in situ end-labeling by terminal transferase ( TUNEL) assay] and apoptotic index (AI). Electrophoresis of DNA from the spleen in the groups that did not receive TBI showed no cleavage, whereas that of DNA in the groups with 4 Gy of TBI displayed a ladder pattern, indicative of internucleosomal cleavage characteristic of apoptosis. In the groups with 4 Gy of TBI, apoptosis was enhanced in the low protein–low vitamin E group.

Chronic graft-versus-host disease and late effects after hematopoietic stem cell transplantation.

Late effects following HSCT are related to either the transplant process or to the transplant preparative regimen. Problems related to the transplant process include delayed recovery of the immune system and chronic GVHD. Chronic GVHD presents between 3-14 months post-HSCT in approximately 20% of matched sibling transplants and 40% of matched unrelated donor recipients. Most commonly involved sites are skin, mouth, liver, gastrointestinal tract, and eye. Patients with platelet count < 100,000/ml and receiving cortocosteroid therapy at day 80 with any clinical manifestations of chronic GVHD require prolonged immune suppressive therapy with prednisone, cyclosporine +/- other agents. Treatment should be administered until all clinical and pathological signs and symptoms of chronic GVHD have resolved which may take one to several years. Problems related to the transplant preparative regimen include those involving the endocrine system, eyes, lungs, bone, and development of secondary malignancies. Endocrine deficiencies include growth failure with growth hormone (GH) deficiency, overt hypothyroidism, primary gonadal failure, Type 1 or Type 2 diabetes, and exocrine pancreatic insufficiency. These problems develop at any time post-HSCT, but usually occur within the first few years and should be treated with appropriate hormone supplementation. Eye problems are primarily related to development of cateracts secondary to total body irradiation (TBI) or prolonged corticosteroid use. Cateracts developing after fractionated frequently do not require removal. Pulmonary problems may be due to bronchiolitis obliterans (BO) or to restrictive lung disease. BO may be associated with chronic GVHD and may respond to chronic GVHD therapy. Restrictive lung disease does not occur for many years after HSCT. There is not therapy for this problem. Development of decreased bone mineral density (BMD) is related to GH deficiency and/or corticosteroid therapy. Treatment includes withdrawal of corticosteroids, administration of GH and calcium, Vitamin D and antiresorptive agents. All malignant disease survivors are at risk for development of secondary malignancies, including survivors of HSCT. Recipients of TBI are at highest risk as are children. All pediatric and adult survivors of HSCT should be followed for their life-time for development of delayed effects of transplantation.

Effect of whole body hyperthermia on radiation therapy of transplanted fibrosarcoma in Swiss mice

The exposure of normal mice to whole body hyperthermia (1h WBH at 39 or 40°C), 20 or 48h prior to total body irradiation (TBI) with lethal doses of n -rays affords significant protection as assessed by survival. The radioprotective effect of WBH, as observed in normal mice, diminished in tumour bearing mice depending upon the size of tumour. Treatment of tumour bearing mice with mild WBH, 20h prior to local irrradiation (LIR), did not protect the transplanted tumour against radiotherapy with a single dose of 20Gy or fractionated dose (in five fractions) of 7.5Gy on alternate days. In fact, mild WBH treatment enhanced the tumour regression and increased the mean survival time after fractionated dose therapy. However, the prior mild WBH was found to be ineffective in protecting normal tissue, as assessed by skin contraction after local irradiation (50Gy). This indicates that mild WBH treatment given 20 h prior to local radiotherapy enhances fibrosarcoma tumour regression but cannot protect skin (normal tissue) against local irradiation. It appears that radioprotection of animals by WBH may be the consequence of its radioprotective effect on haemopoietic tissues mediated through certain cytokines. Perhaps WBH may not have a radioprotective effect on other tissues, as evident from skin contraction studies.

Increases in 4-hydroxynonenal and hexanal in bone marrow of rats subjected to total body X-ray irradiation: association with antioxidant vitamins.

Radiation-induced lipid peroxidation and its association with antioxidant vitamins in the bone marrow (BM), of rats subjected to total body irradiation (TBI) of X-rays at a dose of 3 Gy was investigated. The concentration of vitamin C in the BM decreased at 4 h, and reached about 2% of the control level at 24 h after irradiation. The concentration of vitamin E in the BM also decreased to 43% at 24 h. Corresponding to the decrease in vitamin E concentration, the concentration of 4-hydroxynonenal (HNE) in the BM increased 2.5-fold at 24 h. Similarly, increases in the concentrations of hexanal and thiobarbituric acid-reactive substances (TBA-RS) were detected in the BM. In the plasma, these parameters of lipid peroxidation were unchanged up to 48 h, but were increased at 96 h after irradiation. Four days of vitamin E administration to rats (p.o. 460 mg/kg body weight) prior to the 3 Gy X-irradiation increased the vitamin E concentration in the BM to 1.3-fold the control level, but did not attenuate the increases in HNE and hexanal in the BM. The slight accumulation of vitamin E in the BM as a result of the vitamin E treatment may be partly related to this lack of vitamin E effect.

Thiotepa improves allogeneic bone marrow engraftment without enhancing stem cell depletion in irradiated mice.

Thiotepa (TT) has long been considered for inclusion in clinical bone marrow transplant (BMT) conditioning regimens in an attempt to prevent allograft rejection and leukemia relapse. These studies have been encouraged by initial murine experiments showing a clear improvement in allogeneic bone marrow engraftment with addition of TT to total body irradiation (TBI) where it was assumed that TT enhances donor-type chimerism via ablation of competing stem cells in the recipient. The aim of the present study was to re-evaluate the hematological toxicity of TT among different stem cell subsets that included primitive cells capable of long-term repopulation and to assess how the combination of TT with TBI influences the development of donor engraftment in both syngeneic (B6-Gpi-1a --> B6-Gpi-1b) and H-2 compatible allogeneic (BALB.B10 --> B6) BMT models. At 24 h after TT (20 mg/kg) the femoral content of different stem cell subsets was determined from the frequency of transient repopulating, and the more primitive cobblestone area-forming, cells (CAFCs) growing in stroma-supported cultures. This assay showed a large TT-induced depletion (2% survival) of early clones developing at day 7 in culture but survival recovered towards normal for later appearing clones developing from more primitive CAFC subsets. The sparing of these primitive stem cells was reflected as undetectable levels of donor marrow repopulation in recipients given TT followed by syngeneic BMT. Addition of TT to TBI did not significantly improve long-term engraftment of syngeneic marrow while this combination had a dramatic effect in allogeneic BMT by preventing allograft rejection. In this respect TT shares similar properties with cyclophosphamide and suggests that the large improvement of allogeneic stem cell engraftment is attributable to the immune suppressive properties of TT rather than to its toxicity against host primitive stem cells.

Stem Cell Factor Enhances the Survival of Murine Intestinal Stem Cells after Photon Irradiation

Recombinant rat stem cell factor (SCF) has been shown to decrease lethality in mice exposed to total-body irradiation (TBI) in the lower range of lethality through radioprotection of hematopoietic stem cells and acceleration of bone marrow repopulation. This study evaluates the effect of SCF on the survival of the intestinal mucosal stem cell after TBI. This non-hematopoietic stem cell is clinically relevant. Gastrointestinal toxicity is common during and after abdominal and pelvic radiation therapy and limits the radiation dose in these regions. As observed with bone marrow, the administration of SCF to mice prior to TBI enhanced the survival of mouse duodenal crypt stem cells. The maximum enhancement of survival was seen when 100 micrograms/kg of SCF was given intraperitoneally 8 h before irradiation. This regimen increased the survival of duodenal crypt stem cells after 12.0 Gy TBI from 22.5 +/- 0.7 per duodenal cross section for controls to 30.0 +/- 1.7 after treatment with SCF (P = 0.03). The TBI dose producing 50% mortality at 6 days (LD50/6) was increased from 14.9 Gy for control mice to 19.0 Gy for mice treated with SCF (dose modification factor = 1.28). These findings demonstrate that SCF has radioprotective effects on a non-hematopoietic stem cell population and suggest that SCF may be of clinical value in preventing radiation injury to the intestine.

Radiation-induced bone abnormalities after bone marrow transplantation for childhood leukemia.

To identify bone abnormalities related to total-body irradiation (TBI) in long-term survivors of bone marrow transplantation (BMT) for childhood leukemia. The authors obtained skeletal surveys of 10 survivors of childhood leukemia, ages 5-27 years, who had undergone BMT 7-9 years previously. Pretransplantation "conditioning" regimens were composed of chemotherapy and TBI in doses of 12 or 14.4 Gy. Of the six survivors who received TBI before age 8 years, five had osteochondromas and three had metaphyseal growth abnormalities. One also had slipped femoral capital epiphysis. Findings in the four remaining patients, who received TBI at ages 12-19 years, were less severe and less clearly related to TBI (mild scoliosis in two cases, avascular necrosis of the femoral condyles in one, and a femoral enchondroma in one). Skeletal abnormalities, previously recognized as sequelae of local external-beam irradiation in children, may occur in long-term survivors of BMT who have received TBI. Younger patients appear to be at the greatest risk.

Potential Use of Interleukin-6 in Bone Marrow Transplantation: Effects of Recombinant Human Interleukin-6 After Syngeneic and Semiallogeneic Bone Marrow Transplantation in Mice

AbstractThe potential of recombinant glycosylated human interleukin-6 (rhlL-6) for enhancing immunohematopoietic reconstitution and survival after syngeneic and semiallogeneic bone marrow transplantation (BMT) in BALB/c mice subjected to total body irradiation (TBI) was investigated. rhlL-6 produced enhanced reconstitution of white blood cells as assessed on days 8 and 14 after syngeneic BMT and of platelets as assessed on day 10. Moreover, rhlL-6 treatment produced significant improvement of survival in lethally irradiated mice receiving either syngeneic or semiallogeneic BMT with limiting number of BM cells. This effect of IL-6 was not seen with large BM cell inocula producing high survival by themselves. rhlL-6 showed no toxic effects and did not affect the survival of mice that were lethally irradiated but not reconstituted by BM cells. However, the sensitivity of mice to sublethal irradiation was increased by rhlL-6 in the absence of BM cell transplantation. In experimental conditions inducing graft-versus-host disease (GVHD), in which lethally irradiated (BALB/c × C57BL/6)F1 mice received mixtures of BM and spleen cells from C57BL/6 donors, rhlL-6 was found to enhance GVHD manifestations. No consistent enhancement of T-cell in vitro proliferative responses to allogeneic spleen cells or T- and B-cell-dependent mitogens were seen in the splen-ocytes obtained from recipients of syngeneic or semiallogeneic BMT. Our data suggest that rhlL-6 may be useful in BMT procedures to enhance thrombopoiesis and hematologic recovery, as well as to increase overall survival rates. In addition, the potentiation of GVHD, which is considered to correlate with graft-versus-leukemia effects, may be of interest in enhancing GVHD-dependent antitumor effects in protocols combining radiochemotherapy with BMT.

Potential use of interleukin-6 in bone marrow transplantation: effects of recombinant human interleukin-6 after syngeneic and semiallogeneic bone marrow transplantation in mice

The potential of recombinant glycosylated human interleukin-6 (rhIL-6) for enhancing immunohematopoietic reconstitution and survival after syngeneic and semiallogeneic bone marrow transplantation (BMT) in BALB/c mice subjected to total body irradiation (TBI) was investigated. rhIL-6 produced enhanced reconstitution of white blood cells as assessed on days 8 and 14 after syngeneic BMT and of platelets as assessed on day 10. Moreover, rhIL-6 treatment produced significant improvement of survival in lethally irradiated mice receiving either syngeneic or semiallogeneic BMT with limiting number of BM cells. This effect of IL-6 was not seen with large BM cell inocula producing high survival by themselves. rhIL-6 showed no toxic effects and did not affect the survival of mice that were lethally irradiated but not reconstituted by BM cells. However, the sensitivity of mice to sublethal irradiation was increased by rhIL-6 in the absence of BM cell transplantation. In experimental conditions inducing graft-versus-host disease (GVHD), in which lethally irradiated (BALB/c x C57BL/6)F1 mice received mixtures of BM and spleen cells from C57BL/6 donors, rhIL-6 was found to enhance GVHD manifestations. No consistent enhancement of T-cell in vitro proliferative responses to allogeneic spleen cells or T- and B-cell-dependent mitogens were seen in the splenocytes obtained from recipients of syngeneic or semiallogeneic BMT. Our data suggest that rhIL-6 may be useful in BMT procedures to enhance thrombopoiesis and hematologic recovery, as well as to increase overall survival rates. In addition, the potentiation of GVHD, which is considered to correlate with graft-versus-leukemia effects, may be of interest in enhancing GVHD-dependent antitumor effects in protocols combining radiochemotherapy with BMT.

Radiation dose as a factor in host preparation for bone marrow transplantation across different genetic barriers.

Engraftment of donor bone marrow in relation to total body irradiation (TBI) dose was studied in syngeneic (B6----B6), MHC-compatible (BALB.B----B6) and MHC-incompatible allogeneic (BALB/c----B6) murine bone marrow transplantation (BMT) models. For each BMT combination radiation dose-response curves were obtained from stable long-term bone-marrow chimerism using Gpi-1 phenotyping and this was compared with the growth of exogenous CFU-S. Syngeneic engraftment required the lowest TBI doses limited to ablation of host haemopoietic stem cells. Resistance against H-2-compatible allogeneic engraftment was evident at low radiation doses (less than 5.5 Gy) but at 6 Gy and above the level of chimerism was comparable to syngeneic transplants, which indicated effective immunosuppression. Higher TBI doses were needed for engraftment as the immunological barrier was increased using fully H-2-incompatible allogeneic transplants. The high TBI dose (9.5 Gy) needed for suppression of spleen endocolonies in the CFU-S assay meant that rejection of exogenous bone marrow was evident only across the larger immunological barriers. When the fully allogeneic combination was reversed (B6----BALB/c) both CFU-S and chimerism data showed less rejection. The steep dose-response relationships show how engraftment is critically dependent on TBI dose, as well as the genetic disparity between donor and host.

Adjunctive therapy (whole body hyperthermia versus lonidamine) to total body irradiation for the treatment of favorable b-cell neoplasms: a report of two pilot clinical trials and laboratory investigations

Based on earlier clinical and preclinical investigations, we designed two different pilot trials for patients with nodular lymphoma or chronic lymphocytic leukemia. These studies evaluated the use of either 41.8C whole body hyperthermia (WBH), or the nonmyelosuppressive chemotherapeutic drug, lonidamine (LON), as an adjunct to total body irradiation (TBI) (12.5 cGy twice a week, every other week for a planned total dose of 150 cGy). Whole body hypertbermia was initiated approximately 10 min after total body irradiation; lonidamine was administered orally (420 mg/m 2) on a daily basis. Although entry to the studies was nonrandomized, the two patient populations were accrued during the same time frame and were comparable in terms of histology, stage of disease, performance status, and prior therapy. Of 8 patients entered on the TBI/WBH study, we observed 3 complete responses (CR), 4 partial responses (PR), and 1 improvement (i.e., a 48% decrease in tumor burden). Of 10 patients entered in the TBI/LON study, there was 1 CR and 4 PR. For the TBI/WBH study, myelosuppression was not treatment limiting; there were no instances of infection or bleeding and platelet support was never required. The median survival time for the TBI/WBH study is 52.5 months based on Kaplan Meir estimates. Two patients remain in a CR. The median time to treatment failure (MTTF) is 9.4 months (90% confidence interval = 7–15.4 months). In the TBI/LON study, 50% of patients receiving TBI required treatment modification due to platelet-count depression during therapy, but there were no instances of infection or bleeding. Frequently observed LON-related toxicities included myalgias, testicular pain, photophobia and ototoxicity. For the TBI/LON study, median survival is 7.6 months; MTTF was 2.4 months. In analyzing the results of these pilot studies, our subjective clinical impressions lead to the hypothesis that WBH protected against TBI-induced thrombocytopenia during therapy, whereas LON had no effect on TBI-induced myelosuppression. This speculation was tested and confirmed in a series of in vitro and in vivo experiments.

Cyclophosphamide treatment expands the circulating hematopoietic stem cell pool in dogs.

Increased numbers of circulating granulocyte-monocyte precursor cells (CFUc) have been observed in the peripheral blood of man after antineoplastic chemotherapy. We have developed a canine model to study the biologic significance of this phenomenon for hematopoietic reconstitution following hematopoietically lethal exposure to total body irradiation (TBI). After cyclophosphamide administration, a 16-fold expansion of circulating CFUc numbers was observed during the period of rapid leukocyte recovery that occurred after the chemotherapy-induced leukocyte nadir. We had previously noted this association between leukocyte recovery and CFUc expansion in our human studies. After 900 rad TBI hematopoietic reconstitution was attempted with autologous, cryopreserved collections of peripheral blood mononuclear cells obtained either at times of post-cyclophosphamide CFUc expansion (group A, 14 dogs) or without CFUc expansion (group B, 12 dogs). Asd compared to group B collections, group A collections contained 11-fold more CFUc and were 12.5-fold more potent in fostering hematopoietic recovery after TBI. These results suggest that the expansion of CFUc numbers we observed was accompanied by a similar expansion of more primitive hematopoietic stem cell numbers. We conclude that chemotherapy-induced expansion of circulating CFUc numbers appears to be of substantial import in effecting hematopoietic reconstitution--an observation that may be of significance for further studies of autologous hematopoietic reconstitution in man.