Busulfan with 400 centigray of total body irradiation and higher dose fludarabine: An alternative regimen for hematopoietic stem cell transplantation in pediatric acute lymphoblastic leukemia.

BACKGROUND: Hematopoietic stem cell transplantation can be curative for children with difficult-to-treat leukemia. The conditioning regimen utilized is known to influence outcomes. We report outcomes of the conditioning regimen used at the Alberta Children's Hospital, consisting of busulfan (with pharmacokinetic target of 3750 µmol*min/L/day ±10%) for 4 days, higher dose (250 mg/m2 ) fludarabine and 400 centigray (cGy) of total body irradiation. PROCEDURE: This retrospective study involved children receiving transplant for acute lymphoblastic leukemia (ALL). It compared children who fell within the target range for busulfan with those who were either not measured or were measured and fell outside this range. All other treatment factors were identical. RESULTS: Twenty-nine children (17 within target) were evaluated. All subjects engrafted neutrophils with a median [interquartile range] time of 14 days [8-30 days]. The cumulative incidence of acute graft-versus-host disease was 44.8% [95% confidence interval, CI: 35.6%-54.0%], while chronic graft-versus-host disease was noted in 16.0% [95% CI: 8.7%-23.3%]. At 2 years, the overall survival was 78.1% [95% CI: 70.8%-86.4%] and event-free survival was 74.7% [95% CI: 66.4%-83.0%]. Cumulative incidence of relapse was 11.3% [95% CI: 5.1%-17.5%]. There were no statistically significant differences in between the group that received targeted busulfan compared with the untargeted group. CONCLUSION: Our conditioning regiment for children with ALL resulted in outcomes comparable to standard treatment with acceptable toxicities and significant reduction in radiation dose. Targeting busulfan dose in this cohort did not result in improved outcomes.

LNK/SH2B3 as a novel driver in juvenile myelomonocytic leukemia.

Mutations in five canonical Ras pathway genes (NF1, NRAS, KRAS, PTPN11 and CBL) are detected in nearly 90% of patients with juvenile myelomonocytic leukemia (JMML), a frequently fatal malignant neoplasm of early childhood. In this report, we describe seven patients diagnosed with SH2B3-mutated JMML, including five patients who were found to have initiating, loss-of-function mutations in the gene. SH2B3 encodes the adaptor protein LNK, a negative regulator of normal hematopoiesis upstream of the Ras pathway. These mutations were identified to be germline, somatic or a combination of both. Loss of function of LNK, which has been observed in other myeloid malignancies, results in abnormal proliferation of hematopoietic cells due to cytokine hypersensitivity and activation of the JAK/STAT signaling pathway. In vitro studies of induced pluripotent stem cell-derived JMML-like hematopoietic progenitor cells also demonstrated sensitivity of SH2B3-mutated hematopoietic progenitor cells to JAK inhibition. Lastly, we describe two patients with JMML and SH2B3 mutations who were treated with the JAK1/2 inhibitor ruxolitinib. This report expands the spectrum of initiating mutations in JMML and raises the possibility of targeting the JAK/STAT pathway in patients with SH2B3 mutations.

Prediction of whole body composition utilizing cross-sectional abdominal imaging in pediatrics.

BACKGROUND: Although body composition is an important determinant of pediatric health outcomes, we lack tools to routinely assess it in clinical practice. We define models to predict whole-body skeletal muscle and fat composition, as measured by dual X-ray absorptiometry (DXA) or whole-body magnetic resonance imaging (MRI), in pediatric oncology and healthy pediatric cohorts, respectively. METHODS: Pediatric oncology patients (≥5 to ≤18 years) undergoing an abdominal CT were prospectively recruited for a concurrent study DXA scan. Cross-sectional areas of skeletal muscle and total adipose tissue at each lumbar vertebral level (L1-L5) were quantified and optimal linear regression models were defined. Whole body and cross-sectional MRI data from a previously recruited cohort of healthy children (≥5 to ≤18 years) was analyzed separately. RESULTS: Eighty pediatric oncology patients (57% male; age range 5.1-18.4 y) were included. Cross-sectional areas of skeletal muscle and total adipose tissue at lumbar vertebral levels (L1-L5) were correlated with whole-body lean soft tissue mass (LSTM) (R2 = 0.896-0.940) and fat mass (FM) (R2 = 0.874-0.936) (p < 0.001). Linear regression models were improved by the addition of height for prediction of LSTM (adjusted R2 = 0.946-0.971; p < 0.001) and by the addition of height and sex (adjusted R2 = 0.930-0.953) (p < 0.001)) for prediction of whole body FM. High correlation between lumbar cross-sectional tissue areas and whole-body volumes of skeletal muscle and fat, as measured by whole-body MRI, was confirmed in an independent cohort of 73 healthy children. CONCLUSION: Regression models can predict whole-body skeletal muscle and fat in pediatric patients utilizing cross-sectional abdominal images.

ADaPTS "(AD)olescents (P)ath through (T)ransplant (S)ickle cell disease".

BACKGROUND: Sickle cell disease is an inherited chronic hematological disorder with an average lifespan of fifty years. The human cost of sickle cell disease includes missed school days, occupational opportunities, social isolation, stigmatization, and psychological sequelae. Hematopoietic cell transplantation (HCT) is the only curative therapy available but comes with potential morbidity and mortality. Our study explores how quality of life (QoL) is affected from the perspective of an adolescent who has undergone a nonmyeloablative matched sibling donor HCT. METHODS: We employed multiple case study methodology with purposeful sampling by selecting information-rich cases. DATA SOURCES: 1) QoL inventories 2) patient interviews 3) parent interview 4) vital support interview 5) medical record analysis. DATA ANALYSIS: Intra-case analysis by assembling evidence within a single case and then analyzing the differences within cases to create a rich case description. Next, a time series analysis was completed to track changes in patients' QoL. We used multiple sources of data to compose a timeline and changes across time. Then, we employed pattern matching as an analytical technique allowing for examination of patterns across cases. Finally, we used cross case synthesis to review results of each case. RESULTS: Quality of life was reported across the physical, social and psychological domains for 5 participants. All had sickle cell HgSS genotype, 80% were male and 80% were born outside of Canada. Physical domain: pre-transplant, 100% of patients experienced pain, and the majority suffered from fatigue, insomnia, and fevers resulting in hospitalizations. Afterwards, participants reported improved physical wellbeing. Social domain: pre-transplant, QoL was poor characterized by stigma, social isolation, and parental absenteeism. Post-HSCT adolescents gained social acceptance in areas that had stigmatized and excluded them. They were able to participate freely in activities with peers and their social life vastly improved. Psychological pre-transplant life experiences were overshadowed by psychological stress. The majority commented that their future was bleak and may lead to premature death. Afterwards adolescents described a crisis free life with positive psychological outcomes. CONCLUSIONS: Adolescents with sickle cell disease who undertook HCT demonstrated improved QoL one year post transplant with regard to physical, social and psychological well-being.

Mechanistic understanding of the combined immunodeficiency in complete human CARD11 deficiency.

BACKGROUND: Germline pathogenic variants impairing the caspase recruitment domain family member 11 (CARD11)-B cell chronic lymphocytic leukemia/lymphoma 10 (BCL10)-MALT1 paracaspase (MALT1) (CBM) complex are associated with diverse human diseases including combined immunodeficiency (CID), atopy, and lymphoproliferation. However, the impact of CARD11 deficiency on human B-cell development, signaling, and function is incompletely understood. OBJECTIVES: This study sought to determine the cellular, immunological, and biochemical basis of disease for 2 unrelated patients who presented with profound CID associated with viral and fungal respiratory infections, interstitial lung disease, and severe colitis. METHODS: Patients underwent next-generation sequencing, immunophenotyping by flow cytometry, signaling assays by immunoblot, and transcriptome profiling by RNA-sequencing. RESULTS: Both patients carried identical novel pathogenic biallelic loss-of-function variants in CARD11 (c.2509C>T; p.Arg837∗) leading to undetectable protein expression. This variant prevented CBM complex formation, severely impairing the activation of nuclear factor-κB, c-Jun N-terminal kinase, and MALT1 paracaspase activity in B and T cells. This functional defect resulted in a developmental block in B cells at the naive and type 1 transitional B-cell stage and impaired circulating T follicular helper cell (cTFH) development, which was associated with impaired antibody responses and absent germinal center structures on lymph node histology. Transcriptomics indicated that CARD11-dependent signaling is essential for immune signaling pathways involved in the development of these cells. Both patients underwent hematopoietic stem cell transplantations, which led to functional normalization. CONCLUSIONS: Complete human CARD11 deficiency causes profound CID by impairing naive/type 1 B-cell and cTFH cell development and abolishing activation of MALT1 paracaspase, NF-κB, and JNK activity. Hematopoietic stem cell transplantation functionally restores impaired signaling pathways.

Fludarabine, Campath, and Low-Dose Cyclophosphamide (FCClow) with or without TBI Conditioning Results in Excellent Transplant Outcomes in Children with Severe Aplastic Anemia.

Various reduced-intensity conditioning regimens are in use for allogeneic hematopoietic cell transplant (HSCT) in patients with idiopathic severe aplastic anemia (SAA). We describe the use of fludarabine, Campath, and low-dose cyclophosphamide (FCClow) conditioning in 15 children undergoing related or unrelated donor transplants. Total body irradiation (TBI) of 2 Gy was added for unrelated donor HSCT. At a median follow-up of 2.3 years, the failure-free survival was 100%, with low rates of infection and toxicity. There was no occurrence of grade III to IV acute graft-versus-host disease (GVHD). All patients had full donor myeloid chimerism post-HSCT, even with mixed chimerism in the T cell lineage. The absence of chronic GVHD and long-term stable mixed donor T cell chimerism confirms immune tolerance following FCClow (± TBI) conditioned transplantation in children with SAA.

Nonmyeloablative Matched Sibling Donor Hematopoietic Cell Transplantation in Children and Adolescents with Sickle Cell Disease.

Sickle cell disease is a potentially debilitating hemoglobinopathy associated with early mortality. The only established curative therapy is hematopoietic cell transplantation (HCT) with a matched sibling donor. The National Institutes of Health nonmyeloablative regimen of alemtuzumab/300 cGy total body irradiation and prolonged sirolimus exposure for graft-versus-host disease (GVHD) prophylaxis was administered to 16 children and adolescents. Infused products were unmanipulated granulocyte colony stimulating factor mobilized peripheral blood stem cells. All patients achieved mixed donor-recipient engraftment with no cases of secondary graft failure to date. Two patients have donor myeloid chimerism in the range of 30% to 40%. No sickling crises post-HCT have been observed. Event-free and overall survival rates are 100% with median follow-up of 19.5 months. No cases of GVHD have been observed. Sirolimus weaning was possible in all but one eligible patient to date. Ongoing follow-up and a larger prospective clinical trial are required to determine the long-term safety and efficacy of this regimen in children.

Clinical and Genetic Risk Prediction of Subsequent CNS Tumors in Survivors of Childhood Cancer: A Report From the COG ALTE03N1 Study.

Purpose Survivors of childhood cancer treated with cranial radiation therapy are at risk for subsequent CNS tumors. However, significant interindividual variability in risk suggests a role for genetic susceptibility and provides an opportunity to identify survivors of childhood cancer at increased risk for these tumors. Methods We curated candidate genetic variants from previously published studies in adult-onset primary CNS tumors and replicated these in survivors of childhood cancer with and without subsequent CNS tumors (82 participants and 228 matched controls). We developed prediction models to identify survivors at high or low risk for subsequent CNS tumors and validated these models in an independent matched case-control sample (25 participants and 54 controls). Results We demonstrated an association between six previously published single nucleotide polymorphisms (rs15869 [ BRCA2], rs1805389 [ LIG4], rs8079544 [ TP53], rs25489 [ XRCC1], rs1673041 [ POLD1], and rs11615 [ ERCC1]) and subsequent CNS tumors in survivors of childhood cancer. Including genetic variants in a Final Model containing age at primary cancer, sex, and cranial radiation therapy dose yielded an area under the curve of 0.81 (95% CI, 0.76 to 0.86), which was superior ( P = .002) to the Clinical Model (area under the curve, 0.73; 95% CI, 0.66 to 0.80). The prediction model was successfully validated. The sensitivity and specificity of predicting survivors of childhood cancer at highest or lowest risk of subsequent CNS tumors was 87.5% and 83.5%, respectively. Conclusion It is possible to identify survivors of childhood cancer at high or low risk for subsequent CNS tumors on the basis of genetic and clinical information. This information can be used to inform surveillance for early detection of subsequent CNS tumors.

Adenovirus necrotizing hepatitis complicating atypical teratoid rhabdoid tumor.

Adenovirus-induced fulminant hepatitis is rare. It has been reported in children with primary immunodeficiency, following transplantation or while receiving chemotherapy for hematological malignancy. We present the case of an infant recovering from chemotherapy for atypical teratoid rhabdoid tumor (ATRT) in whom a diagnosis of hepatic necrosis due to adenovirus was made.

Hyaluronan synthase 3 variant and anthracycline-related cardiomyopathy: a report from the children's oncology group.

PURPOSE: The strong dose-dependent association between anthracyclines and cardiomyopathy is further exacerbated by the co-occurrence of cardiovascular risk factors (diabetes and hypertension). The high morbidity associated with cardiomyopathy necessitates an understanding of the underlying pathogenesis so that targeted interventions can be developed. PATIENTS AND METHODS: By using a two-stage design, we investigated host susceptibility to anthracycline-related cardiomyopathy by using the ITMAT/Broad CARe cardiovascular single nucleotide polymorphism (SNP) array to profile common SNPs in 2,100 genes considered relevant to de novo cardiovascular disease. RESULTS: By using a matched case-control design (93 cases, 194 controls), we identified a common SNP, rs2232228, in the hyaluronan synthase 3 (HAS3) gene that exerts a modifying effect on anthracycline dose-dependent cardiomyopathy risk (P = 5.3 × 10(-7)). Among individuals with rs2232228 GG genotype, cardiomyopathy was infrequent and not dose related. However, in individuals exposed to high-dose (> 250 mg/m(2)) anthracyclines, the rs2232228 AA genotype conferred an 8.9-fold (95% CI, 2.1- to 37.5-fold; P = .003) increased cardiomyopathy risk compared with the GG genotype. This gene-environment interaction was successfully replicated in an independent set of 76 patients with anthracycline-related cardiomyopathy. Relative HAS3 mRNA levels measured in healthy hearts tended to be lower among individuals with AA compared with GA genotypes (P = .09). CONCLUSION: Hyaluronan (HA) produced by HAS3 is a ubiquitous component of the extracellular matrix and plays an active role in tissue remodeling. In addition, HA is known to reduce reactive oxygen species (ROS) -induced cardiac injury. The high cardiomyopathy risk associated with AA genotype could be due to inadequate remodeling and/or inadequate protection of the heart from ROS-mediated injury on high anthracycline exposure.

A phase I study of histone deacetylase inhibitor, pracinostat (SB939), in pediatric patients with refractory solid tumors: IND203 a trial of the NCIC IND program/C17 pediatric phase I consortium.

BACKGROUND: Pracinostat (SB939) is a potent oral inhibitor of class 1, 2, and 4 histone deacetylases (HDAC). The adult recommended phase II dose (RP2D) is 60 mg po three times per week (t.i.w.) for 3 weeks every 4 weeks. This study assessed the toxicities and pharmacokinetics of pracinostat and determined the RP2D in children with refractory solid tumors. METHODS: Pediatric patients with refractory solid tumors were treated with oral pracinostat t.i.w. for 3 consecutive weeks, followed by 1 week off dosing. Three dose levels-25, 35, and 45 mg/m(2) were evaluated using a standard 3 + 3 cohort design. Pharmacokinetic (PK) studies were optional. RESULTS: Twelve patients were enrolled. The most common diagnosis was Ewing sarcoma. Most adverse events (AEs) were hematological with five (40%) patients experiencing grade 3 neutropenia. Non-hematological AEs were generally grade 1. No dose limiting toxicities occurred. More hematological and non-hematological AEs occurred at 45 mg/m(2) : Two of five patients experienced Grade 3 neutropenia and one each Grade 3 thrombocytopenia and leucopenia, Grade 1 fatigue and anorexia occurred in three. The RP2D was declared to be 45 mg/m(2) (comparable to an adult dose of 80 mg). One patient had a best response of stable disease (duration of 2.9 months). Three patients on 25 mg/m(2) and one each on 35 and 45 mg/m(2) participated in the PK study. No dose related changes in Cmax or AUC occurred. CONCLUSIONS: Pracinostat is reasonably well tolerated in children with refractory solid tumors. The RP2D is 45 mg/m(2) .

Color flow Doppler ultrasonography can distinguish caudal epidural injection from intrathecal injection.

BACKGROUND: Color flow Doppler ultrasonography has been used to confirm caudal epidural injection, but its ability to detect accidental intrathecal injection is unknown. We hypothesized that, when using color flow Doppler, the injection of fluid into the epidural space would result in turbulent flow which would appear as a burst of color while intrathecal injection would show an absence of a color flow Doppler signal. METHODS: Two groups of pediatric patients (up to 6 years of age) were prospectively enrolled for this observational study during a 2-month period. One group (group E) consisted of patients suitable for elective surgery using caudal epidural analgesia, and the other (group I) included patients receiving lumbar puncture for intrathecal chemotherapeutic injection. After induction of general anesthesia and placement of the patient in the lateral position, an 8 MHz curved array probe (Sonosite TITAN, Bothell, WA) was applied to obtain a transverse image of the lumbar region (L1-L3). Real-time images using color flow Doppler were obtained and recorded during initial injections of 2 consecutive (20 seconds apart) aliquots of 0.1 mL/kg medication of local anesthetic (0.25% bupivacaine) or chemotherapy drugs (mixture of methotrexate, cytarabine, and hydrocortisone) at a rate of 0.5 to 1.0 mL/s. After obtaining the study images, the rest of the medication was injected in standard fashion. A blinded anesthesiologist later evaluated the recorded images to determine a positive or negative result (positive = presence of turbulence as illustrated by a medley of color; negative = no turbulence or color). Sensitivity, specificity, and positive and negative predictive values were calculated for those patients who had successful analgesia (group E) and intrathecal (group I) injections. RESULTS: Forty recorded images from 41 patients (group E, n = 21; group I, n = 20) were included in the analysis. The observed sensitivity, specificity, positive predictive value, and negative predictive values were all 100%. The lower 95% confidence limits were 0.832. CONCLUSION: In the context of this study, color flow Doppler could differentiate epidural from intrathecal injection into the caudal space of children up to 6 years of age using a 0.1 mL/kg injection volume and injection rate of 0.5 to 1.0 mL/s.

Infantile myofibromatosis: report on a family with autosomal dominant inheritance and variable penetrance.

Infantile myofibromatosis (IM) is a benign tumor occurring in infants and young children. Familial IM is rare and the inheritance pattern of IM is unclear. We report on a unique family with four individuals having IM of varying degrees of severity with autosomal dominant inheritance pattern and variable penetrance.

DNA sequence context conceals α-anomeric lesions.

DNA sequence context has long been known to modulate detection and repair of DNA damage. Recent studies using experimental and computational approaches have sought to provide a basis for this observation. We have previously shown that an α-anomeric adenosine (αA) flanked by cytosines (5'CαAC-3') resulted in a kinked DNA duplex with an enlarged minor groove. Comparison of different flanking sequences revealed that a DNA duplex containing a 5'CαAG-3' motif exhibits unique substrate properties. However, this substrate was not distinguished by unusual thermodynamic properties. To understand the structural basis of the altered recognition, we have determined the solution structure of a DNA duplex with a 5'CαAG-3' core, using an extensive set of restraints including dipolar couplings and backbone torsion angles. The NMR structure exhibits an excellent agreement with the data (total R(X) <5.3%). The αA base is intrahelical, in a reverse Watson-Crick orientation, and forms a weak base pair with a thymine of the opposite strand. In comparison to the DNA duplex with a 5'CαAC-3' core, we observe a significant reduction of the local perturbation (backbone, stacking, tilt, roll, and twist), resulting in a straighter DNA with narrower minor groove. Overall, these features result in a less perturbed DNA helix and obscure the presence of the lesion compared to the 5'CαAC-3' sequence. The improved stacking of the 5'CαAG-3' core also affects the energetics of the DNA deformation that is required to form a catalytically competent complex. These traits provide a rationale for the modulation of the recognition by endonuclease IV.

Characterization of postsynaptic Ca2+ signals at the Drosophila larval NMJ.

Postsynaptic intracellular Ca(2+) concentration ([Ca(2+)](i)) has been proposed to play an important role in both synaptic plasticity and synaptic homeostasis. In particular, postsynaptic Ca(2+) signals can alter synaptic efficacy by influencing transmitter release, receptor sensitivity, and protein synthesis. We examined the postsynaptic Ca(2+) transients at the Drosophila larval neuromuscular junction (NMJ) by injecting the muscle fibers with Ca(2+) indicators rhod-2 and Oregon Green BAPTA-1 (OGB-1) and then monitoring their increased fluorescence during synaptic activity. We observed discrete postsynaptic Ca(2+) transients along the NMJ during single action potentials (APs) and quantal Ca(2+) transients produced by spontaneous transmitter release. Most of the evoked Ca(2+) transients resulted from the release of one or two quanta of transmitter and occurred largely at synaptic boutons. The magnitude of the Ca(2+) signals was correlated with synaptic efficacy; the Is terminals, which produce larger excitatory postsynaptic potentials (EPSPs) and have a greater quantal size than Ib terminals, produced a larger Ca(2+) signal per terminal length and larger quantal Ca(2+) signals than the Ib terminals. During a train of APs, the postsynaptic Ca(2+) signal increased but remained localized to the postsynaptic membrane. In addition, we showed that the plasma membrane Ca(2+)-ATPase (PMCA) played a role in extruding Ca(2+) from the postsynaptic region of the muscle. Drosophila melanogaster has a single PMCA gene, predicted to give rise to various isoforms by alternative splicing. Using RT-PCR, we detected the expression of multiple transcripts in muscle and nervous tissues; the physiological significance of the same is yet to be determined.

The treatment of pediatric Philadelphia positive (Ph+) leukemias in the imatinib era.

BACKGROUND: As the treatment of Philadelphia positive (Ph+) leukemias in the era of imatinib continues to evolve, the role of allogeneic hematopoietic cell transplantation (allogeneic-HCT) in first remission is becoming more unclear. PROCEDURE: Thirty-two pediatric centers across the United States and Canada were surveyed regarding current treatment practices for Ph+ acute lymphoblastic leukemia (ALL) and chronic myelogenous leukemia (CML). The survey addressed treatment approaches for Ph+ ALL and CML in terms of imatinib therapy and use of allogeneic-HCT. RESULTS: Twenty-three of the 32 centers returned the survey to provide a 72% response rate. Of the 27 physicians responding to the survey, 22 (81%) recommended a matched sibling donor (MSD) allogeneic-HCT, when available, in first remission for Ph+ ALL compared to 17/27 (63%) for patients with first chronic phase CML. There was universal agreement among survey responders regarding the use of imatinib upfront in Ph+ ALL and CML patients while 13 of 27 (48%) physicians reported using imatinib as maintenance therapy post-HCT for Ph+ ALL compared to 9 of 27 (33%) for CML. CONCLUSIONS: Although a treatment consensus did not exist based on the results of this small survey, current treatment practices for pediatric Ph+ ALL and CML appear to favor allogeneic-HCT when a MSD is available. The use of post-HCT imatinib as maintenance therapy to avoid relapse for either Ph+ ALL or CML remains uncertain and awaits future prospective studies.

Non-anaplastic peripheral t-cell lymphoma in childhood and adolescence: a Children's Oncology Group study.

BACKGROUND: Peripheral T-cell lymphomas (PTCL) other than anaplastic large cell lymphoma (ALCL) are rare in young patients. While a high proportion of adults with PTCL have poor risk disease, pediatric PTCL is not well characterized. This study examines the outcome of localized and advanced PTCL in pediatric patients treated in standardized fashion. PROCEDURE: We identified 20 pediatric patients diagnosed with PTCL whose tumor cells did not express CD30 and/or ALK, as determined by immunohistochemistry, between 1992 and 2000 on one of two treatment protocols for localized NHL (POG 9219) or advanced stage large cell lymphoma (POG 9315). All cases were centrally reviewed. RESULTS: The median age was 12.6 (range 0.7-16.9)-9 male and 11 female. Histological subtypes in the WHO Classification included PTCL, unspecified (12), extra-nodal NK/T-cell lymphoma of nasal type (4), subcutaneous panniculitis-like T cell lymphoma (1) and enteropathy-type T-cell lymphoma (1). Two cases exhibited both T-cell and histiocyte markers and were reclassified as histiocytic sarcoma per the WHO, although T-lineage remains possible. Of 10 patients with localized disease, only two relapsed and 9 survive. Of 10 patients with advanced disease, six relapsed and five (50%) survive. CONCLUSIONS: These results suggest that localized PTCL in children and adolescents is frequently cured with modern therapy, but that advanced stage cases may require novel therapy.

Effect of buffer and antioxidant on stability of a mercaptopurine suspension.

PURPOSE: The stability of standard and modified mercaptopurine suspensions when stored at room temperature and under refrigerated conditions to test the feasibility of increasing shelf life was studied. METHODS: A 50-mg/mL mercaptopurine suspension was compounded by adding simple syrup, cherry syrup, and sterile water for irrigation to triturated mercaptopurine tablets for the initial reference formulation. Three additional formulations were prepared by adding an antioxidant (ascorbic acid 10 mg), a buffer (sodium phosphate monobasic monohydrate 500 mg), and a combination of antioxidant and buffer to the reference formulation. Each compounded batch was divided into two parts and stored in amber bottles at room temperature (19-23 degrees C) or under refrigerated conditions (4-8 degrees C). Analysis through high-performance liquid chromatography determined mercaptopurine levels after three and seven days and weekly thereafter for at least two weeks after shelf life was reached under specified storage conditions. Solutions with at least 93% of the original mercaptopurine concentration and with no observable sign of aggregation or cake formation were considered stable. RESULTS: The reference suspension of mercaptopurine showed an acceptable physical and chemical stability of up to 5 weeks when stored at room temperature. The addition of ascorbic acid extended the shelf life of the compounded suspension to 11 weeks. However, the addition of sodium phosphate monobasic did not improve the stability of mercaptopurine in the suspension. The results showed a higher stability for all formulations after storage at room temperature compared with those stored in a refrigerator. CONCLUSION: A standard oral suspension of mercaptopurine contained an acceptable drug concentration for up to 5 weeks when stored at room temperature. The addition of ascorbic acid at a concentration of 0.1% w/v to the standard formulation increased the suspension's shelf life at room temperature to 11 weeks.