Samuel Z. Soffer

Nonoperative management of symptomatic urachal anomalies

INTRODUCTIONnSymptomatic urachal anomalies are rare disorders that consist of urachal remnants or fistulas with or without an associated cyst. Traditionally, when a urachal anomaly was recognized, operative excision was performed. There has been a shift toward the nonoperative management of urachal anomalies at many centers, although there is little in the literature to support this practice.nnnMETHODSnA retrospective chart review of patients with urachal anomalies was performed from January 2002 to March 2008. Children with a draining umbilicus and no radiographic or surgical confirmation of a urachal anomaly were excluded.nnnRESULTSnFifteen patients with symptomatic urachal anomalies were identified. The average age was 3.5 years (4 weeks to 14 years). Symptoms included umbilical drainage (n = 10), abdominal pain (n = 6), omphalitis (n = 4), intraabdominal mass (n = 3), dysuria (n = 1), recurrent urinary tract infections (n = 1), and fever (n = 4). The diagnosis was confirmed by ultrasound (n = 13) and/or computed tomographic scan (n = 4). The surgically treated cases included 7 urachal cysts (5 uninfected, 2 infected) and 1 patent urachal fistula. Mean follow-up is 37 months, and there have been no reported recurrences. Those treated without surgical excision included 4 patent urachal fistulas (mean follow-up, 20 months-no recurrences) and 3 infected urachal cysts (percutaneous drainage [n = 2] and laparoscopic drainage [n = 1]-no recurrences on ultrasound at 26 months).nnnCONCLUSIONnNonoperative management of urachal anomalies is a reasonable approach and may be extended to infected urachal cysts after initial drainage. Infected cysts that are adequately drained seem to obliterate with time. Modern ultrasonography facilitates thorough follow-up. We propose a treatment algorithm for the management of suspected urachal anomalies.

Laparoscopic inguinal hernia inversion and ligation in female children: a review of 173 consecutive cases at a single institution.

PURPOSEnLaparoscopic inguinal hernia inversion and ligation (LIHIL) is a method of hernia repair in which the hernia sac is inverted into the peritoneal cavity and subsequently ligated and excised. Since 2003, 5 surgeons at our institution have been performing LIHIL in girls.nnnMETHODSnA retrospective review of inguinal hernias in girls from 2003 to 2009 was performed.nnnRESULTSnTwo hundred forty-one LIHILs were performed on 173 girls. The average age of children undergoing LIHIL was 57 months (range, 1-210 months). Fifteen cases were ex-premature babies (8.7%). Of the unilateral inguinal hernias, 34% were found to have bilateral hernias intraoperatively, and these were repaired at the same operation. There have been no intraoperative complications. Postoperatively, there have been no wound complications and 2 recurrences (0.83%). Both recurrences were repaired using an open technique.nnnCONCLUSIONSnLaparoscopic inguinal hernia inversion and ligation is a safe and effective operation in girls with a low recurrence rate. Benefits of this procedure include diagnosis and repair of the contralateral side using the same incisions, diagnosis of androgen insensitivity and other dysgenic situations, and excellent cosmesis. This operation is a straightforward technique that can be performed by most pediatric surgeons with basic laparoscopic skills.

Celecoxib inhibits invasion and metastasis via a cyclooxygenase 2–independent mechanism in an in vitro model of Ewing sarcoma

BACKGROUND/INTRODUCTIONnPreviously, we reported that celecoxib, a cyclooxygenase-2 (COX-2) inhibitor, prevented lung metastases but did not affect tumor growth in a model of Ewing sarcoma. Cyclooxygenase-2 inhibition has been proposed as an antimetastatic strategy. The mechanism of action remains unclear.nnnMETHODSnEwing sarcoma cells were suspended in a soluble basement membrane extract (Cultrex; Trevigen, Inc, Gaithersburg, MD) and supplemented with celecoxib or with rofecoxib, a second COX-2 inhibitor, above a filter. Controls received solvent. After 48 hours, the cells that invaded through the basement membrane and filter were stained and counted. The assay was repeated with the addition of 500-nM prostaglandin E2 (PGE(2)).nnnRESULTSnInvasion was significantly decreased in the celecoxib groups compared with the control. The addition of PGE(2) did not overcome celecoxib inhibition. Rofecoxib did not significantly affect invasion compared with control either with or without PGE(2).nnnCONCLUSIONSnCelecoxib significantly inhibits invasion of Ewing sarcoma cells in vitro. Prostaglandin E2, a downstream product of COX-2, did not reverse in vitro inhibition, suggesting that celecoxib acts through a COX-2-independent mechanism. This is further supported by the failure of rofecoxib to inhibit invasion despite more selectively inhibiting COX-2.

Selective inhibition of cyclooxygenase-2 suppresses metastatic disease without affecting primary tumor growth in a murine model of Ewing sarcoma

BACKGROUND/PURPOSEnMammalian target of rapamycin suppression by rapamycin inhibits tumor growth and neovascularization via cyclooxygenase-2 (COX-2) downregulation with no effect on lung metastases. We hypothesize that combining a selective COX-2 antagonist (celecoxib) with rapamycin would decrease lung metastases.nnnMETHODSnEwing sarcoma cells (SK-NEP-1) were surgically implanted into the left kidney of athymic mice (n = 40). The mice were divided into 4 treatment groups (control, rapamycin only, celecoxib only, and combination) and then killed at 6 weeks. Primary tumors were weighed. Vasculature was examined using lectin angiography and immunohistochemistry, and lung metastases were examined using H&E and CD99 immunostaining. Tumor weight and lung metastases were analyzed.nnnRESULTSnMean primary tumor weights were significantly reduced in the rapamycin-treated groups but not in the celecoxib-only group. Lectin angiography and endothelial markers immunostaining showed markedly decreased vascularity in the rapamycin-treated groups but not in the celecoxib-only group. Celecoxib-treated groups showed significantly fewer mice with lung metastases than non-celecoxib-treated groups.nnnCONCLUSIONnCelecoxib prevents lung metastasis in a murine model of Ewing sarcoma with no effect on tumor size or neovascularization. Cyclooxygenase-2 may represent a future potential target for metastatic disease prevention.

Neonatal esophageal perforation: nonoperative management

BACKGROUNDnEsophageal perforation is a rare complication of enteric instrumentation in neonates. Enteric tube placement in micro-preemies poses a particular hazard to the narrow lumen and thin wall of the developing esophagus. The complication may be difficult to recognize or misdiagnosed as esophageal atresia, and is associated with considerable mortality. Historically, management of this life-threatening iatrogenic disease was operative, but trends have shifted toward nonoperative treatment. Here, we review neonatal esophageal perforation at our own institution for management techniques, risk factors, and outcomes.nnnMATERIALS AND METHODSnSeven neonatal patients with esophageal perforation were identified and charts reviewed for demographics, comorbidities, etiology of perforation, diagnostic modalities, management decisions, complications, and outcomes.nnnRESULTSnMean gestational age was 27.2 ± 4.0 wk, and weight at diagnosis was 892 ± 674 g. All seven patients had esophageal perforation resulting from endotracheal or enterogastric intubation and were managed nonoperatively. Treatment included removal of the offending tube, nil per os, and antibiotics. Five patients required additional interventions: four tube thoracostomies for pneumothoraces and one peritoneal drain for pneumoperitoneum. Three patients died because of sequelae of prematurity (intraventricular hemorrhage, necrotizing enterocolitis, and sepsis). One patient was diagnosed as having esophageal atresia; esophagoscopy before surgical repair established the correct diagnosis.nnnCONCLUSIONSnNeonates, particularly those under 1500 g, are at substantial risk for iatrogenic esophageal perforation during enterogastric intubation. Nonoperative management may be a safe initial strategy in the neonatal setting, but more aggressive interventions may ultimately be required. Despite recent improvement in early recognition of this injury, misdiagnosis still occurs.

Cyclooxygenase 2 mediates the antiangiogenic effect of rapamycin in Ewing sarcoma

BACKGROUNDnRapamycin can inhibit tumor growth and angiogenesis in various human cancers. Cyclooxygenase 2 (COX-2) is involved in the angiogenic process. We hypothesized that the antiangiogenic effect of rapamycin may be mediated by suppression of COX-2.nnnMETHODSnEwing sarcoma (ES) cells were implanted in athymic mice. Selected animals were treated with rapamycin for 5 weeks. Tumor vascularity was assessed by lectin perfusion angiography and immunohistochemistry. Phosphorylation of mammalian target of rapamycin pathway proteins was determined by Western blot analysis. Staining of COX-2 protein was determined by immunohistochemistry, and expression of COX-2 messenger RNA levels was assessed with quantitative real-time (RT) polymerase chain reaction.nnnRESULTSnMean tumor weights were significantly reduced in the treated group (5.43 g +/- 1.43 SEM vs 0.49 g +/- 0.15 SEM, P < .003). There was abundant vasculature in the control group and blunted vascularity in the treated xenografts. The phosphorylation of p70s6k and Akt was not inhibited in the rapamycin-treated tumors. Cyclooxygenase 2 was suppressed in the treated xenografts at both the protein and messenger RNA levels.nnnCONCLUSIONnLow-dose rapamycin inhibits tumor growth and angiogenesis in human ES without inhibiting the phosphorylation of p70s6k and Akt. Cyclooxygenase 2 levels are inhibited by low-dose treatment of ES with rapamycin. Cyclooxygenase 2 suppression may mediate the antiangiogenic effect of rapamycin in Ewing sarcoma.

Esophageal carcinoma in children and adolescents.

Background: Esophageal cancer is rare in children and is limited to isolated case reports. We describe 2 cases of esophageal carcinoma (1 case each of squamous cell carcinoma and adenocarcinoma) and present literature review of esophageal carcinoma in childhood. Observations: Both of our patients had common symptoms of progressive dysphagia and significant weight loss at presentation. We were unable to identify any specific predisposing factors for either adenocarcinoma (caustic ingestion, reflux disease, Barrett esophagus) or squamous cell carcinoma (caustic ingestion, inherited bone marrow failure syndromes). Both patients responded poorly to chemotherapy and died of progressive disease. Conclusions: On account of the rarity of esophageal carcinoma in this age group, there are no management guidelines for the pediatric oncologist. There is a strong need for collaborative efforts between adult and pediatric oncologists to establish cooperative diagnostic and therapeutic protocols for successful management of rare pediatric tumors like esophageal carcinoma.

The Macrophage Inhibitor CNI-1493 Blocks Metastasis in a Mouse Model of Ewing Sarcoma through Inhibition of Extravasation

Metastatic Ewing Sarcoma carries a poor prognosis, and novel therapeutics to prevent and treat metastatic disease are greatly needed. Recent evidence demonstrates that tumor-associated macrophages in Ewing Sarcoma are associated with more advanced disease. While some macrophage phenotypes (M1) exhibit anti-tumor activity, distinct phenotypes (M2) may contribute to malignant progression and metastasis. In this study, we show that M2 macrophages promote Ewing Sarcoma invasion and extravasation, pointing to a potential target of anti-metastatic therapy. CNI-1493 is a selective inhibitor of macrophage function and has shown to be safe in clinical trials as an anti-inflammatory agent. In a xenograft mouse model of metastatic Ewing Sarcoma, CNI-1493 treatment dramatically reduces metastatic tumor burden. Furthermore, metastases in treated animals have a less invasive morphology. We show in vitro that CNI-1493 decreases M2-stimulated Ewing Sarcoma tumor cell invasion and extravasation, offering a functional mechanism through which CNI-1493 attenuates metastasis. These data indicate that CNI-1493 may be a safe and effective adjuvant agent for the prevention and treatment of metastatic Ewing Sarcoma.

Intrathoracic glial implants in a child with gliomatosis peritonei

Glial peritoneal implants, commonly referred to as gliomatosis peritonei, are an occasional feature of ovarian teratomas. They are benign nodules of mature glial tissue and usually do not adversely affect outcome. We present the case of a 12-year-old girl who underwent excision of an immature ovarian teratoma, along with biopsies of multiple glial peritoneal implants. She also had a 2-cm right-sided pleural mass, which turned out to be normal glial tissue that was histologically indistinguishable from the peritoneal glial tissue. Pleural gliomatosis has not been described in the literature. The pathophysiology of gliomatosis peritonei was originally thought to be the direct extrusion or lymphatic spread of glial cells from the associated teratoma, although it has been postulated that the glial implants may instead be the result of pluripotent Mullerian stem cells that undergo metaplasia. This report provides evidence to bolster the metaplastic theory.

Intratibial Injection Causes Direct Pulmonary Seeding of Osteosarcoma Cells and Is Not a Spontaneous Model of Metastasis: A Mouse Osteosarcoma Model

Background Although metastasis is the major cause of mortality in patients with osteosarcoma, little is known about how micrometastases progress to gross metastatic disease. Clinically relevant animal models are necessary to facilitate development of new therapies to target indolent pulmonary metastases. Intratibial injection of human and murine osteosarcoma cell lines have been described as orthotopic models that develop spontaneous pulmonary metastasis over time. However, there is variability in reported injection techniques and metastatic efficiency. Questions/purposes We aimed to characterize a widely used murine model of metastatic osteosarcoma, determine whether it is appropriate to study spontaneous pulmonary metastasis by establishing a reliable volume for intratibial injection, determine the incidence of primary tumor and metastatic formation, determine the kinetics of pulmonary metastatic seeding and outgrowth, and the contribution of the primary tumor to subsequent development of metastasis. Methods The metastatic mouse osteosarcoma cell line K7M2 was injected into the tibia of mice. The maximum volume that could be injected without leakage was determined using Evan’s blue dye (n = 8 mice). Primary tumor formation and metastatic efficiency were determined by measuring the incidence of primary tumor and metastatic formation 4 weeks after intratibial injection (n = 30). The kinetics of metastatic development were determined by performing serial euthanasia at 1, 2, 3, and 4 weeks after injection (n = 24; five to six mice per group). Number of metastatic foci/histologic lung section and metastatic burden/lung section (average surface area of metastatic lesions divided by the total surface area of the lung) was calculated in a blinded fashion. To test the contribution of the primary tumor to subsequent metastases, amputations were performed 30 minutes, 4 hours, or 24 hours after injection (n = 21; five to six mice per group). Mice were euthanized after 4 weeks and metastatic burden calculated as described previously, comparing mice that had undergone amputation with control, nonamputated mice. Differences between groups were calculated using Kruskal-Wallis and one-way analysis of variance. Results The maximum volume of cell suspension that could be injected without leakage was 10 &mgr;L. Intratibial injection of tumor cells led to intramedullary tumor formation in 93% of mice by 4 weeks and resulted in detectable pulmonary metastases in 100% of these mice as early as 1 week post-injection. Metastatic burden increased over time (0.88% ± 0.58, week 1; 6.6% ± 5.3, week 2; 16.1% ± 12.5, week 3; and 40.3% ± 14.83, week 4) with a mean difference from week 1 to week 4 of -39.38 (p < 0.001; 95% confidence interval [CI], -57.39 to -21.37), showing pulmonary metastatic growth over time. In contrast, the mean number of metastatic foci did not increase from week 1 to week 4 (36.4 ± 33.6 versus 49.3 ± 26.3, p = 0.18). Amputation of the injected limb at 30 minutes, 4 hours, and 24 hours after injection did not affect pulmonary metastatic burden at 4 weeks, with amputation as early as 30 minutes post-injection resulting in a metastatic burden equivalent to tumor-bearing controls (48.9% ± 6.1% versus 40.9% ± 15.3%, mean difference 7.96, p = 0.819; 95% CI, -33.9 to 18.0). Conclusions There is immediate seeding of the metastatic site after intratibial injection of the K7M2 osteosarcoma cell line, independent of a primary tumor. This is therefore not a model of spontaneous metastasis. Clinical Relevance This model should not be used to study the early components of the metastatic cascade, but rather used as an experimental model of metastasis. Improved understanding of this commonly used model will allow for proper interpretation of existing data and inform the design of future studies exploring the biology of metastasis in osteosarcoma.