Extended induction chemotherapy does not improve the outcome for high-risk neuroblastoma patients: results of the randomized open-label GPOH trial NB2004-HR.

BACKGROUND: Long-term survival of high-risk neuroblastoma patients is still below 50% despite intensive multimodal treatment. This trial aimed to address whether the addition of two topotecan-containing chemotherapy courses compared to standard induction therapy improves event-free survival (EFS) of these patients. PATIENTS AND METHODS: An open-label, multicenter, prospective randomized controlled trial was carried out at 58 hospitals in Germany and Switzerland. Patients aged 1-21 years with stage 4 neuroblastoma and patients aged 6 months to 21 years with MYCN-amplified tumors were eligible. The primary endpoint was EFS. Patients were randomly assigned to standard induction therapy with six chemotherapy courses or to experimental induction chemotherapy starting with two additional courses of topotecan, cyclophosphamide, and etoposide followed by standard induction chemotherapy (eight courses in total). After induction chemotherapy, all patients received high-dose chemotherapy with autologous hematopoietic stem cell rescue and isotretinoin for consolidation. Radiotherapy was applied to patients with active tumors at the end of induction chemotherapy. RESULTS: Of 536 patients enrolled in the trial, 422 were randomly assigned to the control arm (n = 211) and the experimental arm (n = 211); the median follow-up time was 3.32 years (interquartile range 1.65-5.92). At data lock, the 3-year EFS of experimental and control patients was 34% and 32% [95% confidence Interval (CI) 28% to 40% and 26% to 38%; P = 0.258], respectively. Similarly, the 3-year overall survival of the patients did not differ [54% and 48% (95% CI 46% to 62% and 40% to 56%), respectively; P = 0.558]. The response to induction chemotherapy was not different between the arms. The median number of non-fatal toxicities per patient was higher in the experimental group while the median number of toxicities per chemotherapy course was not different. CONCLUSION: While the burden for the patients was increased by prolonging the induction chemotherapy and the toxicity, the addition of two topotecan-containing chemotherapy courses did not improve the EFS of high-risk neuroblastoma patients and thus cannot be recommended. CLINICAL TRIALS. GOV NUMBER: NCT number 03042429.

Randomised Introduction of 2-CDA as Intensification during Consolidation for Children with High-risk AML--results from Study AML-BFM 2004.

BACKGROUND: The outcome in children and adolescents with high-risk (HR) acute myeloid leukemia (AML) is still unsatisfactory. Therefore, in study AML-BFM 2004 we aimed to improve outcome of HR-patients by adding moderately dosed 2-Chloro-2-Deoxyadenosine (2-CDA) to the respective consolidation treatment backbone without increasing toxicity. The aim was to improve prognosis especially in FAB M4/M5/MLL patients, who represent the largest subgroup of HR patients. PATIENTS AND METHODS: In total, 343 children and adolescents with HR-AML were randomized to receive or not 2-CDA (6 mg/m²/d, days 1, 3) in combination with cytarabine/idarubicine (AI=500 mg/m² cytarabine 5 days continuous infusion plus 7 mg/m²/d idarubicin, days 3 and 5). RESULTS: RESULTS for patients of the AI/2-CDA arm (n=168) vs. the AI-arm (n=175) were similar: 5-year overall survival 68±4 vs. 72±4%, plogrank=0.38, event-free survival 53±4 vs. 49±4%, plogrank=0.77; cumulative incidence of relapse at 5 years: 35±4 vs. 37±4%, p(Gray)=0.89. RESULTS in patients with MLL rearrangement or FAB M4/M5 were also similar in the treatment groups. In addition, toxicities did not differ between the two arms. CONCLUSION: We conclude that additional, moderate dose 2-CDA does not improve prognosis in HR-patients when given during consolidation treatment. Its effect might be too low in this multidrug regimen, where the strongest effects are achieved during induction, or the chosen dose of 2-CDA might have been too low.

Consensus of German transplant centers on hematopoietic stem cell transplantation in Fanconi anemia.

Allogeneic hematopoietic stem cell transplantation (HSCT) is currently the only curative therapy for the severe hematopoietic complications associated with Fanconi anemia (FA). In Germany, it is estimated that 10-15 transplants are performed annually for FA. However, because FA is a DNA repair disorder, standard conditioning regimens confer a high risk of excessive regimen-related toxicities and mortality, and reduced intensity regimens are linked with graft failure in some FA patients. Moreover, development of graft-versus-host disease is a major contributing factor for secondary solid tumors. The relative rarity of the disorder limits HSCT experience at any single center. Consensus meetings were convened to develop a national approach for HSCT in FA. This manuscript outlines current experience and knowledge about HSCT in FA and, based on this analysis, general recommendations reached at these meetings.

Key treatment questions in childhood acute lymphoblastic leukemia: results in 5 consecutive trials performed by the ALL-BFM study group from 1981 to 2000.

Between 1981 and 2000, 6 609 children (<18 years of age) were treated in 5 consecutive trials of the Berlin-Frankfurt-Münster (BFM) study group for childhood acute lymphoblastic leukemia (ALL). Patients were treated in up to 82 centers in Germany, Austria, and Switzerland. Probability of 10-year event-free survival (survival) improved from 65% (77%) in study ALL-BFM 81-78% (85%) in ALL-BFM 95. In parallel to relapse reduction, major efforts focused on reducing acute and late toxicity through advanced risk adaptation of treatment. The major findings derived from these ALL-BFM trials were as follows: 1) preventive cranial radiotherapy could be safely reduced to 12 Gy in T-ALL and high-risk ALL patients and eliminated in non-high-risk non-T-ALL patients, if it was replaced by high-dose and intrathecal methotrexate; 2) omission of delayed reintensification severely impaired outcome of low-risk patients; 3) 6 months less maintenance therapy caused an increase in systemic relapses; 4) slow response to an initial 7-day prednisone window was identified as adverse prognostic factor; 5) condensed induction therapy resulted in a significant improvement of outcome; 6) the daunorubicin dose in induction could be safely reduced in low-risk patients; 7) intensification of consolidation/reintensification treatment led to considerable improvement of outcome in high-risk patients.

Allogeneic stem cell transplantation for pediatric and adolescent patients with CML: results from the prospective trial CML-paed I.

PURPOSE: Stem cell transplantation (SCT) can definitely cure chronic myeloid leukemia (CML), a rare disease in childhood. We prospectively evaluated the results of early SCT in pediatric CML after standardized pretreatment with hydroxyurea+/-interferon. PATIENTS AND METHODS: Between 1995 and 2004, 200 children (median age: 12.4 years) were enrolled and stratified: given the availability of an HLA-matched related donor (MRD), SCT was scheduled within 6 months and otherwise from an unrelated donor (UD) within 12 months following diagnosis. RESULTS: 176 patients underwent SCT; from MRD within median 4 months and from UD within median 11 months after diagnosis. At SCT, 158 patients were in chronic phase (CP1 or CP2), 9 patients were in accelerated phase and 9 patients were in blast crisis (BC). The conditioning regimen - total body irradiation or busulfan - exerted no different impact on overall survival (OS). Probability of OS at 5 years was 87+/-11% if grafted from a sibling (n=41), 52+/-9% from matched UD (MUD, n=71), and 45+/-16% from mismatched donors (MMD, n=55), respectively. A trend for better OS in CP1 was observed if SCT was performed within 6 months (n=49; 74+/-9%), compared to 7-12 months (n=52; 62+/-15%), and >12 months (n=43; 62+/-17%) after diagnosis, respectively (p=0.157). Probability of relapse at 5 years was 20+/-12%. Transplant-related mortality and graft-versus-host disease mainly contributed to the inferior outcome in UD and HLA-mismatched SCT. CONCLUSION: These data from the first prospective trial on CML restricted to children and adolescents might be considered for decision making when balancing the risks of SCT against the increasing use of imatinib as upfront treatment for CML.

Reduced intensity conditioning in unrelated donor transplantation for refractory cytopenia in childhood.

Myelodysplastic syndromes (MDS) are a heterogenous group of acquired hematopoietic stem cell disorders. Refractory cytopenia (RC) is the most common subtype of childhood MDS and hematopoietic stem cell transplantation (HSCT) is the only curative treatment. HSCT following a myeloablative preparative regimen is associated with a low probability of relapse and considerable transplant-related mortality. In the present European Working Groups of MDS pilot study, we investigated whether a reduced intensity conditioning regimen (RIC) is able to offer reduced toxicity without increased rates of graft failure or relapse. Nineteen children with RC were transplanted from an unrelated donor following RIC consisting of fludarabine, thiotepa and anti-thymocyte globulin. Three patients experienced graft failure. Neutrophil and platelet engraftment occurred at a median time of 23 and 30 days, respectively. Cumulative incidence of grade II-IV and grade III and IV acute graft-versus-host disease (GVHD) was 0.48 and 0.13, respectively; three patients developed extensive chronic GVHD. Although infections were the predominant complications, only one patient with extensive chronic GVHD died from infectious complications. Overall and event-free survival at 3 years were 0.84 and 0.74, respectively. In conclusion, our results were comparable to those of patients treated with myeloablative HSCT. Long-term follow-up is needed to demonstrate the expected reduction in long-term sequelae.

[Systemic therapy in children and adolescents]. / Systemtherapie bei Kindern und Jugendlichen.

Urologic malignancies in childhood and adolescence are mainly nephroblastomas, neuroblastomas, soft tissue sarcomas, and germ cell tumors. National and supranational treatment studies are the standard of care for pediatric cancer in Germany; they yield 5-year survival rates of almost 90% for nephroblastoma and germ cell tumors and 60% for neuroblastoma (all stages) and rhabdomyosarcoma. The principles of antineoplastic therapy are the same as in adult cancer medicine; the drugs used depend upon the disease. In a multimodal treatment strategy, the role of chemotherapy as well as that of surgery and radiotherapy can differ, as is described for nephroblastoma, infant neuroblastoma, and stage 4 neuroblastoma.

Genotype-outcome correlations in pediatric AML: the impact of a monosomal karyotype in trial AML-BFM 2004.

We conducted a cytogenetic analysis of 642 children with de novo acute myeloid leukemia (AML) treated on the AML-Berlin-Frankfurt-Münster (BFM) 04 protocol to determine the prognostic value of specific chromosomal aberrations including monosomal (MK+), complex (CK+) and hypodiploid (HK+) karyotypes, individually and in combination. Multivariate regression analysis identified in particular MK+ (n=22) as a new independent risk factor for poor event-free survival (EFS 23±9% vs 53±2% for all other patients, P=0.0003), even after exclusion of four patients with monosomy 7 (EFS 28±11%, P=0.0081). CK+ patients without MK had a better prognosis (n=47, EFS 47±8%, P=0.46) than those with MK+ (n=12, EFS 25±13%, P=0.024). HK+ (n=37, EFS 44±8% for total cohort, P=0.3) influenced outcome only when t(8;21) patients were excluded (remaining n=16, EFS 9±8%, P<0.0001). An extremely poor outcome was observed for MK+/HK+ patients (n=10, EFS 10±10%, P<0.0001). Finally, isolated trisomy 8 was also associated with low EFS (n=16, EFS 25±11%, P=0.0091). In conclusion, monosomal karyotype is a strong and independent predictor for high-risk pediatric AML. In addition, isolated trisomy 8 and hypodiploidy without t(8;21) coincide with dismal outcome. These results have important implications for risk stratification and should be further validated in independent pediatric cohorts.

Vaccination to improve the persistence of CD19CAR gene-modified T cells in relapsed pediatric acute lymphoblastic leukemia.

Trials with second generation CD19 chimeric antigen receptors (CAR) T-cells report unprecedented responses but are associated with risk of cytokine release syndrome (CRS). Instead, we studied the use of donor Epstein-Barr virus-specific T-cells (EBV CTL) transduced with a first generation CD19CAR, relying on the endogenous T-cell receptor for proliferation. We conducted a multi-center phase I/II study of donor CD19CAR transduced EBV CTL in pediatric acute lymphoblastic leukaemia (ALL). Patients were eligible pre-emptively if they developed molecular relapse (>5 × 10-4) post first stem cell transplant (SCT), or prophylactically post second SCT. An initial cohort showed poor expansion/persistence. We therefore investigated EBV-directed vaccination to enhance expansion/persistence. Eleven patients were treated. No CRS, neurotoxicity or graft versus host disease (GVHD) was observed. At 1 month, 5 patients were in CR (4 continuing, 1 de novo), 1 PR, 3 had stable disease and 3 no response. At a median follow-up of 12 months, 10 of 11 have relapsed, 2 are alive with disease and 1 alive in CR 3 years. Although CD19CAR CTL expansion was poor, persistence was enhanced by vaccination. Median persistence was 0 (range: 0-28) days without vaccination compared to 56 (range: 0-221) days with vaccination (P=0.06). This study demonstrates the feasibility of multi-center studies of CAR T cell therapy and the potential for enhancing persistence with vaccination.

Donor leukocyte infusion after hematopoietic stem cell transplantation in patients with juvenile myelomonocytic leukemia.

Juvenile myelomonocytic leukemia (JMML) is a clonal myeloproliferative disorder of early childhood. In all, 21 patients with JMML who received donor leukocyte infusion (DLI) after allogeneic hematopoietic stem cell transplantation (HSCT) for either mixed chimerism (MC, n=7) or relapse (n=14) were studied. Six patients had been transplanted from an HLA-matched sibling and 15 from other donors. Six of the 21 patients (MC: 3/7 patients; relapse: 3/14 patients) responded to DLI. Response rate was significantly higher in patients receiving a higher total T-cell dose (> or =1 x 10(7)/kg) and in patients with an abnormal karyotype. None of the six patients receiving DLI from a matched sibling responded. Response was observed in five of six patients who did and in one of 15 children who did not develop acute graft-versus-host disease following DLI (P=0.01). The overall outcome was poor even for the responders. Only one of the responders is alive in remission, two relapsed, and three died of complications. In conclusion, this study shows that some cases of JMML may be sensitive to DLI, this providing evidence for a graft-versus-leukemia effect in JMML. Infusion of a high number of T cells, strategies to reduce toxicity, and cytoreduction prior to DLI may improve the results.

Primary mediastinal germ cell tumors in children and adolescents: results of the German cooperative protocols MAKEI 83/86, 89, and 96.

PURPOSE: To evaluate children and adolescents with primary mediastinal teratoma and malignant germ cell tumors (GCTs). PATIENTS AND METHODS: Forty-seven patients from the German nontesticular GCT studies were analyzed (median age, 2.5 years; range, neonate to 17 years). Teratoma (n = 21) were resected, and no adjuvant treatment was given. Malignant GCTs (n = 26) were treated with cisplatin-based chemotherapy and resection. Three of 26 patients underwent radiotherapy. RESULTS: In all patients with teratoma, tumor markers were normal. Surgery of teratoma was complete in 17 of 21 patients and microscopically incomplete in four of 21 patients, and we observed no relapse after a median follow-up of 29 months. In 23 of 26 patients with malignant GCTs, alpha-fetoprotein and/or beta-human chorionic gonadotropin were elevated. Twelve of 26 patients received adjuvant chemotherapy after initial resection, which was complete in six of 12 patients, whereas delayed resection after preoperative chemotherapy was complete in 10 of 11 patients (P =.03). Four of six patients underwent second-look thoracotomy after incomplete primary surgery. Three of 26 patients did not undergo tumor resection. The final completeness of resection was the strongest prognostic indicator (event-free survival ¿EFS, 0.94 +/- 0.06 v 0.42 +/- 0.33; P <.002). Local stage and distant metastases were not prognostically significant at the.05 level. For all malignant GCTs, the 5-year survival rate was 0.87 +/- 0.05 (median follow-up, 51 months), with an EFS of 0.83 +/- 0.05. CONCLUSION: The prognosis of mediastinal teratoma is excellent after complete or microscopically incomplete resection. In children with malignant GCT, the prognosis is favorable with a therapeutic strategy of delayed resection after preoperative chemotherapy. In most children, the diagnosis can be based on elevated tumor markers and imaging. Biopsy is indicated in nonsecreting GCT.

Multivariate analysis of risk factors in stage 4 neuroblastoma patients over the age of one year treated with megatherapy and stem-cell transplantation: a report from the European Bone Marrow Transplantation Solid Tumor Registry.

PURPOSE: The European Bone Marrow Transplantation (EBMT) Solid Tumor Registry (STR) contains detailed information on children with advanced neuroblastoma who, after standard-dose induction chemotherapy and surgery, received myeloablative megatherapy (MGT) followed by stem-cell transplantation (SCT). This data base was analyzed to identify factors that predict event-free survival (EFS). PATIENTS AND METHODS: Eligibility criteria were stage IV neuroblastoma, age over 1 year at diagnosis, and no relapse before MGT/SCT. Between February 1978 and July 1992, 549 patients were registered by 36 European transplant centers. The median age at diagnosis was 36 months (range, 13 to 216 months) and the male-female ratio was 1:45. Before MGT, 157 patients were in complete remission (CR), 156 in very good partial remission (VGPR), and 208 in partial remission (PR), whereas 24 had had only a minor response (MR). One hundred ten of 546 patients had undergone two successive MGT procedures. The median observation time was 60 months (range, 12 to 187 months). RESULTS: Actuarial EFS is 26% at 5 years. Multivariate analysis by the Cox proportional hazards regression model included 529 patients with complete data sets. After adjustment for treatment duration before MGT and double MGT procedures, two adverse, independent risk factors that influenced EFS were identified: (1) persisting skeletal lesions before MGT as defined by technetium (99TC) scans and/or meta-iodobenzylguanidine (mIBG) scans (P = .004) and (2) persisting bone marrow involvement before MGT (P = .03). CONCLUSION: After induction treatment, persisting skeletal disease as defined above and persisting bone marrow involvement may be predictive of a particularly poor outcome. Physicians may consider this an additional important tool to decide the patient's management.

Allogeneic bone marrow transplantation for chronic myelomonocytic leukemia in childhood: a report from the European Working Group on Myelodysplastic Syndrome in Childhood.

PURPOSE: To evaluate the role of allogeneic bone marrow transplantation (BMT) in children with chronic myelomonocytic leukemia (CMML). PATIENTS AND METHODS: Forty-three children with CMML given BMT and reported to the European Working Group on Myelodysplastic Syndrome in Childhood (EWOG-MDS) data base were evaluated. In 25 cases, the donor was a human leukocyte antigen (HLA)-identical or a one-antigen-disparate relative, in four cases a mismatched family donor, and in 14 a matched unrelated donor (MUD). Conditioning regimens consisted of total-body irradiation (TBI) and chemotherapy in 22 patients, whereas busulfan (Bu) with other cytotoxic drugs was used in the remaining patients. RESULTS: Six of 43 patients (14%), five of whom received transplants from alternative donors, failed to engraft. There was a significant difference in the incidences of chronic graft-versus-host disease (GVHD) between children transplanted from compatible/one-antigen-mismatched relatives and from alternative donors (23% and 87%, respectively; P < .005). Probabilities of transplant-related mortality for children given BMT from HLA-identical/one-antigen-disparate relatives or from MUD/ mismatched relatives were 9% and 46%, respectively. The probability of relapse for the entire group was 58%, whereas the 5-year event-free survival (EFS) rate was 31%. The EFS rate for children given BMT from an HLA-identical sibling or one-antigen-disparate relative was 38%. In this latter group, patients who received Bu had a better EFS compared with those given TBI (62% v 11%, P < .01). CONCLUSION: Children with CMML and an HLA-compatible relative should be transplanted as early as possible. Improvement of donor selection, GVHD prophylaxis, and supportive care are needed to ameliorate results of BMT from alternative donors.

High-dose corticosteroid therapy for bronchiolitis obliterans after bone marrow transplantation in children.

Bronchiolitis obliterans (BO) is a rare but serious complication of paediatric allogenic bone marrow transplantation (BMT). Currently, there is no clear evidence that therapeutic interventions have a positive impact on the course of the disease. We here report our experience with high-dose pulse methylprednisolone therapy in children after BMT. Nine patients fulfilling clinical and radiologic signs of BO were included in this analysis. The total amount of treatment cycles with pulse methylprednisolone therapy ranged from 1 to 6 cycles (median four cycles). Oxygen saturation increased significantly with normalization of oxygen saturation at the end of therapy in all individuals. Normal oxygen saturation was maintained in all but one patient during follow-up (mean follow-up period 42 {plus/minus} 20 months, range 19-67 months). Forced expiratory volume in 1 s (FEV1) was within the normal range prior BMT and significantly diminished at the time of BO diagnosis. Treatment led to stabilization of lung function, with a significant improvement of FEV1 after 2 months. In all, 7/9 patients remained in clinically stable condition without further deterioration of lung function during follow-up. These data would suggest that anti-inflammatory therapy may be a valuable treatment option in paediatric patients with bronchiolitis obliterans after BMT.

1070 myeloablative megatherapy procedures followed by stem cell rescue for neuroblastoma: 17 years of European experience and conclusions. European Group for Blood and Marrow Transplant Registry Solid Tumour Working Party.

1070 myeloablative procedures followed by stem cell rescue for neuroblastoma are reviewed. These 1070 procedures are part of the European Group for Blood and Marrow Transplant (EBMTG) registry from the last 17 years (in 4536 patients). In 1070 neuroblastoma patients, survival at 2 years was 49%, at 5 years, 33% and relapses were observed as late as 7 years post-BMT (bone marrow transplant). However, 5-year survivors after megatherapy with BMT for stage 4 disease do have an 80% chance of becoming a long-term survivor. When BMT had been used in first complete response (CR1) no salvage was possible, whereas 15% survivors may be seen if BMT is used for the first time at relapse. Infants with stage 4 neuroblastoma had a 17% toxic death rate and indication in this group is exceptional and not recommended. In a matched cohort (17 allogeneic and 34 autologous), autologous stem cell rescue (SCR) was shown to be at least equal to allogeneic SCR. Multivariate analysis of clinical prognostic factors in children with stage 4 disease over 1 year showed that event-free survival was mainly influenced by two adverse factors before the megatherapy procedure: persisting skeleton lesions (99Tc and/or mIBG scan positive) as well as persisting bone marrow (BM) involvement.

Long-term results and risk profiles of patients in five consecutive trials (1979-1997) with stage 4 neuroblastoma over 1 year of age.

During the last two decades new diagnostic and therapeutic tools have been utilized to improve the poor survival chances of children with stage 4 neuroblastoma. This study reviews the risk profiles and the long-term outcome of patients from five consecutive German neuroblastoma trials. A total of 96% of all German patients registered at the German childhood cancer registry with neuroblastoma stage 4 over 1 year of age at diagnosis entered one of the trials during 1979-2001. Eight hundred and twenty-eight consecutive children were analyzed retrospectively. In spite of having significantly improved diagnostic tools like bone marrow superstaging and mIBG scintigraphy the stage 4 incidence did not increase after reaching completeness of the registry (5.4 cases/100,000 children at 1-14 years of age; P=0.52). The distribution of the primary tumors and of metastases was constant over the periods. The amount of bone marrow infiltration did not change with time. The risk factors lactate dehydrogenase, ferritin and MYCN, and the clinical risk groups 4A, 4B, 4C also remained constant over the trials with a few exceptions for NB97. The 5-year event free survival increased from 0.01+/-0.01 (NB79) to 0.14+/-0.03 (NB85), 0.16+/-0.04 (NB82), 0.27+/-0.02 (NB90), and 0.33+/-0.04 (NB97). The overall survival rates improved similarly from 0.04 (NB79) to 0.44 (NB97). In conclusion, the improved survival was associated with better treatment and not caused by lower risk profiles in stage 4 neuroblastoma patients.

Recurrent disseminated retinoblastoma in a 7-year-old girl treated successfully by high-dose chemotherapy and CD34-selected autologous peripheral blood stem cell transplantation.

A localized retinoblastoma of the left eye in a 7-year-old girl, was treated by enucleation. She received no additional therapy. Four months later, metastases of retinoblastoma in the lymph nodes, bone and bone marrow were diagnosed. Relapse chemotherapy consisting of three courses of vincristine, cyclophosphamide, etoposide and carboplatin led to a second complete remission. Subsequent high-dose chemotherapy with thiotepa, etoposide and carboplatin and autologous stem cell transplantation with CD34-selected stem cells were successful, with no adverse effects. No radiotherapy was given and the girl remains in continuous second remission with a follow-up of more than 4 years.

Allogeneic CD34+ -selected peripheral stem cell transplantation from parental donors in children with non-malignant diseases.

Allogeneic peripheral stem cell transplantation in six children with non-malignant hematologic or metabolic diseases which are eventually fatal was carried out with parental donors. Given three to five HLA mismatches, all grafts underwent CD34+ cell selection as graft-versus-host prophylaxis. The patients received median doses of 16.7 x 10(6) CD34+ cells/kg and 1.2 x 10(4) CD3+ cells/kg. All transplants engrafted. Neutrophils >0.5/nl were reached on day 11 (9-19) and platelets >50/nl on day 13 (10-25). Acute GVHD responding to steriods occured in three of six patients; it was restricted to the skin and overall did not exceed grade I. Two patients died of viral infections and four are alive with stable blood counts for 13, 15, 25 and 26 months. For children with non-malignant diseases which will eventually be fatal and which can be cured or ameliorated by allogeneic BMT, CD34+-selected stem cell transplants from mismatched or even haploidentical parents can be used if no other suitable donor is available. With high CD34+ cell doses and low CD3+ cell numbers, engraftment and avoidance of acute GVHD can be expected. Infections after transplantation remain the primary threat to survival.

S-L 11.14: a monoclonal antibody recognizing neuroectodermal tumors with possible value for bone marrow purging before autograft.

A new monoclonal antibody (S-L 11.14) raised against small cell lung cancer reacted with all but one neuroblastoma tumor cell sample tested and was relatively specific for such cells within the bone marrow. The ability of S-L 11.14 to eliminate neuroblastoma cells from the bone marrow with an immunomagnetic purging method was evaluated in an experimental model using the LAN.1 and SKNBE neuroblastoma cell lines as targets. Residual malignant cells after the purging procedure were quantified by the Hoechst staining method. The use of S-L 11.14 as a single reagent resulted in a 3-log elimination of malignant cells, a depletion equal to that obtained with a cocktail of five monoclonal antibodies currently used in clinical trials. The addition of the S-L 11.14 antibody to this cocktail did not enhance depletion.

Transplantation of CD34-enriched peripheral stem cells from an HLA-haplotype mismatched donor to a patient with severe aplastic anemia.

A 14-year-old girl developed very severe aplastic anemia unresponsive to steroids, cyclosporine, ATG and filgrastim. She experienced repeated bacterial infections, hypermenorrhagia and epistaxis and received numerous transfusions. Lacking a matched family or unrelated donor, she was transplanted 6 months after diagnosis with CD34+ cell-enriched peripheral stem cells from her HLA-haploidentical uncle. Conditioning included fludarabine, cyclophosphamide, 800 cGy TLI and OKT3. Prompt and sustained trilineage engraftment occurred. Acute GVHD grade 1 and herpes esophagitis were successfully treated. Eight months after grafting she was well with stable hematopoiesis. She then succumbed to fulminant hepatic failure due to adenovirus infection.