Liver transplantation followed by allogeneic hematopoietic stem cell transplantation for atypical mevalonic aciduria.

Mevalonic aciduria because of mutations of the gene for mevalonate kinase causes limited synthesis of isoprenoids, the effects of which are widespread. The outcome for affected children is poor. A child with severe multisystem manifestations underwent orthotopic liver transplantation at age 50 months for the indication of end-stage liver disease. This procedure corrected liver function and eliminated portal hypertension, and the patient showed substantial improvement in neurological function. However, autoinflammatory episodes continued unabated until hematopoietic stem cell transplantation was performed at 80 months. Through this complex therapy, the patient now enjoys a high quality of life without significant disability.

Weight loss and reduced body mass index: a critical issue in children with multiorgan chronic graft-versus-host disease.

Weight loss and malnutrition are major problems in patients with chronic graft-versus-host disease (GVHD). In adults, low body mass index (BMI) is a predictor for mortality; however, weight loss and BMI have not been studied in pediatric chronic GVHD. A retrospective study on 18 children with extensive chronic GVHD was completed. Median age at SCT was 12.3 (range 0.6-23) years; age at chronic GVHD diagnosis was 12.5 (1-23) years. Patients with multiorgan involvement had a mean maximal decrease in BMI of 20.9% and most dropped below 10th percentile in expected weight-for-age. This change in BMI not only indicates a significant decrease in weight but often a plateau in stature. In contrast, patients with one organ system involved had a mean maximal decrease in BMI of 5% and did not fall below 10th percentile. All patients with multiorgan involvement required salvage therapy beyond steroids and CSA. Three patients died due to complications of chronic GVHD. Weight loss and malnutrition (as reflected by a decrease in BMI) are clinically significant issues in children with multisystem chronic GVHD. Weight loss is likely another systemic manifestation of the disease and may contribute, along with other factors such as increased immunosuppression and infection, to increased mortality in this group.

Treatment with nephrectomy only for small, stage I/favorable histology Wilms' tumor: a report from the National Wilms' Tumor Study Group.

PURPOSE: Children younger than 24 months with small (< 550 g), favorable histology (FH) Wilms tumors (WTs) were shown in a pilot study to have an excellent prognosis when treated with nephrectomy only. PATIENTS AND METHODS: A study of nephrectomy only for the treatment of selected children with FH WT was undertaken. Stringent stopping rules were designed to insure closure of the study if the true 2-year relapse-free survival rate was 90% or lower. RESULTS: Seventy-five previously untreated children younger than 24 months with stage I/FH WTs for which the surgical specimen weighed less than 550 g were treated with nephrectomy only. Three patients developed metachronous, contralateral WT 1.1, 1.4, and 2.3 years after nephrectomy, and eight patients relapsed 0.3 to 1.05 years after diagnosis (median, 0.4 years; mean, 0.51 years). The sites of relapse were lung (n = 5) and operative bed (n = 3). The 2-year disease-free (relapse and metachronous contralateral WT) survival rate was 86.5%. The 2-year survival rate is 100% with a median follow-up of 2.84 years. The 2-year disease-free survival rate (excluding metachronous contralateral WT) was 89.2%, and the 2-year cumulative risk of metachronous contralateral WT was 3.1%. CONCLUSION: Children younger than 24 months treated with nephrectomy only for a stage I/FH WT that weighed less than 550 g had a risk of relapse, including the development of metachronous contralateral WT, of 13.5% 2 years after diagnosis. All patients who experienced relapse on this trial are alive at this time. This approach will be re-evaluated in a clinical trial using a less conservative stopping rule.

Monosomy 7 associated with pediatric acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS): successful management by allogeneic hematopoietic stem cell transplant (HSCT).

Pediatric acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS) with monosomy 7 is associated with poor disease-free survival when treated by conventional chemotherapy, immunosuppression or supportive measures. Hematopoietic stem cell transplant (HSCT) may improve outcomes; however, data to support this are limited. To better understand the curative potential of HSCT in these patients, all cases of AML and MDS with monosomy 7 treated by two transplant programs (1992 to present) were reviewed. A total of 16 patients were treated, all by allogeneic HSCT. Primary diagnoses were MDS (N = 5), therapy-related MDS (N = 3), AML (N = 5) and therapy-related AML (N = 3). In all, 11 patients (69%) survive event-free at 2 years with median follow-up of 986 days (range 330-2011 days). Toxicity caused deaths of the five nonsurviving patients, four of whom were transplanted with active leukemia. Allogeneic HSCT is effective therapy for childhood AML and MDS associated with monosomy 7, particularly for patients with AML in complete remission and MDS.

Developing a pediatric outpatient transplantation program. The Children's Memorial Hospital experience.

We describe the development of a pediatric outpatient transplant program and our initial experience with autologous and allogeneic transplants performed partially or completely in the outpatient setting. Forty-eight autologous and seven allogeneic transplants have been performed in our institution in the outpatient setting between June 1994 and July 2000. The ablation used for the autologous outpatient transplants was VP-16 1000 mg/m2/ day as a continuous infusion for 2 days and Carboplatinum 667mg/m2/day for 2 days. The autologous inpatient transplants received Thio-tepa 300-mg/ m2per day x 3 days and cyclophosphamide 60 mg/kg/day for 4 days. For those patients who received an immune-ablative allogeneic outpatient transplant, the regimen consisted of Fludarabine 30 mg/m2/day for 6 days, followed by busulfan for children less than five years of age 1 mg/kg/dose x 8 doses and for those five years and older 0.8 mg/kg/dose x 8 doses, followed by ATG 40mg/kg/day x 4 days. Engraftment was complete in all transplants achieving an ANC >500 for the outpatient transplant in 15 days (10-35) vs. the inpatient in 15 days (14-58). This was not statistically significant. They achieved un-sustained platelets >20.0 by day 19 (14-58) for the outpatients and day 32 10-64) for the inpatient. The allogeneic immune ablative transplants were considered engrafted when their VNTRs were greater that 30% which was achieved at a median of 13 days (10-27). The economic data showed a statistically significant decrease in charges and direct costs between the outpatient (median charges $30 775, direct costs $8 389) and the inpatient (median charges $99 838, direct costs $42 757) transplants (p0.001). There was no difference in morbidity and mortality between the two groups but the use of empiric amphotericin B was markedly decreased in the outpatient transplants. In conclusion it is feasible and less costly to perform autologous hematopoietic stem cell transplants in the outpatient setting with no increase in morbidity and mortality. For the allogeneic transplants there is not yet enough data to establish a similar conclusion.

Identification of two pseudogenes with sequence homology to human and gorilla MHC class IA genes: ancestral haplotype in the Filipino population.

While characterizing exons 2 and 3 of the class I human leukocyte antigen (HLA)-A locus in human lymphocytes, two similar but unexpected PCR products were detected in six samples of Filipino ethnicity. A nucleotide sequence analysis of the two amplicons, tentatively named HLA-COQ and HLA-DEL, rendered them as two novel and seemingly related sequences, both with homology to the gorilla and human major histocompatibility complex (MHC) A locus. Exon 2 is similar to the published human pseudogenes HLA-BEL, HLA-Y, and to primate MHC Gogo-A*0501, differing by 2 bp from HLA-BEL, and HLA-Y, and by 4 bp from Gogo-A*0501. Exon 3 is most similar to HLA-A*2902 and A*310102, differing by 7 bp from A*2902, and by 8 bp from A*31012. Genomic sequence comparison of exons 1 to 8 indicates that their closest published match is to the Gogo-A*0501. Complete typing at the HLA-A, -B, -C, DRB1, and DRB5 loci for the six samples yielded the reoccurring types: HLA-A*3401, -B*1521/1525, -Cw*0403, -DRB1*150201, and DRB5*010101. Thus far, HLA-COQ and HLA-DEL have been detected only in Filipino samples containing these HLA types. The HLA-COQ gene is nonfunctional based on a stop codon located in exon 4. HLA-DEL is also a nonfunctional gene because of the dual cytosine insertion in exon 4, with a reading frame shift generating a stop codon downstream. Parsimony analysis of the two pseudogenes with 31 other primate A locus coding regions resulted in a phylogenetic tree that segregated the two pseudogenes with the Gogo-A*0501, suggesting that HLA-COQ, HLA-DEL, and Gogo-A*0501 evolved from a common ancestral allele.

Rapid immune reconstitution following autologous hematopoietic stem cell transplantation in children: a single institution experience.

In this retrospective study, we review the immune reconstitution of children undergoing autologous hematopoietic stem cell transplantation. A total of 125 patients underwent autologous transplantation between 1992 and 2000. The report includes data on 58 patients. Data were not available on the remaining patients who either died before testing or data were not obtained. The parameters evaluated include: (a) immunophenotype by flow cytometry to quantify lymphocyte subpopulations (b) mitogen stimulation assays, and (c) quantitative immunoglobulins. The analysis reveals that CD3+ cells did not reach the normal range during the first year post-transplant. The median percentage of CD4+ cells was below normal up to 6 months post-transplant, while the absolute number remain low throughout the first year. The CD8+ percentage and absolute numbers remain normal at all times post-transplant. The CD19+ cells were also normal post-transplantation. The mitogen lymphocyte stimulation was normal in 27 out of 31 patients tested after 6 months post-transplant. Our analysis of immune reconstitution shows a similar pattern to previous studies with a faster recovery of the CD4/CD8 ratio, especially in those patients who did not receive TBI. In conclusion, the observed deficiencies are transient and have very little clinical significance because, historically, the rate of serious infections is low despite prolonged immune suppression. The recovery post-autologous transplant is fast.

Pharmacokinetics of high dose thiotepa in children undergoing autologous bone marrow transplantation.

Pharmacokinetics of high dose thiotepa was studied in 10 children who received this drug as a 2 h infusion at a dose of 300 mg/m2 daily for 3 days. The thiotepa was quantitated using a modification of a previously published gas chromatographic method. Samples were obtained at predetermined times post infusion. The peak plasma concentrations immediately following the infusion ranged from 5.5 to 25.2 (2.0 +/- 6.6) mg/l and the 8 h post infusion ranged from 0.06 to 0.7 (0.32 +/- 0.21) mg/l. The disposition of thiotepa was best described as a simple one compartment open model. The mean (+/- SEM) values for apparent elimination half-life (t1/2 beta), total plasma clearance (CL) and steady volume of distribution (VDss) were 1.3 x h, 11.25 (1.73) l/h/m2 and 19.38 (2.58) l/m2 respectively. In conclusion the pharmacokinetics of high dose thiotepa in children between 2 and 12 years of age do not appear to vary from those reported in children receiving 75 mg/m2 or adults receiving similar doses.

Platelet chimerism by polymerase chain reaction (PCR) utilizing variable number of tandem repeats (VNTR) in allogeneic stem cell transplant in children: a new novel approach to full chimerism analysis.

Evaluation of chimerism following allogeneic transplantation has been performed traditionally focusing on two cellular compartments, namely lymphoid and myeloid. However, none has been described so far to evaluate platelet chimerism. In order to achieve full chimerism in all three cellular compartments, we prospectively obtained 138 samples of peripheral blood in 55 patients at different post transplant periods following allogeneic hematopoietic transplantation. Evaluation of chimerism was performed utilizing tests of variable number of tandem repeat (VNTR) and sex determination by quantitative polymerase chain reaction (PCR). Tests for platelet chimerism using platelet-rich plasma were simultaneously analyzed with samples for T-cell lymphoid and myeloid compartments. Complete donor chimerism was noted in 49 of 55 patients (89%), while the remaining six have split chimerism ranging from 34 to 98%. There is significant difference (P=0.0004) between the percentages of donor DNA in all three cellular compartments comparing the means+/-s.e.m. (myeloid 95.60+/-0.9, T-cell lymphocytes 87.6+/-1.9, and the platelets 90.8+/-1.5); however, comparison between the medians is not statistically significant. This study represents an additional step towards achieving full chimerism and the observation may help reduce the number of unnecessary platelet transfusions once chimerism is noted in that cellular compartment.

Analysis of parameters affecting engraftment in children undergoing autologous peripheral blood stem cell transplants.

Eighty-three pediatric patients underwent autologous peripheral blood stem cell transplants at a single institution and were included in a study evaluating the correlations between five engraftment parameters and the time to both neutrophil and platelet recovery. The parameters included: the number of nucleated cells per kg (TNC/kg), the absolute CD34+ cell content per kg (CD34+/kg), the number of mononuclear cells per kg (MNC/kg), the number of BFU-E/kg, and the number of CFU-GM/kg. A two-tailed Mann-Whitney test (alpha = 0.05) was used to determine if there were significant differences between patients with neuroblastoma (n = 45) and patients with other diagnoses (n = 38). No statistically significant differences existed between neuroblastoma patients and patients with other diagnoses. Therefore, the two groups of patients were pooled together. Data were analyzed using both a univariate and multivariate correlation method and Student's t-test (alpha = 0.05). Two statistically significant logarithmic relationships were found. The first relationship was between MNC/kg and time to ANC reconstitution (P = 0.05). The second relationship was between CFU-GM/kg and time to platelet recovery (P = 0.01). Based on the statistical data, we conclude that there is no correlation between nucleated cell dose, CD34+ cell dose, and BFU-E content with either neutrophil or platelet recovery. Accordingly, in this study MNC cell dose per kilogram was the most important parameter predicting the length of time between graft infusion and neutrophil recovery while CFU-GM content per kilogram was the most important parameter predicting the length of time until platelet recovery.

Red cell salvage and reinfusion in pediatric bone marrow donors.

We evaluated the use of a semi-automated processing technique to salvage red blood cells from pediatric bone marrow donors to minimize the risk of severe anemia following bone marrow harvest and ABO incompatibility in the recipient. Sixty healthy, HLA-matched, pediatric donors of bone marrow hematopoietic cells with a median age 8.0 years (2-19) were studied. Thirteen of the donor-recipient pairs were ABO incompatible. There were 60 recipients with a median age of 8.6 years (2 months to 20.8 years). Bone marrow was harvested under general anesthesia, filtered in the operating room and then transferred to the stem cell laboratory for processing. Samples were obtained for cell count, CD34+ quantification, colony assay, viability, and bacteriologic cultures before and after processing. The cells were processed in a semi-automated closed system (Stericel, Terumo) by density gradient separation with Ficoll-Hypaque and then washed. Two aliquots were obtained: one containing the mononuclear cell layer to be infused to the recipient and the other the washed red cells to be infused to the donor. The median volume harvested was 608 +/- 40.42 ml (278-1409), while the final volume infused was 174 +/- 10.75 ml (30.2-380) P < 0.0001, representing a decrease of 72% of the volume infused. The nucleated cell count harvested was 1.6 x 10(10) +/- 0.1 (0.56-3.2), while the count infused was 6.9 x 10(9) +/- 0.1 (0.12-5.4) P < 0.0001. The median mononuclear cell count (MNC) per kg harvested was 0.67 x 10(8) +/- 0.05 (0.18-2.0) vs an infused cell number of 1.3 x 10(8) MNC/kg +/- 0.1 (0.6-33.6) P < 0. 0001. The CD34+ cells harvested were 2.8 x 10(6)/kg +/- 0.1 (0.25-10.2) vs an infused number of 6.0 x 10(6)/kg +/- 0.5 (0.84-31.0) P < 0.0001. The viability before and after processing was 99%. Red cell salvage performed in a semi-automated closed system is safe and reduces the risk of post-bone marrow harvest anemia in pediatric donors, decreases the volume infused into the donor and enriches the mononuclear and CD34+ cell population, without affecting hematopoietic reconstitution.

Outcomes of unrelated cord blood transplants and allogeneic-related hematopoietic stem cell transplants in children with high-risk acute lymphocytic leukemia.

Acute lymphocytic leukemia (ALL) is a common indication for hematopoietic stem cell transplantation (HSCT) in children. Use of unrelated cord blood (UCB) has become increasingly popular as a stem cell source, given the rapid availability and decreased GVHD potential. Publications describing outcomes of children with leukemia who underwent UCB transplants have compared them to those having received unrelated donor marrow transplants. Results are similar. We compared our outcomes using UCB vs allogeneic-related hematopoietic stem cells in pediatric ALL patients since 1992. A total of 49 patients were analyzed. All patients were either in CR1 with high-risk features (n=21) or in CR2 (n=28) with initial remission less than 36 months. Patients received myeloablation with fractionated total body irradiation, cyclophosphamide, and etoposide and GVHD prophylaxis with cyclosporine and methotrexate. Antithymocyte globulin was added for UCB recipients to address the HLA differences. In all, 23 patients underwent allogeneic -related HSCT and 26 underwent UCB transplantation. Other than increased time to engraftment for UCB recipients, results are equivalent. The 3-year overall survival is 64% and 3-year event-free survival is 60% for both groups. Rates of GVHD and transplant-related mortality are also equivalent. UCB is a reasonable option for children with ALL who are referred for HSCT.

Cytokine-mobilized allogeneic peripheral blood stem cell transplants in children result in rapid engraftment and a high incidence of chronic GVHD.

Between October 1995 and October 1998, 24 children aged 9 months to 17 years (median 11 years) underwent cytokine-mobilized allogeneic peripheral blood stem cell (PBSC) transplantation for treatment of hematological disorders. All of the transplants were the first allogeneic transplant for the recipient. Twenty patients were transplanted for hematological malignancies (ALL = 8, AML = 6, CML = 4, MDS = 2) and four patients were transplanted for non-malignant disease (thalassemia major = 2, Wiskott-Aldrich syndrome = 1, Kostmann's syndrome = 1). Nineteen donors were HLA-identical siblings, four were HLA-matched or single antigen mismatched parents, and one was a syngeneic transplant. Donors aged 8 to 38 years (median 15 years, 14 donors <18 years) received G-CSF 10 microg/kg/day subcutaneously beginning 4 days before PBSC collection and were submitted to one to three leukapheresis collections. The median CD34+ cell yield was 7.8 x 106 cells/kg recipient body weight. All patients achieved an ANC >0.5 x 109/l after a median of 13 days (range 10-21). Twenty-three patients eventually achieved platelet transfusion independence. One patient died on day 63 without ever achieving platelet transfusion independence. Four patients received platelet transfusions to maintain a platelet count well above 20 x 109/l due to bleeding complications. Of the 19 evaluable patients, the median time to a non-transfused platelet count of 20 x 109/l was 12 days (range 0-44). Ten of 23 at-risk patients developed acute GVHD grades II to IV, with grades III to IV in four patients. Twelve of 19 patients followed for at least 100 days have developed chronic GVHD (extensive = 2, limited = 10) with an actuarial risk of chronic GVHD of 75% at 1 year. The Kaplan-Meier estimate of event-free survival is 65% at 2 years. Four patients died (GVHD = 3, VOD = 1), three patients relapsed, and one patient with thalassemia major had a late graft failure with autologous recovery. Based upon our experience, allogeneic PBSCT is safe for both pediatric donors and recipients and engraftment of neutrophils and platelets is rapid. Bone Marrow Transplantation (2000) 25, 13-18.

Correction of neutropenia and hypogammaglobulinemia in X-linked hyper-IgM syndrome by allogeneic bone marrow transplantation.

X-linked hyper-IgM (X-HIM) syndrome is a primary immunodeficiency disease characterized by defects in both cellular and humoral immunity. X-HIM is caused by mutations in the gene for CD40 ligand (CD40L), a T cell membrane protein that mediates T cell-dependent immune functions. We report the case of a 6-year-old male with X-HIM due to an intronic mutation resulting in aberrant CD40L RNA splicing and absence of detectable CD40L protein. The patient had a history of multiple infectious complications and chronic neutropenia requiring treatment with recombinant granulocyte colony-stimulating factor, and underwent allogeneic bone marrow transplantation from an HLA-matched sibling donor. Following successful engraftment, T cell CD40L expression and immunoglobulin isotype switching were reconstituted and neutropenia resolved. Allogeneic bone marrow transplantation can correct neutropenia and reconstitute immune function in X-HIM.

Treatment of congenital erythropoietic porphyria in children by allogeneic stem cell transplantation: a case report and review of the literature.

Congenital erythropoietic porphyria (CEP) is a rare autosomal recessive disorder of porphyrin metabolism in which the genetic defect is the deficiency of uroporphyrinogen III cosynthase (UIIIC). Deficiency of this enzyme results in an accumulation of high amounts of uroporphyrin I in all tissues leading to hemolytic anemia, splenomegaly, erythrodontia, bone fragility, exquisite photosensitivity and mutilating skin lesions. We describe the case of a 23-month-old boy who was cured of his CEP by a matched-sibling allogeneic bone marrow transplant, and review the published clinical experience regarding transplantation in this disease. He is alive and disease-free 15 months post transplant. All of his disease manifestations except for the erythrodontia have resolved. His UIIIC level and stool and erythrocyte porphyrin metabolites have almost completely corrected. He is the sixth child reported to be cured of this disease by stem cell transplantation, five cases being long-term survivors. If patients with this disease have an HLA-matched sibling, then stem cell transplantation should be strongly considered because this is currently the only known curative therapy.

Evaluation of mixed hematopoietic chimerism in pediatric patients with leukemia after allogeneic stem cell transplantation by quantitative PCR analysis of variable number of tandem repeat and testis determination gene.

In order to monitor the clinical outcome of pediatric patients with leukemia following allogeneic hematopoietic transplantation, tests of variable number of tandem repeat (VNTR) and sex determination by quantitative polymerase chain reaction (PCR) were performed. PCR results combined with the blast counts from 21 leukemia patients were analyzed. Complete chimerism (100% donor cells) was found in 15 cases with remission, and incomplete chimerism in six cases with relapse. In the majority of cases, complete chimerism was always associated with no detectable blasts, while blasts were often detected in association with incomplete chimerism. There is significant correlation (P<0.0001) between the percentage of donor DNA and blast percentage in these patients. Early detection of incomplete chimerism may therefore predict a poor prognosis. In one patient (case 15), a differing percentage of donor DNA was observed between samples of bone marrow and peripheral blood collected on the same day. This may be due to the fact that allogeneic stem cells proliferate at different rates depending on their environment (bone marrow or peripheral blood). In addition, 100% donor cells found in the peripheral blood may not reflect the number of cells in the bone marrow. In case 17, asynchronous engraftment of donor cells was present between the white and red blood cell lineages, indicating that the degree of chimerism may not be the same in all cell lineages. At the time of this report, the significance of this observation is unknown and needs further investigation.

Haploidentical related umbilical cord blood stem cell transplant in a child with acute non-lymphocytic leukemia.

Umbilical cord blood stem cells (UCBSC) were used to reconstitute hematopoiesis following myeloablative therapy in a 13-month-old infant with acute nonlymphocytic leukemia (ANLL):FAB-M5 who had failed to sustain a chemotherapeutic remission. The patient's mother was 18 weeks pregnant with her second child at the time of diagnosis. Amniocentesis revealed that the fetus was HLA-haploidentical with the patient at the paternally inherited allele. The umbilical cord blood was harvested and processed by Ficoll centrifugation with 100% recovery of 5 x 10(7) mononuclear cells/kg and then cryopreserved. Two weeks after collection the cells were thawed and then infused into the patient following conditioning with total body irradiation, cyclophosphamide, and etoposide. Graft-versus-host-disease (GVHD) prophylaxis consisted of cyclosporine and methotrexate. The patient experienced clinical grade I GVHD consisting of skin involvement only that resolved within 2 weeks following the addition of corticosteroids. Engraftment was achieved with an absolute neutrophil count (ANC) above 0.5 x 10(9)/l on day 16, a platelet count above 50 x 10(9)/l on day 56, platelet transfusion independence on day 32 and red blood cell transfusion independence after day 44. Three months following transplantation restriction fragment length polymorphism (RFLP) revealed no discernible difference between the donor and the recipient. The patient remains in remission without evidence of GVHD 23 months post-transplant.

Detection of EBV DNA in the cord blood donor for a patient developing Epstein-Barr virus-associated lymphoproliferative disorder following mismatched unrelated umbilical cord blood transplantation.

Epstein-Barr virus-associated post-transplant lymphoproliferative disorder (PTLD) has been well described as a complication following allogeneic stem cell transplantation but has only recently been reported following umbilical cord blood (UCB) transplant. We report the case of a child transplanted with unrelated mismatched UCB for juvenile chronic myelogenous leukemia (JCML) who developed EBV-associated PTLD, which was confirmed pathologically, 139 days following stem cell infusion. There was no clinical response to reduction of immune suppression, high-dose acyclovir, or alpha interferon. The patient died 160 days after transplantation. EBV was detected by polymerase chain reaction in the cord blood unit used for transplantation. This case demonstrates that EBV-associated PTLD can occur following mismatched unrelated UCB transplant and may be related to transmission of EBV infection by donor lymphocytes.

Treatment of poor-risk neuroblastoma patients with high-dose chemotherapy and autologous peripheral stem cell rescue.

A single institutional pilot study was conducted in which 12 poor-risk neuroblastoma (NB) patients were uniformly treated with multi-agent induction chemotherapy followed by myeloablative consolidation chemotherapy and unpurged peripheral blood stem cell (PBSC) rescue. In addition to using standard criteria for evaluating response to induction chemotherapy, tumor cell contamination of the peripheral blood and/or bone marrow was analyzed in seven patients by immunocytology using a panel of five anti-NB monoclonal antibodies. Seven patients had morphologic evidence of bone marrow disease at the time of diagnosis, and two additional patients had tumor cells detected in bone marrow samples by immunocytology prior to the second cycle of chemotherapy. After three cycles of chemotherapy, two of the 12 patients continued to have evidence of bone marrow disease. Samples from 29 PBSC harvests collected from nine patients were also analyzed for the presence of contaminating tumor cells by immunocytology. In each case, the stem cells were found to be free of tumor. Eleven of the 12 patients underwent myeloablative therapy and PBSC rescue; five patients remain alive without disease progression, 28+ to 53+ months from diagnosis, and six patients have developed recurrent disease. We conclude that PBSCs can be successfully harvested from children with NB, and used for hematopoietic reconstitution following myeloablative chemotherapy. However, more effective therapy for poor-risk NB patients is still urgently needed.

Outpatient total body irradiation prior to bone marrow transplantation in pediatric patients: a feasibility analysis.

Outpatient total body irradiation (TBI) prior to bone marrow transplantation has been accomplished in a total of 68 pediatric patients. The TBI regimen was fractionated with a total dose of 12 Gy in eight fractions twice daily. Antiemetic therapy consisted of oral ondansetron three times daily throughout the TBI course. Eight patients experienced mild nausea without vomiting, and four patients experienced mild nausea and vomiting. One patient required intravenous hydration after severe nausea and vomiting. Another patient experienced intractable diarrhea and dehydration which required inpatient management. Outpatient TBI prior to bone marrow transplantation is feasible in pediatric patients.