A small-molecule inhibitor of UBE2N induces neuroblastoma cell death via activation of p53 and JNK pathways.

Neuroblastoma (NB) is the most common extracranial neoplasm in children. In NB, loss of p53 function is largely due to cytoplasmic sequestration rather than mutation. Ubiquitin-conjugating enzyme E2 N (UBE2N), also known as Ubc13, is an E2 ubiquitin-conjugating enzyme that promotes formation of monomeric p53 that results in its cytoplasmic translocation and subsequent loss of function. Therefore, inhibition of UBE2N may reactivate p53 by promoting its nuclear accumulation. Here, we show that NSC697923, a novel UBE2N inhibitor, exhibits potent cytotoxicity in a panel of NB cell lines evidenced by its ability to induce apoptosis. In p53 wild-type NB cells, NSC697923 induced nuclear accumulation of p53, which led to its increased transcriptional activity and tumor suppressor function. Interestingly, in p53 mutant NB cells, NSC697923 induced cell death by activating JNK pathway. This effect was reversible by blocking JNK activity with its selective inhibitor, SP600125. More importantly, NSC697923 impeded cell growth of chemoresistant LA-N-6 NB cell line in a manner greater than conventional chemotherapy drugs doxorubicin and etoposide. NSC697923 also revealed in vivo antitumor efficacy in NB orthotopic xenografts. Taken together, our results suggest that UBE2N is a potential therapeutic target in NB and provide a basis for the rational use of UBE2N inhibitors like NSC697923 as a novel treatment option for NB patients.

USP7 inhibitor P22077 inhibits neuroblastoma growth via inducing p53-mediated apoptosis.

Neuroblastoma (NB) is a common pediatric cancer and contributes to more than 15% of all pediatric cancer-related deaths. Unlike adult tumors, recurrent somatic mutations in NB, such as tumor protein 53 (p53) mutations, occur with relative paucity. In addition, p53 downstream function is intact in NB cells with wild-type p53, suggesting that reactivation of p53 may be a viable therapeutic strategy for NB treatment. Herein, we report that the ubiquitin-specific protease 7 (USP7) inhibitor, P22077, potently induces apoptosis in NB cells with an intact USP7-HDM2-p53 axis but not in NB cells with mutant p53 or without human homolog of MDM2 (HDM2) expression. In this study, we found that P22077 stabilized p53 by inducing HDM2 protein degradation in NB cells. P22077 also significantly augmented the cytotoxic effects of doxorubicin (Dox) and etoposide (VP-16) in NB cells with an intact USP7-HDM2-p53 axis. Moreover, P22077 was found to be able to sensitize chemoresistant LA-N-6 NB cells to chemotherapy. In an in vivo orthotopic NB mouse model, P22077 significantly inhibited the xenograft growth of three NB cell lines. Database analysis of NB patients shows that high expression of USP7 significantly predicts poor outcomes. Together, our data strongly suggest that targeting USP7 is a novel concept in the treatment of NB. USP7-specific inhibitors like P22077 may serve not only as a stand-alone therapy but also as an effective adjunct to current chemotherapeutic regimens for treating NB with an intact USP7-HDM2-p53 axis.

Plasma and cerebrospinal fluid pharmacokinetics of MP470 in non-human primates.

PURPOSE: MP470 is a multi-targeted tyrosine kinase inhibitor with potent activity against mutant c-Kit, PDGFRα, Flt3, c-Met and c-Ret that is being evaluated as an anticancer agent. The plasma and cerebrospinal fluid (CSF) pharmacokinetics of MP470 were studied in a non-human primate model that is highly predictive of CSF penetration in humans. METHODS: Oral MP470, 300 mg, was administered to four non-human primates. Serial samples of blood were collected from four animals and CSF samples from three animals for pharmacokinetic studies. Plasma and CSF concentrations were measured using an LC-MS/MS assay. Both model-independent and model-dependent methods were used to analyze the pharmacokinetic data. RESULTS: Following a one-time oral dose of 300 mg, the MP470 plasma area under the curve (AUC) was 1,690 ± 821 nM h (mean ± SD). The half-life of MP470 in the plasma was 11.0 ± 3.4 h. There was no measurable MP470 in the CSF. CONCLUSIONS: Although CSF penetration is minimal, MP470 has demonstrated potent activity against cancer cell lines in vitro and in vivo, and further clinical investigation is warranted.

Dual-specificity phosphatase 26 is a novel p53 phosphatase and inhibits p53 tumor suppressor functions in human neuroblastoma.

Chemoresistance is a major cause of treatment failure and poor outcome in neuroblastoma. In this study, we investigated the expression and function of dual-specificity phosphatase 26 (DUSP26), also known as mitogen-activated protein kinase phophatase-8, in human neuroblastoma. We found that DUSP26 was expressed in a majority of neuroblastoma cell lines and tissue specimens. Importantly, we found that DUSP26 promotes the resistance of human neuroblastoma to doxorubicin-induced apoptosis by acting as a p53 phosphatase to downregulate p53 tumor suppressor function in neuroblastoma cells. Inhibiting DUSP26 expression in the IMR-32 neuroblastoma cell line enhanced doxorubicin-induced p53 phosphorylation at Ser20 and Ser37, p21, Puma, Bax expression as well as apoptosis. In contrast, DUSP26 overexpression in the SK-N-SH cell line inhibited doxorubicin-induced p53 phosphorylation at Ser20 and Ser37, p21, Puma, Bax expression and apoptosis. Using in vitro and in vivo assays, we found that DUSP26 binds to p53 and dephosphorylates p53 at Ser20 and Ser37. In this report, we show that DUSP26 functions as a p53 phosphatase, which suppresses downstream p53 activity in response to genotoxic stress. This suggests that inhibition of this phosphatase may increase neuroblastoma chemosensitivity and DUSP26 is a novel therapeutic target for this aggressive pediatric malignancy.

A distinct "side population" of cells with high drug efflux capacity in human tumor cells.

A subset of stem cells, termed the "side population" (SP), has been identified in several tissues in mammalian species. These cells maintain a high efflux capability for antimitotic drugs. We have investigated whether functionally equivalent stem cells also may be detected in human cancers. We initially examined primary tumor cells from 23 patients with neuroblastoma and cell lines derived from a range of other tumors. A distinct SP was found in neuroblastoma cells from 15 of 23 patients (65%). The SP was capable of sustained expansion ex vivo and showed evidence for asymmetric division, generating both SP and non-SP progeny. These cells also expressed high levels of ABCG2 and ABCA3 transporter genes and had a greater capacity to expel cytotoxic drugs, such as mitoxantrone, resulting in better survival. A SP also was detected in breast cancer, lung cancer, and glioblastoma cell lines, suggesting that this phenotype defines a class of cancer stem cells with inherently high resistance to chemotherapeutic agents that should be targeted during the treatment of malignant disease.

Targeting of G(D2)-positive tumor cells by human T lymphocytes engineered to express chimeric T-cell receptor genes.

Genetic engineering of human T lymphocytes to express tumor antigen-specific chimeric immune receptors is an attractive means for providing large numbers of effector cells for adoptive immunotherapy while bypassing major mechanisms of tumor escape from immune recognition. We have applied this strategy to the targeting of a G(D2)-positive tumor, neuroblastoma, which is the commonest extracranial solid tumor of childhood. Chimeric immune receptors were generated by joining an extracellular antigen-binding domain derived from either of the 2 ganglioside G(D2)-specific antibodies sc7A4 and sc14.G2a to a cytoplasmic signaling domain. The variable domains of hybridoma antibody 14.G2a were cloned and selected using a phage display approach. Upon coincubation with G(D2)-expressing tumor cell targets, human T lymphocytes transduced with recombinant retroviruses encoding chimeric receptors based on sc14.G2a, but not sc7A4, secreted significant levels of cytokines in a pattern comparable to the cytokine response obtained by engagement of the CD3 receptor. T cells transduced with the sc14.G2a-based chimeric T-cell receptors also displayed specific lysis of G(D2)-positive neuroblastoma cells, which was blocked in the presence of monoclonal antibody 14.G2a. In the absence of nonspecific stimulation of transduced cells, their functionality declined over time and antigenic stimulation of the chimeric receptor alone did not induce commitment to proliferation. These results support the feasibility of redirecting human T lymphocytes to a tumor-associated ganglioside epitope but emphasize that successful chimeric receptor-mediated adoptive immunotherapy will require additional strategies that overcome functional inactivation of gene-modified primary T lymphocytes.

Major histocompatibility complex-restricted lysis of neuroblastoma cells by autologous cytotoxic T lymphocytes.

Vigorous host immune reactivity to neuroblastoma may correlate with better prognosis, but identification of human cytotoxic T-lymphocyte (CTL) responses has been relatively unsuccessful. We generated neuroblastoma-reactive CTL lines from two human leukocyte antigen (HLA) A2+ neuroblastoma patients by stimulation of peripheral blood lymphocytes (PBLs) with irradiated autologous tumor cells pretreated with interferon-gamma in the presence of low concentrations of interleukin-2 (5 U/mL). These lines lyse autologous tumor cells but do not kill HLA mismatched allogeneic tumor cells, Epstein-Barr virus-transformed autologous B cells, or standard natural killer cell targets. Cytotoxic T lymphocytes generated from one patient recognize tumor cells from several HLA-A2 matched children, although the other patient's CTLs do not kill tumor cells from other HLA-A2+ individuals. Pretreatment of CTLs or target cells with appropriate standard monoclonal antibodies demonstrates that these CTLs are major histocompatibility complex class I (HLA-A2) restricted and that the effector cell population is CD8+. Our findings suggest that these tumor cells express at least one common HLA-A2 restricted antigen and at least one unique private epitope. Autologous tumor-specific CTLs can be readily generated from patients' PBLs and maintained in long-term culture using standard techniques.

Successful use of Tesio catheters in pediatric patients receiving chronic hemodialysis.

Semipermanent venous catheters remain the most commonly used access for chronic hemodialysis (HD) in pediatric patients. The recent availability of Tesio catheters in 7 and 10 F has expanded available HD catheter options for children and adolescents. We report our experience with Tesio catheter survival, complications, and effect on dialysis adequacy in comparison to standard dual-lumen (DL) catheters in our pediatric HD patients. Demographic data were similar between the two groups. Overall actuarial survival was significantly longer for Tesio versus DL catheters (46% versus 0% at 1 year; P = 0.003). A comparison of smaller catheters (7 F Tesio catheter, 8 or 10 F DL catheter) showed that smaller Tesio catheters had a significantly longer survival (median survival, 244 versus 13 catheter-days; P < 0.01). Tesio 10 F catheters also survived significantly longer than the larger 11.5 and 12 F DL catheters (P < 0.02). Catheter sepsis occurred less frequently with Tesio catheters (one episode/20 catheter-months) than DL catheters (one episode/5 catheter-months) despite the longer duration of Tesio catheters. Adequate dialysis (single-pool Kt/V > 1.2) was delivered with the same frequency, but for a longer duration with Tesio catheters (76% +/- 32% over 100 monthly measurements versus DL catheter, 57% +/- 45% over 54 monthly measurements). Our clinical practice was to replace cuffed catheters when adequate dialysis could not be delivered. We conclude that Tesio catheters provide superior performance compared with DL catheters in terms of catheter survival, infection rates, and duration of adequate performance.

Surgery for ovarian masses in infants, children, and adolescents: 102 consecutive patients treated in a 15-year period.

BACKGROUND/PURPOSE: Ovarian pathology, although rare in children, must be included in the differential diagnosis of all girls who present with abdominal pain, an abdominal mass, or precocious puberty. METHODS: To improve clinical appreciation of these lesions, the authors reviewed the presentation, evaluation, and outcome of all patients with ovarian pathology surgically treated at their institution since 1985. RESULTS: One hundred two girls (aged 9.8 +/- 5.5 years; range, 2 days to 20 years) underwent 106 separate ovarian operations (43 salpingo-oophorectomies, 21 oophorectomies, 33 ovarian cystectomies, and 9 ovarian biopsies). Of those presenting with acute abdominal pain (n = 59), 25 (42%) had ovarian torsion (14 associated with a mature teratoma), and only 1 (2%) had a malignant tumor. In contrast, of those presenting with an abdominal mass (n = 23), 6 (26%) had malignancies. There was no age difference between those with benign disease (9.9 +/- 5.6 years; n = 96) and those with malignant tumors (8.6 +/- 3.9 years, n = 10). Nine children had 10 operations for presumed malignant tumors (3 dysgerminomas, 2 immature teratomas with foci of yolk sac tumor, 2 juvenile granulosa cell tumors, 1 yolk sac tumor, and 1 Sertoli-Leydig cell tumor). These patients all had unilateral salpingo-oophorectomy, 4 had chemotherapy, and all are now disease free at 8.4 +/- 4.1 years follow-up. CONCLUSION: Ovarian pathology remains a rare indication for surgery in girls less than 20 years of age. Because most of these lesions are benign, ovarian-preserving operations should be performed whenever feasible.

Selection of human antitumor single-chain Fv antibodies from the B-cell repertoire of patients immunized against autologous neuroblastoma.

BACKGROUND: We used phage display technology to clone human recombinant antitumor antibodies from the antibody repertoire of neuroblastoma patients immunized with cytokine-gene transduced tumor cells. PROCEDURE: Lymphocytes obtained from neuroblastoma patients either at diagnosis or after immunization with an autologous interleukin-2 gene transduced tumor vaccine were used to construct two human single-chain Fv (scFV) phage libraries. Tumor-reactive phage were characterized using ELISA, flow cytometry, and sequencing analysis. RESULTS: The initial screening after panning on neuroblastoma cells yielded a substantially higher proportion of selectivity tumor-binding phage clones derived from the immunized patients library (12.9%) than from the unvaccinated patients library (0.8%). The antibodies stained the cells from several additional pediatric malignancies, including Ewing sarcoma and rhabdomyosarcoma, in the absence of binding to any normal tissue cultures or epithelial tumor cell lines. The pattern of reactivity was different from that of antibodies recognizing other widely distributed neuroblastoma-associated antigens, suggesting recognition of a novel shared tumor antigen. CONCLUSION: The human recombinant scFV antibodies reported here appear to represent a tumor-specific B-cell response induced by autologous tumor immunization and are potentially useful targeting moieties for the treatment of selected childhood tumors.

Peritoneal drainage as definitive treatment for neonates with isolated intestinal perforation.

BACKGROUND/PURPOSE: To better define the indications for peritoneal drainage (PD) in premature babies with intestinal perforation, the authors reviewed their experience with this procedure in a tertiary neonatal intensive care setting. METHODS: The charts of all neonates who underwent PD as initial treatment for intestinal perforation between 1996 and 1999 were reviewed. Those patients with pneumatosis intestinalis on abdominal radiograph had perforated necrotizing enterocolitis (NEC) diagnosed; whereas, those infants with no pneumatosis had isolated intestinal perforation diagnosed. The clinical characteristics and outcomes of these 2 groups were compared. RESULTS: Twenty-one premature neonates had primary PD between 1996 and 1999, 10 for isolated intestinal perforation and 11 for perforated NEC. Patients with isolated intestinal perforation had lower birth weights (708 v 949 g; P < .05), were less likely to have started feedings (30% v 91%, P < .05), and the perforation developed at an earlier age (10.6 v 28.0 d, P < .05) compared with the patients who had perforated NEC. Only 2 of 10 infants with isolated perforation required subsequent laparotomy (at 10 weeks for stricture and 12 weeks for a persistent fistula). For these patients, the long-term survival rate was 90%. In contrast, 8 of 11 infants with perforated NEC required laparotomy, and although the 30-day survival rate was 64%, the long-term survival rate was only 27%. CONCLUSIONS: Peritoneal drainage provides successful and definitive treatment for most premature babies with isolated intestinal perforation. For neonates with perforation caused by NEC, peritoneal drainage may provide temporary stabilization, but most of these infants require subsequent laparotomy, and few survive.

Lysis of MYCN-amplified neuroblastoma cells by MYCN peptide-specific cytotoxic T lymphocytes.

The effectiveness of cell-mediated immunotherapy for cancer can be limited by loss-of-antigen mutations that occur during tumor growth. In neuroblastoma, amplification of the MYCN oncogene correlates with rapid tumor progression and a poor prognosis overall. We propose that the MYCN protein, the high-level expression of which is required for maintenance of the malignant phenotype, would be an ideal target for vaccine therapy. The MYCN-derived S9K peptide (amino acids 7-15; STMPGMICK), which contains an HLA-A1 binding motif, was used to generate CTLs from the peripheral blood lymphocytes of an HLA-A1+ healthy donor and an HLA-A1+ patient with MYCN-amplified neuroblastoma These CTL lines specifically lysed HLA-matched, MYCN-amplified neuroblastoma tumor cells. They did not lyse either HLA-mismatched, MYCN-amplified, or matched/nonmatched, non-MYCN-amplified tumor cells. The CTL activity was inhibited by a monoclonal antibody to a class I HLA monomorphic determinant but not by one specific for HLA class II, consistent with a class I-restricted mechanism of cytotoxicity. Antibodies to CD8, but not those to CD4, also inhibited CTL activity, identifying CD8+ lymphocytes as the effector cell population. These results show that MYCN-derived peptides can serve as tumor-specific antigens and suggest a rational approach to cell-mediated immunotherapy for MYCN-amplified neuroblastoma.

Pharmacokinetics and cerebrospinal fluid penetration of CI-994 (N-acetyldinaline) in the nonhuman primate.

CI-994 is a substituted benzamide derivative that has demonstrated significant antitumor activity in vitro and in vivo against a broad spectrum of murine and human tumor models. Its mechanism of action is still unknown but seems to be novel compared with existing anticancer drugs. We studied the plasma and cerebrospinal fluid (CSF) pharmacokinetics of CI-994 in nonhuman primates. Three animals (total 4 doses) received an 80 mg/m2 dose of CI-994 administered over 20 min, and one animal received a dose of 100 mg/m2. Serial plasma and fourth ventricular CSF samples were obtained from 0 to 4320 min after administration of the 80-mg/m2 dose, and only plasma samples were obtained after the 100-mg/m2 dose. CI-994 was measured using a previously validated reverse-phase high-performance liquid chromatography assay. Elimination of CI-994 from plasma was triexponential (4 of 5 cases) or biexponential (1 of 5 cases), with a terminal half life (t1/2) of 7.4 +/- 2.5 h, volume of distribution of 15.5 +/- 1.8 L/m2, and clearance of 40 +/- 6 ml/min/m2. The area under the concentration-time curve (AUC) for the 80-mg/m2 dose was 125 +/- 17 microM x hr. CI-994 was first detected in CSF at the completion of the i.v. infusion. Peak concentrations of CI-994 in CSF were 3.4 +/- 0.3 microM. Elimination from CSF was monoexponential (2 of 4 cases) or biexponential (2 of 4 cases) with a terminal t1/2 in CSF of 12.9 +/- 2.5 h and AUC of 55 +/- 18 microM x hr. The AUC(CSF):AUCplasma ratio was 43 +/- 10%. This study demonstrates that there is excellent CSF penetration of CI-994 after i.v. administration. Additional studies are needed to evaluate the potential role of CI-994 in the treatment of central nervous system neoplasms.

Postoperative ad lib feeding for hypertrophic pyloric stenosis.

PURPOSE: The aim of this study was to compare three methods of postoperative feeding after pyloromyotomy for hypertrophic pyloric stenosis (HPS). METHODS: The authors reviewed retrospectively the charts of 308 patients who underwent pyloromyotomy for HPS from 1984 to 1997. Nineteen patients had prolonged hospitalization for other reasons and were excluded from the study, leaving 289 patients for analysis. All procedures were performed by a single group of pediatric surgeons. The individual preferences of these surgeons resulted in three different feeding schedules: R, strictly regimented (>12 hours nothing by mouth, then incremental feeding over > or =24 hours), I, intermediate (>8 hours nothing by mouth, then incremental feeding over <24 hours), or A, ad lib (< or =4 hours nothing by mouth, with or without a single small feeding, then ad lib feedings). RESULTS: Of the 289 patients, 248 (80.5%) were boys. The average age of the patients was 5.64 weeks (range, 1 to 21 weeks). A total of 265 of 289 (92%) were full term. Thirty-nine of 289 (13.5%) had a family history positive for pyloric stenosis. A total of 104 of 289 (36%) were first-born infants, 89 of 289 (31%) were second born. The diagnosis of pyloric stenosis was made by a combination of physical examination findings and diagnostic image for most patients. An "olive" was palpated in 60.6% of the patients. Sixty percent (60.4%) of patients had an upper gastrointestinal series performed, and 42.5% were examined by ultrasonography. Overall, 53% of the patients had postoperative emesis. Only 3.5% had emesis that persisted greater than 48 hours after surgery. Patients fed ad lib after pyloromyotomy had slightly more emesis (2.2 A v. 1.2 R, and 0.7 I episodes, P = .002), but tolerated full feedings sooner than patients fed with a regimented or intermediate schedule. No patient required additional therapy or readmission after tolerating two consecutive full feedings, suggesting that this might be a suitable discharge criterion for most patients with HPS.

Gastrointestinal autonomic nerve tumors in the pediatric population: a report of four cases and a review of the literature.

BACKGROUND: Gastrointestinal autonomic nerve tumors (GANTs) are a subpopulation of gastrointestinal stromal tumors (GISTs) that are characterized by ultrastructural features resembling enteric autonomic nerve cells, without epithelial, Schwannian, or smooth muscle differentiation. Delineation of the clinicopathologic features of GANT in the pediatric population is lacking. METHODS: The clinicopathologic and outcome data for four pediatric patients with GANT are presented. The data from these patients and four previously reported pediatric patients are summarized and compared with data for GANT in adults. RESULTS: All four cases occurred in females at a mean age of 12.5 years. The primary tumor site was the stomach in all cases, and the mean tumor size was 6.3 cm. Immunocytochemical and ultrastructural examination were essential in distinguishing GANT from GIST in all cases by identifying features of neural origin (neuron specific enolase in all four cases, NFP in three cases, S-100 in two cases, dense core neurosecretory granules in all four cases, and neuritelike processes in all four cases), while failing to identify features of myogenic origin (no desmin, smooth muscle actin, myofilaments, or dense bodies were found in any of the cases). Primary treatment was surgical, with chemotherapy administered to 1 patient at the time of recurrence. All patients are alive after a mean follow-up of 60 months (range, 8 months to 9 years). CONCLUSIONS: Similarities of pediatric GANT to GANT in adults include the need for a high index of suspicion for diagnosis; comparable histopathologic, immunohistochemical, and ultrastructural features; and surgery as the primary therapy. Distinguishing features in children may be a prevalence among females in the second decade, a predominance of smaller gastric tumors, and a positive prognostic value of younger age.

Laparoscopic evaluation of the pediatric inguinal hernia--a meta-analysis.

BACKGROUND/PURPOSE: For over 50 years there has been debate over how to manage the contralateral groin in children who present with a unilateral inguinal hernia. Many preoperative and intraoperative tools to diagnose a contralateral patent processus vaginalis or true inguinal hernia have been described. In 1992 laparoscopy was introduced as a new diagnostic test. Although multiple series have assessed this new tool, none of them have been able to statistically show that laparoscopy is effective in assessing the contralateral groin. By combining all published studies and using the technique of meta-analysis, intraoperative laparoscopy can be shown to be effective in diagnosing a contralateral patent processus vaginalis in children undergoing unilateral inguinal herniorrhaphy. METHODS: All available studies of children with a unilateral hernia who had exploration of the contralateral groin by laparoscopy were reanalyzed. Sensitivity and specificity of laparoscopy was determined using open exploration or development of a metachronous hernia as the gold standard. RESULTS: Nine hundred sixty-four patients were suitable for analysis. A contralateral hernia was seen on laparoscopy in 376 patients. All of these patients underwent open contralateral exploration. A patent processus vaginalis or true hernia sac was found in 373. The sensitivity of laparoscopy was 99.4% (95% confidence interval 97.87 to 99.91). Five hundred eighty-eight patients had a laparoscopy with negative results. Sixty-two of these patients then had open contralateral exploration. In one case, a patent processus vaginalis was found; the other 61 patients underwent exploration with negative results. In the remaining 526 laparoscopy-negative patients, follow-up (1 month to 3 years) was used to see if a contralateral hernia developed. A metachronous hernia developed in one of the 526 patients. The specificity of laparoscopy was 99.5% (95% confidence interval 98.39 to 99.87). Laparoscopy added an average of 6 minutes to the surgical time and was accurate regardless of the technique. There were two minor complications related to laparoscopy and no deaths. CONCLUSIONS: Laparoscopy may be the ideal tool to diagnose a contralateral patent processus vaginalis intraoperatively. It is sensitive, specific, fast, and safe. Although the presence of a patent processus does not imply that the patient will go on to develop a metachronous hernia, identifying and ligating a patent processus should certainly prevent the development of an indirect inguinal hernia.

Ventricular tachycardia during repair of gastroschisis.

Ventricular tachycardia has been reported after blunt cardiac trauma in both children and adults. However, to the best of our knowledge, there are no reports of sudden onset of ventricular tachycardia at the time of surgical closure of gastroschisis. This case describes a patient with gastroschisis who developed a medically resistant ventricular tachycardia upon reduction of the gastroschisis.

Meta-analysis of the risk of metachronous hernia in infants and children.

BACKGROUND: Inguinal herniorrhaphy is the most common general surgical procedure performed in children. The presence of a contralateral patent processus vaginalis forms the basis of the recommendation for contralateral exploration in patients undergoing unilateral herniorrhaphy. However, a patent processus vaginalis does not necessarily go on to become a clinically apparent inguinal hernia. METHODS: All published pediatric series, in which patients underwent unilateral inguinal hernia repair and were evaluated for the development of a metachronous hernia, were included. The incidence of and risk factors associated with development a metachronous hernia were evaluated with meta-analysis. RESULTS: There were 15,310 patients ranging in age from birth to 16 years, including premature infants. Of these, 1,062 patients (7%) developed a metachronous hernia. Gender and age were not risk factors. There was an 11% risk of metachronous hernia if the original hernia was on the left side, a risk that was 50% greater than if the original hernia was on the right. Of patients who developed a metachronous hernia, 90% did so within 5 years. The complication rate of metachronous hernia was 0.5%. CONCLUSION: There is no role for routine contralateral groin exploration. High-risk infants and children, especially those who undergo left inguinal herniorrhaphy, may benefit from contralateral groin exploration. If a patent processus vaginalis is found, it should be ligated. Patients who do not undergo contralateral groin exploration should be followed up for 5 years.

Infradiaphragmatic extralobar pulmonary sequestration masquerading as an intra-abdominal, suprarenal mass.

Three infants were found to have infradiaphragmatic masses by prenatal ultrasound. Postnatal imaging studies confirmed the presence of these masses, which were suspected of being intra-abdominal malignancies (neuroblastoma). The other principal differential diagnosis was extralobar pulmonary sequestration (EPS). Intraoperative findings were consistent with EPS, which was confirmed by histologic examination. We present these three infants, review the literature, and discuss the evaluation and treatment of infradiaphragmatic EPS.

Nonoperative initial management versus silon chimney for treatment of giant omphalocele.

Giant omphalocele is a major clinical challenge for pediatric surgeons. Whereas small- to medium-sized defects can be repaired primarily, larger omphaloceles cannot be closed at birth because the liver and small bowel have lost the right of domain to the abdomen. Two divergent strategies have evolved for treating these giant defects: (1) use of a silon chimney with gradual reduction of the contents of the sac, and (2) initial nonoperative management (epithelialization) of the omphalocele followed by repair of the residual ventral hernia. In an 18-year retrospective study, we have reviewed our experience with these treatment methods. Ninety-four infants underwent treatment for omphalocele between 1975 and 1993. Primary closure (PC) was possible in 55 patients, silon chimney (SC) was used in 15, and 7 had nonoperative management (NM) with epithelialization. In the remaining 17 infants, surgery was believed to be inappropriate because of the lethality of their associated anomalies. Major (but potentially survivable) anomalies were present in 26% of PC, 13% of SC, and 71% of the NM group patients. The majority of the liver was present in 73% of SC- and 86% of NM-treated omphaloceles. There was a decrease in length of stay, time to enteral feeding, and mortality over the 18-year period. However, those patients whose defects could not be closed primarily had consistently longer hospital stays. This was particularly true for the SC patients. The decreased use of total parenteral nutrition seems to reflect a shift from SC to NM rather than a decrease in the interval to full enteral feeding in any given treatment group over time.(ABSTRACT TRUNCATED AT 250 WORDS)