Central Venous Catheter Consideration in Pediatric Oncology: A Systematic Review and Meta-analysis From the American Pediatric Surgical Association Cancer Committee.

BACKGROUND: Tunneled central venous catheters (CVCs) are the cornerstone of modern oncologic practice. Establishing best practices for catheter management in children with cancer is essential to optimize care, but few guidelines exist to guide placement and management. OBJECTIVES: To address four questions: 1) Does catheter composition influence the incidence of complications; 2) Is there a platelet count below which catheter placement poses an increased risk of complications; 3) Is there an absolute neutrophil count (ANC) below which catheter placement poses an increased risk of complications; and 4) Are there best practices for the management of a central line associated bloodstream infection (CLABSI)? METHODS: Data Sources: English language articles in Ovid Medline, PubMed, Embase, Web of Science, and Cochrane Databases. STUDY SELECTION: Independently performed by 2 reviewers, disagreements resolved by a third reviewer. DATA EXTRACTION: Performed by 4 reviewers on forms designed by consensus, quality assessed by GRADE methodology. RESULTS: Data were extracted from 110 manuscripts. There was no significant difference in fracture rate, venous thrombosis, catheter occlusion or infection by catheter composition. Thrombocytopenia with minimum thresholds of 30,000-50,000 platelets/mcl was not associated with major hematoma. Limited evidence suggests a platelet count <30,000/mcL was associated with small increased risk of hematoma. While few studies found a significant increase in CLABSI in CVCs placed in neutropenic patients with ANC<500Kcells/dl, meta-analysis suggests a small increase in this population. Catheter removal remains recommended in complicated or persistent infections. Limited evidence supports antibiotic, ethanol, or hydrochloric lock therapy in definitive catheter salvage. No high-quality data were available to answer any of the proposed questions. CONCLUSIONS: Although over 15,000 tunneled catheters are placed annually in North America into children with cancer, there is a paucity of evidence to guide practice, suggesting multiple opportunities to improve care. LEVEL OF EVIDENCE: III. This study was registered as PROSPERO 2019 CRD42019124077.

Survival outcomes in pediatric patients with metastatic Ewing sarcoma who achieve a rapid complete response of pulmonary metastases.

PURPOSE: Our objectives were to compare overall survival (OS) and pulmonary relapse between patients with metastatic Ewing sarcoma (EWS) at diagnosis who achieve rapid complete response (RCR) and those with residual pulmonary nodules after induction chemotherapy (non-RCR). PATIENTS AND METHODS: This retrospective cohort study included children under 20 years with metastatic EWS treated from 2007 to 2020 at 19 institutions in the Pediatric Surgical Oncology Research Collaborative. Chi-square tests were conducted for differences among groups. Kaplan-Meier curves were generated for OS and pulmonary relapse. RESULTS: Among 148 patients with metastatic EWS at diagnosis, 61 (41.2%) achieved RCR. Five-year OS was 71.2% for patients who achieved RCR, and 50.2% for those without RCR (p = .04), and in multivariable regression among patients with isolated pulmonary metastases, RCR (hazards ratio [HR] 0.42; 95% confidence interval [CI]: 0.17-0.99) and whole lung irradiation (WLI) (HR 0.35; 95% CI: 0.16-0.77) were associated with improved survival. Pulmonary relapse occurred in 57 (37%) patients, including 18 (29%) in the RCR and 36 (41%) in the non-RCR groups (p = .14). Five-year pulmonary relapse rates did not significantly differ based on RCR (33.0%) versus non-RCR (47.0%, p = .13), or WLI (38.8%) versus no WLI (46.0%, p = .32). DISCUSSION: Patients with EWS who had isolated pulmonary metastases at diagnosis had improved OS if they achieved RCR and received WLI, despite having no significant differences in rates of pulmonary relapse.

Critical elements of pediatric neuroblastoma surgery.

Neuroblastoma (NB) is the most common solid extracranial malignancy of childhood with an incidence of 1 per 100,000 in the United States compromising approximately 10 % of childhood cancer. Unfortunately, patients with high-risk NG continue to have long-term survival less than 50 %. Both Children's Oncology Group and the International Society of Paediatric Oncology have demonstrated the important role of surgery in the treatment of high-risk NB. Herein, we compose the results of an extensive literature review as well as expert opinion from leaders in pediatric surgical oncology, to present the critical elements of effective surgery for high-risk neuroblastoma.

Development of a template for operative reporting of pediatric cancer surgery in limited-resource settings by using a modified Delphi method.

PURPOSE: A comprehensive operative report for cancer surgery is crucial for accurate disease staging, risk stratification, and therapy escalation/de-escalation, which affects the outcome. Narrative operative reports may fail to include some critical findings. Furthermore, standardized operative reports can form the basis of a local registry, which is often lacking in limited-resource settings (LRSs). In adult literature, synoptic operative reports (SOR) contain more key findings than narrative operative reports. In the LRSs, where the capacity of diagnostic pathology services is typically suboptimal, the value of a thorough operative report is even greater. The aim of this study was to develop a SOR template to help standardize childhood cancer surgery reporting in LRSs. METHODS: Twenty-three experts in pediatric cancer with extensive experience practicing in LRSs were invited to participate in a modified Delphi procedure. SOR domains for pediatric oncology surgery were drafted based on a literature search and then modified based on experts' opinions. The experts anonymously answered multiple rounds of online questionnaires until all domains and subdomains reached a consensus, which was predefined as 70% agreement. RESULTS: Sixteen experts participated in the study, and two rounds of the survey were completed. Twenty-one domains were considered relevant, including demographics, diagnosis, primary site, preoperative disease stage, previous tumor biopsy or surgery, preoperative tumor rupture, neoadjuvant therapy, surgical access, type of resection, completeness of resection, tumor margin assessment, locoregional tumor extension, organ resection, intraoperative tumor spillage, vascular involvement, lymph node sampling, estimated blood loss, intraoperative complications and interventions to address them, specimen names, and specimen orientation. CONCLUSION: We developed a SOR template for pediatric oncology surgery in LRSs. Consensus for all 21 domains and associated subdomains was achieved using a modified Delphi procedure.

Cervical Collar Clearance in Obtunded Children Presenting Without a Known Traumatic Mechanism: Is Imaging Necessary?

BACKGROUND: Obtunded pediatric patients are often placed in cervical collars (c-collars) to protect their cervical spine (c-spine) while injury is being ruled out, even without a known traumatic injury. The goal of this study was to determine the necessity of c-collars in this population by determining the rate of c-spine injury among patients with suspected non-traumatic mechanisms of loss of consciousness. METHODS: A single institution, ten-year retrospective chart review was conducted including all obtunded patients admitted to the Pediatric Intensive Care Unit without a known traumatic event. Patients were categorized into five groups based on etiology of obtundation: respiratory, cardiac, medical/metabolic, neurologic, and other. Comparisons were made between those placed in a c-collar and a control group who were not, using Wilcoxon rank sum test for continuous measures, and Chi-square or Fisher's exact test for categorical measures. RESULTS: 464 patients were included, of which 39 (8.41%) were placed in a c-collar. There was a significant difference in whether a patient was placed in a c-collar based on diagnosis category (p < 0.001). Those placed in a-c-collar were more likely to undergo imaging studies than the control group (p < 0.001). The overall incidence of c-spine injury in this patient population in our study was zero. CONCLUSION: Cervical collar placement and radiographic evaluation is not necessary in obtunded pediatric patients who present without a known traumatic mechanism as the overall risk of injury is low. Consideration for collar placement should be given in cases when trauma cannot be definitively ruled out at initial evaluation. LEVELS OF EVIDENCE: III.

IGF2BP1 regulates the cargo of extracellular vesicles and promotes neuroblastoma metastasis.

Neuroblastoma is a highly metastatic cancer, and thus is one of the leading causes of cancer-related mortalities in pediatric patients. More than 50% of NB cases exhibit 17q21-ter partial chromosomal gain, which is independently associated with poor survival, suggesting the clinical importance of genes at this locus in NB. IGF2BP1 is one such proto-oncogene located at 17q locus, and was found to be upregulated in patients with metastatic NBs. Here, utilizing multiple immunocompetent mouse models, along with our newly developed highly metastatic NB cell line, we demonstrate the role of IGF2BP1 in promoting NB metastasis. Importantly, we show the significance of small extracellular vesicles (EVs) in NB progression, and determine the pro-metastatic function of IGF2BP1 by regulating the NB-EV-protein cargo. Through unbiased proteomic analysis of EVs, we discovered two novel targets (SEMA3A and SHMT2) of IGF2BP1, and reveal the mechanism of IGF2BP1 in NB metastasis. We demonstrate that IGF2BP1 directly binds and governs the expression of SEMA3A/SHMT2 in NB cells, thereby modulating their protein levels in NB-EVs. IGF2BP1-affected levels of SEMA3A and SHMT2 in the EVs, regulate the formation of pro-metastatic microenvironment at potential metastatic organs. Finally, higher levels of SEMA3A/SHMT2 proteins in the EVs derived from NB-PDX models indicate the clinical significance of the two proteins and IGF2BP1-SEMA3A/SHMT2 axis in NB metastasis.

Cell Adhesion Molecules in Neuroblastoma: Complex Roles, Therapeutic Potential.

Neuroblastoma, a biologically heterogeneous tumor derived from neural crest cells, accounts for approximately 15% of childhood deaths from cancer. Recently, scientific literature has explored the role of cell adhesion molecules (CAMs) in cancer metastasis through cell detachment, migration, and invasion. Through a review of the current literature, it is evident that expression of different CAMs on neuroblastoma tumors is associated with favorable or unfavorable clinical prognosis. In patients diagnosed with neuroblastoma, treatment strategies include chemotherapy, surgery, radiotherapy, stem cell transplant, and more recently, immunotherapy and other targeted therapies. Long term survival remains poor despite multimodality treatment, especially for children with high-risk neuroblastoma, making it more necessary to explore innovative targeted therapies. CAMs have immense potential as therapeutic targets, but there is a need for growth and scientific exploration before CAM therapies become clinically useful.

Thoracic Neuroblastoma: A Novel Surgical Model for the Study of Extra-adrenal Neuroblastoma.

BACKGROUND/AIM: Neuroblastoma is clinically and molecularly heterogeneous, with poor outcomes despite multimodal treatment strategies. The primary tumor site is an independent predictor of survival; adrenal tumors have the worst outcomes, while posterior mediastinum tumors carry a more favorable prognosis. MATERIALS AND METHODS: To elucidate the role of the primary tumor microenvironment in mediating survival outcomes, we developed a mouse model for the study of extra-adrenal neuroblastoma by injecting luciferase-tagged cells into either the subpleural space of the posterior chest or the adrenal gland. RESULTS: Solid tumors developed in the thoracic cavity at the same rate and efficiency as the adrenal as early as one week post-surgery. The survival rate following surgery was equivalent, though the physiological tolerance for large tumors was lower in the thoracic group. CONCLUSION: This novel mouse model of survivable extra-adrenal neuroblastoma will enable future investigations of the distinct tumor microenvironments between the adrenal gland and posterior mediastinum.

Pediatric solid tumors and associated cancer predisposition syndromes: Workup, management, and surveillance. A summary from the APSA Cancer Committee.

BACKGROUND/PURPOSE: Cancer predisposition syndromes (CPS) are a heterogeneous group of inherited disorders that greatly increase the risk of developing malignancies. CPS are particularly relevant to pediatric surgeons since nearly 10% of cancer diagnoses are due to inherited genetic traits, and CPS often contribute to cancer development during childhood. MATERIALS/METHODS: The English language literature was searched for manuscripts, practice guidelines, and society statements on "cancer predisposition syndromes in children". Following review of these manuscripts and cross-referencing of their bibliographies, tables were created to summarize findings of the most common CPS associated with surgically treated pediatric solid malignancies. RESULTS: Pediatric surgeons should be aware of CPS as the identification of one of these syndromes can completely change the management of certain tumors, such as WT. The most common CPS associated with pediatric solid malignancies are outlined, with an emphasis on those most often encountered by pediatric surgeons: neuroblastoma, Wilms' tumor, hepatoblastoma, and medullary thyroid cancer. Frequently associated non-tumor manifestations of these CPS are also included as a guide to increase surgeon awareness. Screening and management guidelines are outlined, and published genetic testing and counseling guidelines are included where available. CONCLUSION: Pediatric surgeons play an important role as surgical oncologists and are often the first point of contact for children with solid tumors. In their role of delivering a diagnosis and developing a follow-up and treatment plan as part of a multidisciplinary team, familiarity with common CPS will ensure evidence-based practices are followed, including important principles such as organ preservation and intensified surveillance plans. This review defines and summarizes the CPS associated with common childhood solid tumors encountered by the pediatric surgeon, as well as common non-cancerous disease stigmata that may help guide diagnosis. TYPE OF STUDY: Summary paper. LEVEL OF EVIDENCE: 5.

Update on pediatric testicular germ cell tumors.

BACKGROUND: Testicular germ cell tumors are uncommon tumors that are encountered by pediatric surgeons and urologists and require a knowledge of appropriate contemporary evaluation and surgical and medical management. METHOD: A review of the recommended diagnostic evaluation and current surgical and medical management of children and adolescents with testicular germ cell tumors based upon recently completed clinical trials was performed and summarized in this article. RESULTS: In this summary of childhood and adolescent testicular germ cell tumors, we review the initial clinical evaluation, surgical and medical management, risk stratification, results from recent prospective cooperative group studies, and clinical outcomes. A summary of recently completed clinical trials by pediatric oncology cooperative groups is provided, and best surgical practices are discussed. CONCLUSIONS: Testicular germ cell tumors in children are rare tumors. International collaborations, data-sharing, and enrollment of patients at all stages and risk classifications into active clinical trials will enhance our knowledge of these rare tumors and most importantly improve outcomes of patients with testicular germ cell tumors. LEVEL OF EVIDENCE: This is a review article of previously published and referenced level 1 and 2 studies, but also includes expert opinion level 5, represented by the American Pediatric Surgical Association Cancer Committee.

Surgical management in pediatric neuroblastoma diagnosis and treatment: a 20-year, single-center experience.

BACKGROUND: The currently utilized International Neuroblastoma Risk Group (INRG) staging system developed in 2009 uses image-defined risk factors as a measure of surgical risk, separating resectable neuroblastoma from those best preceded by chemotherapy. The previous International Neuroblastoma Staging System was based primarily on surgical findings. We hypothesized there would be a change to the role of the surgeon in neuroblastoma treatment in the more recent decade. METHODS: This is a single center 20-year retrospective analysis of 104 patients with International Classification of Diseases-9 and -10 codes for neuroblastoma. Patient demographics, tumor site, cancer treatment modality, survival, biopsy technique, surgical intervention, and pathology staging were collected. Data was analyzed by analysis of variance (ANOVA) and Student's t test. RESULTS: There was a decrease in open surgeries for extra-adrenal neuroblastomas in the later decade (77%, 31%, P = 0.01). There was a narrowing of the time interval to surgery in the later cohort, likely as a result of uniformity in surgical timing on treatment protocols relying on INRG staging. CONCLUSIONS: Our findings mirror changes in practice patterns globally. We found an increase in minimally invasive approaches but did not find a difference in the role of the surgeon under the INRG staging system.

Lymphatic malformations: a 20-year single institution experience.

PURPOSE: Lymphatic malformations (LMs) are congenital abnormalities which result from disturbances in the embryologic development of the lymphatic system. We sought to determine the characteristics and treatment patterns for LMs in a rural setting, and the effect of a specialized vascular malformations clinic on triage and follow-up. METHODS: This is a retrospective cohort study at a single tertiary care institution. Sixty-two patients were identified; chart review was completed to obtain demographic, surgery/sclerotherapy session and follow-up information. RESULTS: The head/neck region was the most predominant LM location (N = 26, 41.9%), followed by trunk (N = 16, 25.8%), extremity (N = 11, 17.7%), and intraabdominal/retroperitoneal (N = 7, 11.3%). Twenty-eight patients were managed non-surgically, while 21, 7 and 6 patients required surgery, sclerotherapy, or both. Head/neck LMs were the most likely to recur (73%, p = 0.028). Patients seen in specialty clinic had similar duration of follow-up and time to intervention, but were more often below 1 year of age (p = 0.030). Average LM volume among patients with available imaging was much larger in those referred to specialty clinic (73.2 cm3 versus 14.8 cm3, p = 0.022). CONCLUSION: Our experience reiterates not only the wide variety of clinical presentations of lymphatic malformations, but also demonstrates the necessity of multiple subspecialties and their collaboration to achieve prompt and efficacious treatment.

Lymphadenopathy in children: A streamlined approach for the surgeon - A report from the APSA Cancer Committee.

BACKGROUND/PURPOSE: Lymphadenopathy is a common complaint in children. Pediatric surgeons are often called upon to evaluate, treat, and/or biopsy enlarged lymph nodes. With many nonsurgical causes in the differential diagnosis, the surgeon plays the important role of providing reassurance and timely diagnosis while minimizing the pain and morbidity associated with surgical interventions in children. The purpose of this summary paper is to provide a management guide for surgeons working up children with lymphadenopathy. MATERIALS/METHODS: The English language literature was searched for "lymphadenopathy in children". All manuscript types were considered for review, regardless of medical specialty, with emphasis placed on published guidelines, algorithms, and reviews. After thorough review of these manuscripts and cross-referencing of their bibliographies, the attached algorithm was developed, with emphasis on the role and timing of surgical intervention. RESULTS: The APSA Cancer Committee developed the attached algorithm to fill a gap in the surgical literature. It outlines lymphadenopathy workup and treatment with emphasis on the role and timing of surgical intervention. CONCLUSION: This review defines and summarizes the common etiologies and presentations of lymphadenopathy in children, and offers a straightforward algorithm for evaluation of and treatment with an emphasis on malignancy risk and surgical management. TYPE OF STUDY: Summary paper. LEVEL OF EVIDENCE: Level V.

Computational Identification of Gene Networks as a Biomarker of Neuroblastoma Risk.

Neuroblastoma is a common cancer in children, affected by a number of genes that interact with each other through intricate but coordinated networks. Traditional approaches can only reconstruct a single regulatory network that is topologically not informative enough to explain the complexity of neuroblastoma risk. We implemented and modified an advanced model for recovering informative, omnidirectional, dynamic, and personalized networks (idopNetworks) from static gene expression data for neuroblastoma risk. We analyzed 3439 immune genes of neuroblastoma for 217 high-risk patients and 30 low-risk patients by which to reconstruct large patient-specific idopNetworks. By converting these networks into risk-specific representations, we found that the shift in patients from a low to high risk or from a high to low risk might be due to the reciprocal change of hub regulators. By altering the directions of regulation exerted by these hubs, it may be possible to reduce a high risk to a low risk. Results from a holistic, systems-oriented paradigm through idopNetworks can potentially enable oncologists to experimentally identify the biomarkers of neuroblastoma and other cancers.

Expression Patterns of Immune Genes Reveal Heterogeneous Subtypes of High-Risk Neuroblastoma.

High risk neuroblastoma (HR-NB) remains difficult to treat, and its overall survival (OS) is still below 50%. Although HR-NB is a heterogeneous disease, HR-NB patients are currently treated in a similar fashion. Through unsupervised biclustering, we further stratified HR-NB patients into two reproducible and clinically distinct subtypes, including an ultra-high risk neuroblastoma (UHR-NB) and high risk neuroblastoma (HR-NB). The UHR-NB subtype consistently had the worst OS in multiple independent cohorts ( P < 0 . 008 ). Out of 283 neuroblastoma-specific immune genes that were used for stratification, 39 of them were differentiated in UHR-NB, including four upregulated and 35 downregulated, as compared to HR-NB. The four UHR-NB upregulated genes (ADAM22, GAL, KLHL13 and TWIST1) were all upregulated in MYCN amplified neuroblastoma in 5 additional cohorts. TWIST1 and ADAM22 were also positively correlated with cancer stage, while GAL was an independent OS predictor in addition to MYCN and age. Furthermore, we identified 26 commonly upregulated and 311 downregulated genes in UHR-NB from all 4723 immune-related genes. While 43 KEGG pathways with molecular functions were enriched in the downregulated immune-related genes, only the P53 signaling pathway was enriched in the upregulated ones, which suggested that UHR-NB was a TP53 related subtype with reduced immune activities.

Minimally invasive surgery for abdominal and thoracic neuroblastic tumors: A systematic review by the APSA Cancer committee.

BACKGROUND: Minimally invasive surgery has broad applicability to pediatric diseases, including pediatric cancer resection. Neuroblastic tumors of childhood are highly variable in presentation, and so careful selection of appropriate candidates for minimally invasive resection is paramount to achieving safe and durable surgical and oncological outcomes. METHODS: The American Pediatric Surgical Association Cancer Committee developed questions seeking to better define the role of minimally invasive surgery for neuroblastic tumors. A search using PubMed, Medline, Embase, Web of Science, ProQuest Dissertations, and Clinical Trials was performed for articles published from 1998 to 2018 in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) guidelines. RESULTS: The evidence identified is all retrospective in nature. Minimally invasive surgical resection of neuroblastic tumors is safe for carefully selected smaller (4-6 cm) image defined risk factor (IDRF)-negative abdominal tumors when oncologic principles are followed. Size is a less-well defined criterion for thoracic neuroblastic tumors. Open approaches for both abdominal and thoracic tumors may be preferable in the presence of IDRF's. CONCLUSION: Small tumors without IDRF's are reasonable candidates for minimally invasive resection. Surgical oncologic guidelines should be closely followed. The quality of data supporting this systematic review is poor and highlights the need for refinement in the study of such surgical techniques to improve knowledge and outcomes for patients with neuroblastic tumors. TYPE OF STUDY: Systematic Review. LEVEL OF EVIDENCE: Level III and Level IV.

Retroperitoneal exploration with Vicryl mesh and fibrin tissue sealant for refractory chylous ascites.

BACKGROUND: Congenital chylous ascites poses a significant challenge in neonatal care, and often results in prolonged, complex hospital stays and increased mortality. Few effective options exist in refractory cases. METHODS: Patients aged 0 to 12 months with refractory chylous ascites underwent retroperitoneal exploration after medical treatment and minimally invasive therapies were unsuccessful. The retroperitoneum was completely exposed via left and right medial visceral rotation and opening the lesser sac. Visible leaks were ligated, and alternating layers of fibrin glue and Vicryl mesh were used to cover the entire retroperitoneum. RESULTS: All 4 patients had resolution of their chylous ascites. None required reoperation or reintervention for chyle leaks. All achieved goal enteral feeds at a median of 29 days postoperatively and were discharged from hospital at a median of 42 days postoperatively. CONCLUSIONS: Management of chylous ascites is extremely challenging in refractory cases. Complete retroperitoneal exposure with fibrin glue and Vicryl mesh application offers a definitive, reliable therapy for achieving cessation of lymphatic leakage and ultimate recovery for patients who fail all nonoperative approaches. STUDY TYPE: Therapeutic. LEVEL OF EVIDENCE: IV.

MIBG in neuroblastoma diagnosis and treatment.

Neuroblastoma is a heterogenous disease, with solid tumors arising in the adrenal gland or paraspinal regions in young children. Neuroblastoma is unique, with varied presentation and prognosis based on primary location and tumor stage. Tumor behavior and response to treatment ranges from spontaneous regression to disseminated, lethal disease depending on the individual biology of a patient's tumor. Stratification of the disease has changed, with patients now placed in low, intermediate, and high-risk categories depending on age, stage, and tumor biology. Long-term survival for the high-risk subset of patients with metastatic disease is <40% despite aggressive multimodal therapy. Derived from sympathoadrenal cells of the adrenal medulla and sympathetic nervous system, both malignant neuroblastoma and differentiated tumors have specialized norepinephrine transporter (NET) receptors which are naturally occurring in the sympathetic nervous system throughout the body. Metaiodobenzylguanidine (MIBG) is a norepinephrine analog that undergoes active uptake by NET receptors resulting in accumulation in neuroblastoma as well as tissues normally expressing the NET receptor. When radioiodine labeled, MIBG can be used for both diagnosis and treatment. This article describes the history of MIBG use in neuroblastoma, including its utility as an imaging modality for diagnosis as well as the varied ways in which is it included in the multimodal treatment algorithm.

Prolonged Absence of Mechanoluminal Stimulation in Human Intestine Alters the Transcriptome and Intestinal Stem Cell Niche.

BACKGROUND & AIMS: For patients with short-bowel syndrome, intestinal adaptation is required to achieve enteral independence. Although adaptation has been studied extensively in animal models, little is known about this process in human intestine. We hypothesized that analysis of matched specimens with and without luminal flow could identify new potential therapeutic pathways. METHODS: Fifteen paired human ileum samples were collected from children aged 2-20 months during ileostomy-reversal surgery after short-segment intestinal resection and diversion. The segment exposed to enteral feeding was denoted as fed, and the diverted segment was labeled as unfed. Morphometrics and cell differentiation were compared histologically. RNA Sequencing and Gene Ontology Enrichment Analysis identified over-represented and under-represented pathways. Immunofluorescence staining and Western blot evaluated proteins of interest. Paired data were compared with 1-tailed Wilcoxon rank-sum tests with a P value less than .05 considered significant. RESULTS: Unfed ileum contained shorter villi, shallower crypts, and fewer Paneth cells. Genes up-regulated by the absence of mechanoluminal stimulation were involved in digestion, metabolism, and transport. Messenger RNA expression of LGR5 was significantly higher in unfed intestine, accompanied by increased levels of phosphorylated signal transducer and activator of transcription 3 protein, and CCND1 and C-MYC messenger RNA. However, decreased proliferation and fewer LGR5+, OLFM4+, and SOX9+ intestinal stem cells (ISCs) were observed in unfed ileum. CONCLUSIONS: Even with sufficient systemic caloric intake, human ileum responds to the chronic absence of mechanoluminal stimulation by up-regulating brush-border enzymes, transporters, structural genes, and ISC genes LGR5 and ASCL2. These data suggest that unfed intestine is primed to replenish the ISC population upon re-introduction of enteral feeding. Therefore, the elucidation of pathways involved in these processes may provide therapeutic targets for patients with intestinal failure. RNA sequencing data are available at Gene Expression Omnibus series GSE82147.

Doxycycline Sclerotherapy Is Superior in the Treatment of Pediatric Lymphatic Malformations.

PURPOSE: To evaluate efficacy of sclerotherapy with doxycycline versus sodium tetradecyl sulfate (STS) for treatment of macrocystic and mixed lymphatic malformations (LMs). MATERIALS AND METHODS: This single-center retrospective review identified 41 children (17 boys; 24 girls; age range, 1 month to 15.4 y) who underwent sclerotherapy with doxycycline (n = 32) or STS (n = 9) for macrocystic (n = 31) or mixed (n = 10) LMs. There were 114 treatments performed, averaging 2.8 treatments (range, 1-8 treatments) per patient. Average follow-up time was 10 months (range, 1-59 months). Clinical response was deemed excellent or moderate if > 90% or > 50% of LMs resolved based on visual estimate. RESULTS: With doxycycline, 87% of patients (28 of 32) had excellent or moderate response with an average of 2.8 treatments (range, 1-7 treatments); 13% required subsequent resection. With 3% STS monotherapy, only 55% of patients (5 of 9) had excellent or moderate response with an average of 2.8 treatments (range, 1-8 treatments), and 33% required subsequent resection. Significantly fewer patients treated with STS responded well compared with patients treated with doxycycline (P = .03). Patients treated with STS had significantly longer follow-up than patients treated with doxycycline (27 months vs 6 months, P = .0001). CONCLUSIONS: Doxycycline monotherapy resulted in a high rate of excellent clinical outcomes after a few treatments without increased need for subsequent operative resection. These results support use of doxycycline sclerotherapy as primary treatment for macrocystic and mixed LMs in children.