Pediatric palliative care.

This article presents a model of integrated palliative care for children with life-limiting illnesses, with emphasis on collaboration of care over time among family, primary care providers, and several other groups of providers. Some of the unique aspects of caring for children related to normal developmental changes and the family unit are considered. Issues related to pain and to specific diseases are also reviewed.

Hb Dartmouth [alpha66(E15)Leu-->Pro (alpha2) (CTG-->CCG)]: a novel alpha2-globin gene mutation associated with severe neonatal anemia when inherited in trans with Southeast Asian alpha-thalassemia-1.

We report a novel mutation at alpha66(E15)Leu-->Pro (alpha2) (CTG-->CCG), that we have named Hb Dartmouth for the medical center at which the patients were cared for, in monozygotic twins who also inherited the Southeast Asian alpha-thalassemia-1 deletion. The mother, of Khmer ancestry, is heterozygous for alpha-thalassemia-1. The father, who is of Scottish-Irish ancestry, is a silent carrier of the codon 66 mutation. The twins had severe neonatal anemia requiring transfusion.

Toxicity, pharmacology and feasibility of administration of PEG-L-asparaginase as consolidation therapy in patients undergoing bone marrow transplantation for acute lymphoblastic leukemia.

We attempted to administer PEG-L-asparaginase (PEG-L-A) following hematologic recovery to 38 patients undergoing autologous or allogeneic marrow transplantation for acute lymphoblastic leukemia (ALL). Twenty-four patients (12 of 22 receiving allogeneic and 12 of 16 receiving autologous transplants) received between one and 12 doses of PEG-L-A, including nine who completed the planned 12 doses of therapy. The toxicities encountered were similar to those observed in non-transplanted patients undergoing therapy with PEG-L-A and included allergic reactions, pancreatitis, weight loss, hypoalbuminemia, and low levels of anti-thrombin III. Of the 24 who received the drug, eight remain in remission. Of 12 patients in second remission at the time of transplantation who received PEG-L-A, five of seven who received allogeneic and two of five who received autologous transplants remain in remission, 16+ to 46+ months from transplant. While PEG-L-A could be administered to most of the patients undergoing marrow transplantation for ALL, most patients either relapsed while receiving the drug or developed toxicities which resulted in abbreviated courses. At this time, we cannot recommend PEG-L-A as single agent, post-BMT chemotherapy.

Health campaign channels: tradeoffs among reach, specificity, and impact.

PIP: Stanford University's Five-City Multifactor Risk Reduction Project (FCP) was a 14-year trial of community-wide cardiovascular disease (CVD) risk reduction through integrated programs of community organization and mass media health promotion. The project was launched in 1978 in 5 central California cities, including Monterey, Salinas, Modesto, and San Luis Obispo. TV public service announcements (PSAs), TV shows, booklets, printed tip sheets with brief health suggestions on 7 topics, and newspaper coverage were the types of mass media approaches used in the FCP. These strategies are compared with regard to reach, specificity, and impact for a 5-year study period from 1979/80. Reach is measured as the number of messages intervention community residents remembered, specificity was assessed by examining whether the campaign differentially reached people who were already knowledgeable and practicing cardiovascular disease risk reduction, and impact is defined as the amount of knowledge gained during the course of the campaign. Reach was highest for tip sheets, while specificity was highest for booklets followed by TV programs. Newspaper messages had the most impact, followed by booklets and TV PSAs, tip sheets, and TV programs. Communication channels varied according to reach, specificity, and impact, with each criterion being distinct. No channel was optimal for all 3 of the outcome measures.^ieng

High-dose chemotherapy with autologous stem-cell rescue in patients with recurrent and high-risk pediatric brain tumors.

PURPOSE: We treated 49 patients with recurrent or poor-prognosis CNS malignancies with high-dose chemotherapy regimens followed by autologous marrow rescue with or without peripheral-blood stem-cell augmentation to determine the toxicity of and event-free survival after these regimens. PATIENTS AND METHODS: Nineteen patients had medulloblastomas, 12 had glial tumors, seven had pineoblastomas, five had ependymomas, three had primitive neuroectodermal tumors, two had germ cell tumors, and one had fibrosarcoma. Thirty-seven received chemotherapy with cyclophosphamide 1.5 g/m2 daily x 4 and melphalan 25 to 60 mg/m2 daily x 3. Nine received busulfan 37.5 mg/m2 every 6 hours x 16 and melphalan 180 mg/m2 (n = 7) or 140 mg/m2 (n = 2). Three received carboplatin 700 mg/m2/d on days -7, -5, and -3 and etoposide 500 mg/m2/d on days -6, -4, and -2. All patients received standard supportive care. RESULTS: Eighteen of 49 patients survive event-free 22+ to 55+ months (median, 33+) after transplantation, including nine of 16 treated before recurrence and nine of 33 treated after recurrence. There was one transplant-related death from pulmonary aspergillosis. Of five patients assessable for disease response, one had a partial remission (2 months), one has had stable disease (55+ months), and three showed progression 2, 5, and 8 months after transplantation. CONCLUSION: The toxicity of these regimens was tolerable. Certain patients with high-risk CNS malignancies may benefit from such a treatment approach. Subsequent trials should attempt to determine which patients are most likely to benefit from high-dose chemotherapy with autologous stem-cell rescue.

Constitutional de novo t(1;22)(p22;q11.2) and ependymoma.

There is a body of evidence suggesting the presence of a tumor suppressor gene on chromosome 22 which plays a role in the pathogenesis of ependymomas. We report a patient with a de novo constitutional t(1;22)(p22;q11.2) who developed a malignant ependymoma at age 5. The patient is otherwise phenotypically normal. By fluorescence in situ hybridization (FISH) analysis, the chromosome 22 breakpoint has been localized to the region between the DiGeorge locus and BCR. Since NF2 and EWS are both distal to BCR, the are presumable not involved in this rearrangement. This patient may offer a unique opportunity to identify the chromosome 22 ependymoma tumor suppressor gene by cloning the translocation breakpoint.

Health insurance access to young adult survivors of childhood cancer in North Carolina.

Historically, there has been evidence to support the hypothesis that survivors of childhood cancer have been discriminated against in the private health insurance market in some areas of the United States. Results of previous studies have been inconsistent and have generally focused on a limited number of outcome variables. A retrospective cohort study of young adult survivors of childhood cancer and their siblings was performed to determine the risk of health insurance access problems of childhood cancer survivors in North Carolina. Mailed questionnaires were completed by 182 cancer survivors from three institutions who were diagnosed between 1976 and 1988, and by 101 of their siblings for a response of 62.1%. Using logistic regression in SAS, cancer survivors were found to be more likely to be denied health insurance than their siblings, with an adjusted odds ratio of 15.1. Childhood cancer survivors also had health insurance policies that excluded care for pre-existing medical conditions more often than their siblings (OR = 5.5). In addition, cancer survivors reported problems obtaining health insurance coverage more frequently than their siblings with an adjusted odds ratio of 22.8. In general, survivors of childhood cancer who were diagnosed in North Carolina have had decreased access to health insurance coverage when compared to their siblings of similar age. North Carolina health insurance regulations permit health insurance firms to discriminate against cancer survivors because of their history of illness, often decreasing their access to needed follow-up care.

epsilon-Aminocaproic acid-associated myopathy in a child.

PURPOSE: A 12-year-old girl developed severe autoimmune thrombocytopenia after a bone marrow transplant for acute lymphoblastic leukemia. RESULTS: Although epsilon-aminocaproic acid helped to control her bleeding, it eventually caused a rare myopathy previously undescribed in a pediatric patient. CONCLUSION: The myopathy resolved when the drug was discontinued and a different antifibrinolytic agent was used.

A pilot study of isotretinoin in the treatment of juvenile chronic myelogenous leukemia.

BACKGROUND: Juvenile chronic myelogenous leukemia (CML) is a rare myeloproliferative disease of infants and young children for which there is no effective therapy other than allogeneic bone marrow transplantation. In vitro, isotretinoin (13-cis-retinoic acid) attenuates both the spontaneous proliferation of leukemic peripheral-blood progenitor cells (granulocyte-macrophage colony-forming units) and their selective hypersensitivity to granulocyte-macrophage colony-stimulating factor (GM-CSF). We conducted a pilot study to evaluate the clinical efficacy of isotretinoin in juvenile CML. METHODS: To be eligible the patients had to have newly diagnosed untreated disease, leukocytosis with monocytosis, marrow with less than 25 percent blasts, hepatosplenomegaly, no chromosomal abnormalities, and negative viral cultures and antibody titers. Isotretinoin was administered orally in single daily doses of 100 mg per square meter of body-surface area. When possible, patients subsequently underwent bone marrow transplantation. RESULTS: Ten children (median age, 10 months) were enrolled in the study. In all 10 there was spontaneous colony formation of leukemic progenitor cells in vitro. In the eight patients tested there was hypersensitivity to GM-CSF. The only toxic effect of isotretinoin therapy was cheilitis in two patients. Four children had disease progression. Two children had complete responses to isotretinoin (normalization of the white-cell count and disappearance of organomegaly), three had partial responses (more than a 50 percent reduction in the white-cell count and degree of organomegaly), and one had a minimal response (more than a 50 percent reduction in the white-cell count, but a 26 to 50 percent reduction in the degree of organomegaly). The median duration of response was 37 months (range, 6 to 83). Three of the four children who had a complete or partial response and who did not undergo bone marrow transplantation were alive 36 to 83 months after the diagnosis of juvenile CML. The spontaneous colony formation in vitro was reduced in samples from the five patients in whom this factor was reassessed during treatment. There was also a reduction in the hypersensitivity of leukemic progenitor cells to GM-CSF in the two patients retested. CONCLUSIONS: Isotretinoin can induce durable clinical and laboratory responses in patients with juvenile CML.

Efficacy and toxicity of 9-beta-D-arabinofuranosylguanine (araG) as an agent to purge malignant T cells from murine bone marrow: application to an in vivo T-leukemia model.

9-beta-D-Arabinofuranosylguanine (araG), an analog of deoxyguanosine which is not degraded by purine nucleoside phosphorylase, has been previously shown in in vitro studies by our laboratory to be effective in purging malignant T cells from human bone marrow (1). We now describe studies in a murine model of T-cell acute lymphoblastic leukemia (ALL) in which we tested whether bone marrow, contaminated with malignant T cells and purged ex vivo with araG, could reconstitute both the lymphoid and myeloerythroid lineages in the absence of leukemic relapse. The model utilized 6C3HED tumor cells, derived from a Thy 1.2+ malignant murine T-cell line, which were shown to cause lethal leukemia in C3H/HeN mice. Intravenous injection of 10(6) 6C3HED cells resulted in 100% mortality within 18 days, with autopsy revealing tumor infiltration of multiple organs. 100% of non-leukemia bearing lethally irradiated C3H/HeN mice transplanted with syngeneic bone marrow, treated ex vivo with 100 microM of araG for 18 hours, survived > 365 days post-transplant with full lymphohematopoietic reconstitution. Evidence of araG's ability to purge bone marrow of malignant tumor cells without causing significant toxicity to normal marrow derived hematopoietic progenitor cells was documented in experiments in which 75% of lethally irradiated mice transplanted with syngeneic bone marrow, contaminated with 6C3HED tumor cells and treated ex vivo with 100 microM araG for 18 hours, survived for > 250 to > 400 days. Death in 25% of mice was secondary to infection which developed before marrow reconstitution occurred. Reconstitution of the lymphoid, myeloid, and erythroid lineages with donor cells in surviving mice was documented. The data presented indicate that araG may effectively purge bone marrow of malignant T cells without irreversible toxicity to hematopoietic stem cells. This purging regimen is recommended for consideration for clinical trials in patients with T-cell malignancies undergoing autologous bone marrow transplantation and may also be a viable option for T-cell depletion as a strategy to prevent graft-versus-host disease.

Suppression of an antibody to adenosine-deaminase (ADA) in an ADA-deficient patient receiving polyethylene glycol modified adenosine deaminase.

An adenosine deaminase (ADA) deficient patient with severe combined immunodeficiency (SCID) developed resistance to therapeutic injections of bovine ADA conjugated to polyethylene glycol (PEG-ADA). This 18-year-old girl was diagnosed as having partial ADA deficiency at age 7 years, and was started on bovine conjugated PEG-ADA at age 15 years. The weekly dose of 15 U/kg led to clinical improvement with resolution of sinusitis and bronchitis within 2 months and normalization of some T cell functions. After 5 months, however, she developed an inhibitory antibody to ADA, became refractory to treatment with PEG-ADA, and clinically and immunologically deteriorated. This antibody was successfully suppressed over a 4-month period with a combination of prednisone (2 mg/kg/day), intravenous immunoglobulin (2 g/kg/dose), and discontinuing the PEG-ADA injections for 7 weeks. The PEG-ADA injections were then restarted at a higher dose (20 U/kg/dose, twice a week). With the suppression of the inhibitory antibody, her clinical and immunologic status improved to previously achieved level. She has subsequently continued treatment for over 36 months, receiving a single weekly dose of PEG-ADA (20 U/kg/week) with sustained clinical and immunologic improvement, including weakly positive antigen-specific T cell proliferative responses to tetanus and Candida.

Enzyme replacement therapy with polyethylene glycol-adenosine deaminase in adenosine deaminase deficiency: overview and case reports of three patients, including two now receiving gene therapy.

During the past 6 y, 29 adenosine deaminase (ADA)-deficient patients with combined immunodeficiency have been treated with polyethylene glycol (PEG)-modified bovine ADA (PEG-ADA). We have monitored plasma ADA activity, metabolic effects of treatment, and the evolution of antibody to PEG-ADA in these patients, in collaboration with immunologists and clinicians in North America, Europe, and Australia, who have monitored immune function and clinical response to treatment. This article summarizes the current status of PEG-ADA therapy and provides recommendations for its use. Recovery of specific immune function during treatment with PEG-ADA is illustrated for three patients, who represent early, delayed, these patients have entered a trial of gene therapy, but continue to receive enzyme replacement.

IgG antibody response to polyethylene glycol-modified adenosine deaminase in patients with adenosine deaminase deficiency.

Polyethylene glycol (PEG)-modified bovine adenosine deaminase (ADA) is used for replacement therapy of severe combined immunodeficiency disease due to inherited ADA deficiency. We monitored IgG anti-ADA antibody in 17 patients treated by intramuscular injections of PEG-ADA for 1 to greater than 5.5 yr. ELISA-detectable anti-ADA IgG appeared in 10 patients, usually between the third and eighth months of treatment. Anti-ADA levels did not correlate with trough plasma ADA activity, which averaged 1.8-5 times normal blood (erythrocyte) ADA activity, depending on dose (15-60 U/kg per wk). ELISA-detectable anti-ADA antibodies were directed primarily at bovine-specific peptide (rather than PEG-containing) epitopes. Enhanced enzyme clearance, mediated by antibody that directly inhibited native and PEG-modified bovine ADA, and native, but not PEG-modified human ADA, occurred in two patients. In one, tolerance was induced; in the second, twice weekly injections of PEG-ADA compensated for accelerated clearance. We speculate that inhibitory antibodies recognize conserved, relatively PEG-free epitope(s) encompassing the active site, and that in human, but not bovine, ADA a PEG-attachment site "shields" the active site from immune recognition. We conclude that PEG-modification largely prevents the development of high affinity, or high levels of clearing antibodies to bovine ADA, and that PEG-modified human ADA should be further investigated as a possible treatment for ADA deficiency.

Pharmacologic purging of malignant T cells from human bone marrow using 9-beta-D-arabinofuranosylguanine.

Arabinosylguanine (araG) is a nucleoside analog that is rapidly converted by cells of the T lymphoid lineage to its corresponding arabinosylguanine nucleotide triphosphate, resulting in inhibition of DNA synthesis and selective in vitro toxicity to T lymphoblastoid cell lines as well as to freshly isolated leukemia cells from patients with T cell acute lymphoblastic leukemia. In this report, we demonstrate that araG is an effective agent to use for chemoseparation of malignant T lymphoblasts from human bone marrow. When freshly isolated human T leukemia cells or T lymphoblastoid cells were treated with 100 microM araG for 18 hr, up to 6 logs of clonogenic T cells could be eliminated without appreciable toxicity to the normal myeloid, erythroid, and megakaryocytoid clonal progenitor cells. We discuss the use of this agent in ex vivo elimination of residual malignant T cells from marrow of patients requiring myeloablative chemotherapy with autologous bone marrow rescue.

Use of site-directed mutagenesis to enhance the epitope-shielding effect of covalent modification of proteins with polyethylene glycol.

Modification by covalent attachment of polyethylene glycol (PEG) can reduce the immunogenicity and prolong the circulating life of proteins, but the utility of this approach for any protein is restricted by the number and distribution of PEG attachment sites (e.g., epsilon-amino groups of lysine residues). We have developed a strategy for introducing additional sites for PEG attachment by using site-directed mutagenesis to selectively replace arginine with lysine codons and tested it with purine nucleoside phosphorylase (PNP) from Escherichia coli, an extremely stable but immunogenic enzyme, that could potentially be used to treat an inherited deficiency of PNP. A triple mutant, RK3, possessing three Arg----Lys substitutions was constructed that increased the number of lysines per PNP subunit from 14 to 17, providing an additional 18 potential PEG attachment sites per hexameric enzyme molecule. The wild-type and RK3 enzymes had similar catalytic activity, antigenicity, and immunogenicity. After PEG modification, both enzymes retained catalytic activity, the plasma half-life of both enzymes in mice increased from approximately 4 hr to 4 days, and the binding of both enzymes by antisera raised against each unmodified enzyme was markedly diminished. However, antibody raised against wild-type PEG-PNP did not bind the PEG-RK3 enzyme. PEG-RK3 PNP was also substantially less immunogenic than wild-type PEG-PNP. Accelerated antibody-mediated clearance of PEG-PNP occurred in 2 of 12 mice treated with PEG-RK3 PNP, compared with 10 of 16 mice treated with the modified wild-type enzyme. This combined use of directed mutagenesis and PEG modification is aimed at permitting the widest choice of proteins, including products of genetic and chemical "engineering," to be used for therapy of inherited and acquired disorders.

Paradoxical expression of adenosine deaminase in T cells cultured from a patient with adenosine deaminase deficiency and combine immunodeficiency.

T lymphocytes cultured from a patient (T.D.) with adenosine deaminase (ADA) deficiency expressed ADA activity in the normal range, inconsistent with her severe immunodeficiency, metabolic abnormalities, and with the absence of ADA activity in her B lymphocytes and other nucleated hematopoietic cells. ADA from T.D. T cells had normal Km, heat stability, and sensitivity to ADA inhibitors. Examination of HLA phenotype and polymorphic DNA loci indicated that T.D. was neither chimeric nor a genetic mosaic. Amplified and subcloned ADA cDNA from ADA+ T.D. T cells was shown by allele-specific oligonucleotide hybridization to possess the same mutations (Arg101----Trp, Arg211----His) previously found in the ADA-T.D. B cell line GM 2606 (Akeson, A. L., D. A. Wiginton, M. R. Dusing, J. C. States, and J. J. Hutton. 1988. J. Biol. Chem. 263:16291-16296). Our findings suggest that one of these mutant alleles can be expressed selectively in IL-2-dependent T cells as stable, active enzyme. Cultured T cells from other patients with the Arg211----His mutation did not express significant ADA activity, while some B cell lines from a patient with an Arg101----Gln mutation have been found to express normal ADA activity. We speculate that Arg101 may be at a site that determines degradation of ADA by a protease that is under negative control by IL-2 in T cells, and is variably expressed in B cells. Il-2 might increase ADA expression in T cells of patients who possess mutations of Arg101.