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Background: Flow cytometric analysis of minimal residual disease (MRD) depends on detecting phenotypically abnormal populations. However, little is known about how phenotypic shifts between diagnosis and relapse affect MRD detection in childhood acute lymphoid leukemia (ALL)., Methods: We compared diagnostic and relapse bone marrow specimens in 42 children with precursor B-ALL studied with the two-tube panel CD19-APC/CD45-PerCP/CD10-PE/CD20-FITC and CD19-APC/CD45-PerCP/CD9-PE/CD34-FITC., Results: At least 29 cases had phenotypic shifts of intensity or coefficient of variation of distribution of one or more markers. Shifts were complex and could not be explained by change in maturation stage. In the majority of cases MRD populations more closely resembled the diagnostic than the relapse specimen. In 6 of 7 MRD negative cases we did not identify an abnormal population that resembled diagnosis or relapse. In the remaining case, in which CD34 and CD10 were lost between diagnosis and relapse, it is possible that we could have missed an MRD population resembling relapse., Conclusions: Phenotypic shifts are common, but do not affect MRD recognition. At most 1 of 42 cases might have harbored an abnormal population undetected because of shift. However, MRD analysis with rigid gating (looking strictly for abnormal phenotypes at diagnosis) might have missed many positive cases, 8 of 22 (36%) in this series., ((c) 2005 Wiley-Liss, Inc.)

Background: A robotically guided linear accelerator has recently been developed which provides frameless radiosurgery with high precision. Potential advantages for the pediatric population include the avoidance of the cognitive decline associated with whole brain radiotherapy, the ability to treat young children with thin skulls unsuitable for frame-based methods, and the possible avoidance of general anesthesia. We report our experience with this system (the "Cyberknife") in the treatment of 21 children., Procedures: Cyberknife radiosurgery was performed on 38 occasions for 21 patients, age ranging from 8 months to 16 years (7.0 +/- 5.1 years), with tumors considered unresectable. Three had pilocytic astrocytomas, two had anaplastic astrocytomas, three had ependymomas (two anaplastic), four had medulloblastomas, three had atypical teratoid/rhabdoid tumors, three had craniopharyngiomas, and three had other pathologies. The mean target volume was 10.7 +/- 20 cm(3), mean marginal dose was 18.8 +/- 8.1 Gy, and mean follow-up is 18 +/- 11 months. Twenty-seven (71%) of the treatments were single-shot and eight (38%) patients did not require general anesthesia., Results: Local control was achieved in the patients with pilocytic and anaplastic astrocytoma, three of the patients with medulloblastoma, and the three with craniopharyngioma, but not for those with ependymoma. Two of the patients with rhabdoid tumors are alive 16 and 35 months after this diagnosis. There have been no procedure related deaths or complications., Conclusion: Cyberknife radiosurgery can be used to achieve local control for some children with CNS tumors without the need for rigid head fixation., ((c) 2004 Wiley-Liss, Inc.)

Background and Purpose: Acute lymphocytic leukemia (ALL) is a common malignancy of childhood treated with methotrexate (MTX), which is associated with acute neurotoxicity. We evaluated diffusion-weighted (DW) and conventional MR images in children with ALL and acute MTX-induced neurotoxicity, with clinical correlation., Methods: Five patients aged 12-15 years underwent fluid-attenuated inversion recovery (FLAIR), T2-weighted fast spin-echo and gradient-echo, T1-weighted gadolinium-enhanced spin-echo, and DW imaging within 24 hours of symptom onset. Records were reviewed for the temporal relationship to MTX administration, strokelike symptoms, and neurologic outcome., Results: Six strokelike events were temporally related to intrathecal MTX given 6-11 days before symptom onset. FLAIR images showed abnormal hyperintensity in the callosal splenium in one patient but were otherwise normal. Diffusion abnormalities were frontoparietal in three events and frontal in one; nonfluent aphasia was seen in all. Bilateral frontoparietal diffusion abnormalities were associated with bilateral upper-extremity weakness, right-sided hemiparesis, or left-sided hemiparesis (one patient each); one patient had mild facial droop. Unilateral precentral subcortical diffusion abnormality was associated with contralateral motor deficit and ipsilateral upper-extremity sensory loss. Strokelike symptoms resolved rapidly and were not associated with other signs of encephalopathy. Subsequent intrathecal MTX administration was not associated with recurrence in four patients., Conclusion: Diffusion abnormalities in acute MTX neurotoxicity indicated cerebral dysfunction but not necessarily overt structural injury to the cerebrum. Subsequent demyelination or gliosis could not be predicted on the basis of diffusion abnormalities. A single strokelike episode with diffusion abnormalities should not necessarily prompt modification of potentially curative chemotherapeutic regimens.

Purpose: To determine the maximum tolerated dose and pharmacokinetics of Doxil in children with recurrent or refractory solid tumors. Doxil is pegylated doxorubicin., Experimental Design: Eligible patients were children with refractory tumors who had received cumulative anthracycline doses <300 mg/m(2). Cohorts of at least three patients each received escalating doses of Doxil starting at 40 mg/m(2) at 4-week intervals. If no dose-limiting toxicity occurred, dosages were escalated by increments of 10 mg/m(2) in subsequent cohorts. Originally, Doxil was administered over 60 min, but significant infusion reactions prompted longer infusion times of 4 h. Patients also received premedication with dexamethasone, ranitidine, and diphenhydramine 24 h before infusion, with ranitidine continued 24 h after infusion. Periodic blood samples were collected and plasma doxorubicin concentrations were quantified to characterize the pharmacokinetics of Doxil., Results: Between January 1997 and June 2000, 22 children ages 4-21 years with refractory tumors were treated with Doxil. Most patients had received one to five prior chemotherapy regimens, and all but five had prior radiotherapy (two had no prior therapy). Doxil was escalated to a dosage of 70 mg/m(2). At that level, dose-limiting mucositis was seen during the first cycle in two of six patients, thus defining dose-limiting toxicity, and in one additional patient during a subsequent cycle. Grade 4 neutropenia lasting less than 7 days was documented in two of six patients. The dose-limiting toxicity among two of six patients at 70 mg/m(2) was grade 3 mucositis during the first cycle of therapy. Painful desquamating dermatitis of the hands and feet, palmar-plantar erythrodysesthesia, occurred in six patients. In two of those patients, palmar-plantar erythrodysesthesia started as grade 1 and progressed to grade 2 during subsequent courses. Mean estimates of central volume of distribution, clearance, and elimination half-life were 1.45 liters/m(2), 0.03 liter/h/m(2), and 36.4 h, respectively., Conclusion: The maximum tolerated dose of Doxil administered every 4 weeks to pediatric patients was 60 mg/m(2). The effect of Doxil on pediatric patients with malignancies remains to be determined and should be studied in pediatric Phase II trials.

Background: The prognosis of children with high-grade astrocytomas of the central nervous system is grim and has not been substantially improved by conventional chemoradiotherapy. We performed a multi-institutional phase I study to determine the toxicities and tolerance of concurrent external beam radiation of the brain and a unique dose-schedule of paclitaxel as a radiation sensitizer., Procedure: Paclitaxel was delivered intravenously as a continuous 24 h/day, 7 days/week infusion during the entire 6-week course of fixed schedule standard radiation therapy. The dose of paclitaxel was escalated in patient cohorts in standard phase I design., Results: Eleven patients (eight brain stem gliomas, one glioblastoma multiforme, and two gliomatosis cerebri) were treated. Dose-limiting toxicity was encountered in the two patients treated at 6 mg/(m(2)/24 h), both of whom developed severe obstipation requiring prolonged hospitalization., Conclusions: We have shown in this first study of its kind that paclitaxel can be administered safely to children as a 6-week continuous infusion concurrent with cranial irradiation. The maximally tolerated and recommended phase II dose is 4 mg/(m(2)/day). The benefits of taxanes as clinical radiation sensitizers for children with high-grade gliomas, if any, remain to be determined., (Copyright 2001 Wiley-Liss, Inc.)

Purpose: Cyclophosphamide (CPA) has a broad spectrum of activity against solid tumors. Hepatic self-induction of the active metabolite 4-hydroxycyclophosphamide occurs after repeated administration. We evaluated the clinical efficacy of a window regimen that administers fractionated CPA in conjunction with etoposide (VP16) in children with advanced or refractory solid tumors., Patients and Methods: Seventeen children with advanced (n = 12) or refractory (n = 5) solid tumors were entered onto this phase II window study. The treatment regimen consisted of intravenous (IV) CPA 500 mg/m(2)/d and IV VP16 100 mg/m(2)/d. Both drugs were administered daily by short infusions for 5 consecutive days., Results: A total of 34 courses were administered, with a median of two courses per patient. The median interval between chemotherapy courses was 21 days (range, 17 to 35 days). Thirty-three courses were assessable for toxicity, and all patients were assessable for response. No life-threatening toxicities were observed. The incidence of grade 3 or 4 neutropenia was 94% and of fever and neutropenia 38%. Fever and neutropenia occurred after 12 of 26 courses without recombinant human granulocyte colony-stimulating factor (rhG-CSF) and after one of eight courses with rhG-CSF (P =. 09). Grade 3 or 4 thrombocytopenia occurred after 10 courses (29%). There were no positive blood cultures. One heavily pretreated patient developed a localized perirectal abscess that required drainage. There were 10 patients (59%) with partial responses, four (23.5%) with stable disease, and three with progressive disease., Conclusion: Fractionated IV CPA and VP16 over 5 days can be safely administered in children with advanced or refractory solid tumors and has notable antineoplastic activity.

To establish the maximum tolerated dosage (MTD), the dose-limiting toxicities (DLTs), and pharmacokinetic parameters of CI-980, a novel tubulin binder, in children with solid tumors refractory to standard therapy. Patients 21 years of age or younger with adequate nutritional, hematopoietic, renal, and hepatic function were eligible. The patient must not have been pregnant. Patients with brain tumors were not eligible for any dosage level until it was demonstrated the level did not produce DLT in patients with extracranial solid tumors. The starting dosage level was 3.5 mg/m2/day, for 3 days, administered as a continuous intravenous infusion (80% of the adult MTD). If a dosage level was associated with dose-limiting myelotoxicity, growth factors were to be added. Thirty-three patients received CI-980. Twenty-four had solid tumor; 9 had brain tumor. The MTD achieved without granulocyte colony stimulating factor (G-CSF) was 3.5 mg/m2/day (DLT: neutropenia) and with G-CSF, it was as follows: patients with brain tumor, 4.2 mg/m2/day (DLT: myelosupression); and patients with solid tumor, 5 mg/m2/day (DLT: cortical toxicity). Several responses were seen, most notably prolonged stable disease in two of five patients with medulloblastoma. Pharmacokinetic data showed a mean steady state level of 1.74 ng/mL for two patients treated with the 5 mg/m2/day regimen, with rapid decay after the termination of the infusion. CI-980 showed preliminary evidence of activity in recurrent pediatric malignancies, with tolerable, reversible toxicities.

Epipodophyllotoxins are associated with leukemias characterized by translocations of the MLL gene at chromosome band 11q23 and other translocations. Cytochrome P450 (CYP) 3A metabolizes epipodophyllotoxins and other chemotherapeutic agents. CYP3A metabolism generates epipodophyllotoxin catechol and quinone metabolites, which could damage DNA. There is a polymorphism in the 5' promoter region of the CYP3A4 gene (CYP3A4-V) that might alter the metabolism of anticancer drugs. We examined 99 de novo and 30 treatment-related leukemias with a conformation-sensitive gel electrophoresis assay for the presence of the CYP3A4-V. In all treatment-related cases, there was prior exposure to one or more anticancer drugs metabolized by CYP3A. Nineteen of 99 de novo (19%) and 1 of 30 treatment-related (3%) leukemias carried the CYP3A4-V (P = 0.026; Fisher's Exact Test, FET). Nine of 42 de novo leukemias with MLL gene translocations (21%), and 0 of 22 treatment-related leukemias with MLL gene translocations carried the CYP3A4-V (P = 0. 016, FET). This relationship remained significant when 19 treatment-related leukemias with MLL gene translocations that followed epipodophyllotoxin exposure were compared with the same 42 de novo cases (P = 0.026, FET). These data suggest that individuals with CYP3A4-W genotype may be at increased risk for treatment-related leukemia and that epipodophyllotoxin metabolism by CYP3A4 may contribute to the secondary cancer risk. The CYP3A4-W genotype may increase production of potentially DNA-damaging reactive intermediates. The variant may decrease production of the epipodophyllotoxin catechol metabolite, which is the precursor of the potentially DNA-damaging quinone.

Purpose: To study longitudinally the extent and recovery of cellular and humoral immune alterations in children with cancer after completion of their therapy., Patients and Methods: Using standard immune assays, cellular and humoral immunity was measured in 43 infants and children with cancer at completion of therapy and every 3 months thereafter for 1 year. There were 17 patients with acute lymphoblastic leukemia, 9 with Hodgkin disease, and 17 with solid nonhematopoietic tumors. All children had received standard childhood immunizations before diagnosis of cancer. Immune assays performed included circulating lymphocyte subpopulations, in vitro antigen-induced responses, and total concentrations of serum immunoglobulin G (IgG), IgM, IgA, and IgG subclasses, and specific antibodies against diphtheria, tetanus, pertussis, and poliovirus types I, II, and III., Results: At completion of therapy, the majority of patients had low circulating lymphocyte subpopulations and antigen-induced responses. Serum antibody concentrations were low in up to 89% of patients regardless of the underlying malignancy. Although improvement occurred during the year of follow-up, 35 of 43 (81%) patients continued to exhibit one or more immune abnormalities 9 to 12 months after cessation of chemotherapy. Younger patients had more persistent alterations. Other risk factors studied (including gender, duration of therapy, and underlying malignancy) did not correlate with the severity of the immune defects. With the exception of poliovirus antibodies, specific antibody titers against common childhood vaccine antigens were deficient at completion of therapy and 9 to 12 months later in a substantial proportion of patients., Conclusion: Children with malignancy have persistent specific and nonspecific immune alterations 9 to 12 months after cessation of chemotherapy. The clinical implications of these in vitro observations are unclear and require further evaluation.

Translocations of the MLL gene at chromosome band 11q23 are the most common cytogenetic alterations in de novo leukemia in infants and in leukemia related to chemotherapy with DNA topoisomerase II inhibitors. Experiments on knock-in mice suggest that additional mutational events may by required for full leukemogenesis. Therefore, we used single-strand conformation polymorphism analysis and an allele-specific restriction enzyme assay to investigate the frequency of KRAS and NRAS mutations in 32 pediatric leukemias with translocation of the MLL gene. Of 25 de novo cases, 13 were acute lymphoblastic leukemia (ALL), 10 were acute myeloid leukemia (AML), and 2 were biphenotypic. Three secondary leukemias were AML, 1 was biphenotypic, 1 was ALL, and 2 were diagnosed as myelodysplasia. The frequency of RAS mutations was 2 of 10 in de novo AML. Both mutations occurred in infant monoblastic variants. RAS mutations were otherwise absent in this series. This is the first report of congenital leukemias where translocation of the MLL gene and RAS mutation coexist. The frequency of RAS mutations in de novo AMLs with MLL gene translocations is similar to that in other forms of AML, but RAS mutations play a limited role in lymphoid and treatment-related leukemias with similar translocations.

Study Objective: To explore the value of high-dose methotrexate (MTX)., Subjects: Blast cells from 15 patients with acute lymphoblastic leukemia., Interventions: We compared uptake and polyglutamation of [3H]-MTX by freshly isolated leukemic blasts in vitro after 24-hour exposure to 1, 10, and 50 microM [3H]-MTX., Measurements and Main Results: Mean MTX uptake (pmol/10(6) cells) was 0.78 +/- 0.19, 2.3 +/- 0.54, and 5.9 +/- 1.9, respectively, and mean polyglutamation was 82%, 66%, and 46%. Consequently, mean MTX polyglutamates were 0.68 +/- 0.18, 1.5 +/- 0.47, and 2.2 +/- 0.67 pmol/10(6) cells. Three of 15 patient samples had no detectable polyglutamation of MTX at 50 microM but MTX polyglutamates were detectable at 1 microM. Two of these three had a decrease in MTX polyglutamates at 10 versus 1 microM. In eight precursor B cell samples there was a significant difference in median MTX polyglutamates at 1 versus 10 microM but not 10 versus 50 microM., Conclusion: Increasing extracellular MTX concentrations may be counterproductive for some patients with acute lymphoblastic leukemia. If MTX polyglutamates are important for efficacy, optimal delivery of MTX may have to be determined by individual metabolism rather than by targeting a specific drug concentration.

Purpose: This study reviewed the Pediatric Oncology Group experience with phase II clinical trials in children (< 21 years of age) with refractory tumors., Patients and Methods: Patients registered in Pediatric Oncology Group phase II studies were evaluated. Patients had to be < 21 years of age with recurrent and refractory measurable disease. Tumor types and response rates were determined. Death on therapy from either drug toxicity, progressive disease, infection, or hemorrhage was measured. Tumor-specific, disease-free survival curves were calculated by Kaplan-Meier analysis., Results: Between 1984 and 1994, 2,465 patient entries were made on 45 phase II trials. Malignancies registered included acute lymphocytic leukemia (ALL) (16.7%), acute myeloid leukemia (AML) (12.0%), osteogenic sarcoma (7.8%), neuroblastoma (7.2%), astrocytoma (7.2%), medulloblastoma (7.1%), glioma (6.7%), ependymoma (6.1%), and others (29.2%). The overall response rate was 19.6% (CR + PR) for children entered on phase II trials. Tumor-specific response rates ranged from 62.1% (23/37) for children with Hodgkin's disease to no responses (0/23) in patients with hepatoblastoma. When comparing single versus multiagent trials, a significantly better initial response rate was seen in the latter studies. However, 5-year survival was comparable. Progression-free survival for all tumor histologies were 12.9% and 9.2% at 2 and 5 years, respectively. Death on study was seen in 11.6% of the patients; however, only three deaths were directly related to drug toxicity. There were no significant gender differences in regards to response, progressive disease, or death on study., Conclusion: Phase II studies conducted in children offer a considerable likelihood of therapeutic benefit without exposing these patients to untoward toxicity.

Purpose: The purpose of this study is to report a case of Epstein-Barr virus-related lymphoproliferative disorder (EBV-related LPD) in a child with leukemia and present a review of literature on the subject., Patients and Methods: A 6-year-old boy with acute lymphoblastic leukemia (ALL) undergoing maintenance chemotherapy presented with fever, abdominal pain, and vomiting. Imaging studies revealed multiple mass lesions in the liver, kidneys, and lungs. Liver biopsy was obtained. Immunocytochemistry for T and B lymphocytes and in situ hybridization for evidence of latent EBV infection was performed., Results: Hepatic portal tracts were infiltrated with lymphocytes, monocytes, eosinophils, and large atypical mononuclear cells. Both T and B lymphocytes were present, but the large atypical cells were of B origin and were positive for latent EBV infection. Chemotherapy was discontinued, and the patient was treated with intravenous gammaglobulin, interferon, and acyclovir. He had an excellent response and has been free of disease for 19 months., Conclusion: EBV-related LPD can complicate the course of patients with ALL in remission. The clinical findings and diagnosis in patients with ALL are similar to other immunocompromised patients. Withdrawal of chemotherapy and treatment with immune modulators should be strongly considered.

Purpose: A phase I trial was conducted in children with refractory solid tumors to determine the maximum tolerated dose (MTD), dose-limiting toxicity (DLT), pharmacokinetics, and pharmacodynamics for topotecan administered by a 30-min infusion for 5 consecutive days., Patients and Methods: Forty children with a variety of recurrent solid tumors, including nine patients with neuroblastoma and 10 with brain tumors, were given topotecan as a 30-min infusion for 5 consecutive days, beginning with a dose of 1.4 mg/m2/day. The dose was escalated in 20% increments after establishing that DLT was not present at the prior dose. Drug toxicity was graded using standard criteria. Dose-limiting toxicity was defined as grade 3 or 4 nonhematopoietic toxicity or grade 4 hematopoietic toxicity lasting > 7 days. Pharmacokinetic studies were performed during the first infusion course., Results: The DLT was hematopoietic and involved both platelets and neutrophils. Grade 4 hematopoietic toxicity of brief duration was seen at all dose levels. Over half of the patients received red blood cell transfusion support, and 19/40 received platelet transfusions. Hospital admissions for fever and neutropenia or for documented infections occurred in 32 of 169 courses of therapy. Gastrointestinal symptoms with nausea and vomiting or diarrhea were mild to moderate in 12 of the 40 patients. Antitumor responses were seen in three patients with neuroblastoma. An additional four patients (one with neuroblastoma, two with anaplastic astrocytomas, one with Ewing) had stable disease with continued therapy for > 6 months. Using a limited sampling model, pharmacokinetic studies were performed in 36 of the 40 patients. Topotecan lactone and total clearance were similar to those reported in other pediatric populations receiving topotecan by continuous infusion. A pharmacodynamic relation between systemic exposure to topotecan lactone and myclosuppression was observed., Conclusions: In heavily pretreated children, the MTD for topotecan given by intermittent 30-min infusion for 5 days is 1.4 mg/m2 without GCSF and 2.0 mg/m2/day with GCSF. The dose-limiting toxicity is hematopoietic. Data from this study provide the basis for further studies of topotecan in children with cancer.

We investigated the frequency of p53 mutations in 19 pediatric cases of therapy-related leukemia or myelodysplastic syndrome. Eleven children presented with acute myeloid leukemia, one with mixed-lineage leukemia, two with acute lymphoblastic leukemia, and five with myelodysplasia at times ranging from 11 months to 9 years after a primary cancer diagnosis. The primary cancers, which included 11 solid tumors and eight leukemias, were treated with various combinations of DNA topoisomerase II inhibitors, alkylating agents, or irradiation. Leukemic or myelodysplastic marrows were screened for possible mutations by single-strand conformation polymorphism (SSCP) analysis of p53 exons 4 to 8. The only observed mutation was an inherited 2-basepair deletion at codon 209 in exon 6 that would shift the open reading frame, create a premature termination codon, and foreshorten the resultant protein. Prior therapy in this patient included DNA topoisomerase II inhibitors, alkylating agents, and irradiation. The secondary leukemia presented as myelodysplasia with monosomies of chromosomes 5 and 7 and abnormalities of chromosome 17. Although the primary cancer was an embryonal rhabdomyosarcoma and there was a family history of cancer, the case did not fulfill the clinical criteria for Li-Fraumeni syndrome. This study suggests that germline p53 mutations may predispose some children to therapy-related leukemia and myelodysplasia, but that p53 mutations otherwise are infrequent in this setting.

Seven years after completion of chemotherapy for acute lymphoblastic leukemia, diagnosed at the age of 5 years, a black female presented with signs of increased intracranial pressure. Neuroimaging showed a large enhancing extra-axial occipital tumor mass. The resection specimen showed morphologic, cytogenetic, and immunophenotypic features consistent with relapse of the primary leukemia. Bone marrow examination was negative for malignancy. The long duration of complete remission followed by the formation of a mass in the central nervous system are highly unusual features of recurrent acute lymphoblastic leukemia.

Clinical and laboratory investigations during the past four decades have resulted in numerous schedules, doses, and routes of delivery for methotrexate (MTX). It remains as an important drug for the treatment of children with acute lymphoblastic leukemia (ALL). Aminopterin (AMT) was the initial antifolate showing promise as an anticancer drug. It is more potent than MTX and also is known to be accumulated more efficiently than MTX in model systems. Because Whitehead et al. (Blood, 76: 44-49, 1990) have shown that MTX accumulation by blasts at diagnosis is of prognostic significance in children with ALL, we reasoned that if accumulation of a "stoichiometric inhibitor" of dihydrofolate reductase by leukemic blasts was of prognostic importance, then whether it was AMT or MTX may be relevant only with respect to the absolute dose. To compare MTX and AMT metabolism, we incubated lymphoblasts with 1 microM radiolabeled drug in vitro. MTX and AMT accumulation by ALL cells (n = 24) was 0.7 +/- 0.7 and 1.47 +/- 0.9 pmol/10(6) cells, respectively. Based on the data of Whitehead et al., this predicts pharmacological success in 59 and 84% of the MTX and AMT groups, respectively. Moreover, 5 of 10 patients considered poor risks based on MTX accumulation would be "cures" based on AMT uptake. Even at only 0.1 microM AMT, a concentration at which there is little accumulation of MTX, 5 of 11 patients studied would be "pharmacological cures" based on AMT uptake. Accumulation of AMT by blasts from 11 patients with T-cell-lineage ALL and 5 patients with acute myelogenous leukemia was also found to be twice the uptake of MTX. These data allow the suggestion that AMT, despite increased potential for toxicity, may be useful in children who are identified as poor risks with respect to MTX uptake.

We examined clinical, morphologic, and cytogenetic features and ALL-1 (MLL, Htrxl, HRX) gene rearrangements in 17 cases of secondary leukemia that occurred 11 months to 9 years from diagnoses of primary cancers in children who received topoisomerase II inhibitors or developed secondary leukemias typical of those associated with this therapy. Primary diagnoses included nine solid tumors and eight leukemias. Ten secondary leukemias were acute myeloid leukemia (AML), one was of mixed lineage, two were acute lymphoblastic leukemia (ALL), and four presented as myelodysplasia. Of 15 cases with 11q23 involvement, 11 (73%) were cytogenetically identifiable; four cases had molecular rearrangement only. By Southern blot, rearrangements within the ALL-1 gene were similar to sporadic cases. The results of this analysis suggest the following: (1) In most pediatric cases of topoisomerase II inhibitor-associated leukemia, there is disruption of the breakpoint cluster region of the ALL-1 gene at chromosomal band 11q23. (2) Exposure histories vary in secondary 11q23 leukemia, as the only topoisomerase II inhibitor was dactinomycin in one case, and, in another case, no topoisomerase II inhibitor was administered. (3) There is clinical, morphologic, cytogenetic, and molecular heterogeneity in pediatric secondary 11q23 leukemia. (4) There are some survivors of pediatric secondary 11q23 leukemia, but the outcome is most often fatal.

Prior to the development of intensive treatments for patients with advanced stage B-cell non-Hodgkin's lymphoma (B-NHL), the prognosis for such patients was dismal. A minority of patients attained long-term, disease-free survival. Since 1981, we have treated 28 children with advanced stage B-NHL with an intensive chemotherapeutic protocol, Total Therapy B. This regimen employs cycles of fractionated high-dose cyclophosphamide, doxorubicin, and vincristine alternating with sequential infusions of high-dose methotrexate and escalating doses of cytarabine, in addition to intensive intrathecal therapy. The planned duration of therapy is approximately 6 months. Two patients had B-cell acute lymphoblastic leukemia and 26 had stage III B-NHL; none had CNS involvement. The median age was 7 years. All 28 patients achieved complete remission (CR). Both patients with B-ALL and 21 of 26 with stage III B-NHL remain in CR, with a median follow-up of 51 months. Treatment failures included 3 patients with recurrent or progressive disease, 1 toxic death in CR, and 1 patient who developed a secondary mediastinal T-cell lymphoblastic lymphoma 4 1/2 years after the diagnosis of B-NHL. The 2- and 5-year event-free survival rates were 85.7 +/- 6.6% (SE) and 79.6 +/- 8.5%, respectively. Total Therapy B is a highly effective therapy for children with advanced stage B-NHL without CNS involvement.

Adenoviruses are gradually being recognized as a significant source of morbidity and mortality in the immunocompromised patient population. We report a bone marrow transplant patient who developed severe abdominal pain accompanied by marked elevations in serum pancreatic and hepatic enzyme levels. She died shortly thereafter. Autopsy revealed hemorrhagic pancreatitis and fulminant hepatic necrosis. Both the pancreas and liver contained intranuclear inclusions consistent with adenovirus; electron microscopy confirmed that there were, indeed, adenoviral particles. This report of adenoviral pancreatitis emphasizes the diversity of manifestations seen with adenoviral infection.

Translocations at chromosomal band 11q23 characterize most de novo acute lymphoblastic leukemias (ALL) of infants, acute myeloid leukemias (AML) of infants and young children, and secondary AMLs following epipodophyllotoxin exposure. The chromosomal breakpoints at 11q23 have been cloned from isolated cases of de novo ALL and AML. Using an 859-base pair BamHI fragment of human ALL-1 complementary DNA that recognizes the genomic breakpoint region for de novo ALL and AML, we investigated two cases of secondary AML that followed etoposide-treated primary B-lineage ALL. In the first case, the translocation occurred between chromosomes 9 and 11 and the breakpoint at 11q23 localized to the same 9-kilobase region of the ALL-1 gene that is disrupted in most of the de novo leukemias. In the second case the translocation was between chromosomes 11 and 19. The breakpoint occurred outside of the ALL-1 breakpoint cluster region.

The p53 gene was examined in primary or metastatic tumors from six patients with rhabdomyosarcoma (RMS) and in five RMS cell lines by screening methods including single-strand conformation polymorphism analysis, the RNase protection assay, sequencing of complementary DNA subclones, and Southern blotting. Six original tumors were of embryonal histology, four alveolar, and one mixed. p53 mutations were identified in four of the six tumors or cell lines derived from tumors with embryonal histology and in one of the four with alveolar histology. Consistent with p53 allele loss, each mutation was found in the homo- or hemizygous state. One tumor showed a G to C transversion at p53 codon 213 (arginine to proline), and another showed deletion of the entire gene. The p53 mutations in cell lines included a codon 248 C to T transition (arginine to tryptophan) in RD and a codon 280 A to T transversion (arginine to serine) in RH30. The cell line CTR contained a 4-base pair deletion at codons 219/220 in exon 6 with resultant frame shift and premature termination in exon 7. These data support the role of diverse types of p53 mutations in the pathogenesis and/or progression of a significant proportion of cases of childhood RMS.

Background: Our current protocol for treatment of childhood acute lymphoblastic leukemia (ALL) was designed to assess the efficacy of methotrexate (MTX) plus L-asparaginase and of etopisode (VP-16) plus cytarabine (ARA-C) during intensive consolidation and continuation therapies and to determine the feasibility of intensifying MTX therapy by the use of divided oral doses of MTX. The protocol was associated with unexpected acute neurotoxicity. There are few reports of such toxic effects during therapy for ALL., Purpose: This report describes these toxic effects and outlines our successful approach to the problem., Methods: The standard four-drug induction regimen consisted of vincristine, L-asparaginase, daunorubicin, and prednisone. In consolidation therapy, oral MTX was given in divided doses (dMTX) of 25 mg/m2 every 6 hours four times daily in four weekly courses concomitant with weekly triple intrathecal therapy--MTX, ARA-C, and hydrocortisone--plus one dose of leucovorin 24 hours after triple intrathecal therapy. Consolidation treatment ended with three daily doses of intravenous VP-16 and ARA-C. The first 16 months of continuation therapy included 6-week cycles of dMTX and L-asparaginase, both given every other week for 5 weeks, with 6-mercaptopurine nightly, and then two doses of VP-16 plus ARA-C and one dose of triple intrathecal therapy., Results: Twenty-five of the 138 patients evaluated had acute neurotoxicity. Ten of the first 72 experienced a seizure or episode of transient neurological deficit 9-11 days following the administration of intravenous ARA-C, VP-16, and triple intrathecal therapy. Despite discontinuation of intrathecal ARA-C, which eliminated simultaneous intravenous and intrathecal treatment with ARA-C, acute neurotoxicity was observed in six previously unaffected patients and six of 42 patients treated after the elimination of intrathecal ARA-C. Therefore, as a second amendment, oral leucovorin was given 24 and 36 hours after dMTX and intrathecal MTX in continuation therapy. No acute neurotoxicity has been seen in 24 patients subsequently entered in the study., Conclusion: These findings suggest that folate replacement due to administration of leucovorin modulated MTX toxicity and/or modified an interaction among VP-16, ARA-C, intrathecal therapy, and the central nervous system.

2-Deoxycoformycin (DCF) was added to an intensive Pediatric Oncology Group protocol (#8303) for children with T-cell acute lymphoblastic leukemia or T-cell lymphoblastic lymphoma in first relapse. Twenty-seven patients received one or more courses of DCF at 15 mg/m2/day as a 3-day continuous infusion immediately after achieving a second remission with a four-drug reinduction regimen. Renal and neuromuscular toxicities were frequent and occasionally severe despite the provision of a source of adenosine deaminase by means of a packed red cell transfusion 1 day following the infusion of DCF. Hepatic toxicity, manifested by transaminase elevations, accompanied 62% of the courses. The median duration of the second complete remission was 4 months (range 2-16+ months), with only two of the 27 patients still in remission at 13+ and 16+ months. Plasma concentrations of deoxyadenosine (dAdo) and the ratio of red cell deoxyadenosine triphosphate to adenosine triphosphate (dATP:ATP) were measured prior to the DCF infusion and on day 4. A dATP:ATP ratio of 1.0 or greater was seen in two patients with acute renal failure. There was no apparent correlation between toxicity or response and the plasma dAdo concentrations. DCF administered according to this dose and schedule was excessively toxic and did not appreciably prolong the duration of the second complete remission in children with T-cell lymphoblastic malignancies.

We conducted a phase I and pharmacokinetic study of i.v. idarubicin, a new anthracycline analogue, in 42 evaluable children 1-19 years old. Twenty-seven had leukemia and 15 had various solid tumors. The drug was administered in escalating doses of 10 to 40 mg/m2/course in 3 equal fractions over 3 consecutive days at 14- to 21-day intervals. Myelosuppression and mucositis were the limiting toxicities for short-term administration. Nausea, vomiting, and elevation of liver enzymes and bilirubin were the other toxicities encountered. Peak toxicity occurred 2 weeks after drug administration with median recovery by day 24. All but 4 patients with solid tumors had prior anthracyclines. Mild cardiac function changes without clinical symptoms were observed in 17 of 35 patients measured by serial cardiac evaluations. In addition, there were 4 patients with congestive heart failure. On postmortem examination, 4 patients had changes consistent with anthracycline cardiomyopathy at a prior median total anthracycline dose of 175 mg/m2. The maximum tolerated dose for patients with solid tumors was 15 mg/m2 course in 3 divided doses. Patients with leukemia tolerated 30 mg/m2/course. Six of 15 evaluable patients with acute lymphoblastic leukemia who received greater than or equal to 30 mg/m2 idarubicin achieved a remission (M1 marrow status). The plasma clearance of idarubicin fits a 3-compartment model with a harmonic mean half-life of 2.4 min, 0.6 h, and 11.3 h for alpha, beta, and gamma phases, respectively. Idarubicinol was the only metabolite detected in the plasma and it accumulated during the 3 days of therapy. Idarubicin is similar to daunorubicin in pharmacology and toxicity. While the cardiotoxic dose still must be delineated, the complete remission achieved in multiple relapsed patients with acute lymphoblastic leukemia indicate promising activity in at least that disease.

Iproplatin was evaluated in a phase I study in children to determine the maximum tolerated dosage. The dose-limiting toxic effect was found to be myelosuppression, which in part was related to the amount of prior therapy with irradiation and other anticancer agents. The dosage recommended for phase II trials in children is 324 mg/m2 iv over 2 hours every 3-4 weeks.

Methotrexate (MTX), a mainstay in the treatment of acute lymphoblastic leukemia, is associated with both hepatic and neurologic toxicity. Like a folate, MTX is metabolized to polyglutamated derivatives (MTXGlun) with long intracellular half-lives. These metabolites may contribute to MTX toxicity through a direct effect on cellular metabolism or indirectly through a perturbation of folate homeostasis. To better define the effects of chronic MTX treatment, tissue levels of MTX, MTXGlun, and folate were measured in three monkeys treated with weekly intramuscular MTX for 1 year. Greater than 80% of the total tissue MTX found was in the form of polyglutamated derivatives. Most of these derivatives were MTXGlu3-5 but Glu6-7 were easily detectable. Total tissue folates were measured in liver, kidney, brain and testis with MTX treated animals having a 90% loss of total folate in brain tissue. This is of special interest since inborn errors of folate metabolism are often associated with severe neurologic abnormalities.