Hodgkin Lymphoma-related Vanishing Bile Duct Syndrome Cholestasis Resolved After Chemotherapy.

Vanishing bile duct syndrome is a rare paraneoplastic syndrome occasionally seen in pediatric Hodgkin lymphoma. It is usually regarded as a fatal disorder. Here, we present a case of vanishing bile duct syndrome cholestasis related to Hodgkin lymphoma that resolved after chemotherapy and radiation.

Ewing sarcoma in a child with neurofibromatosis type 1.

We report here on a case of Ewing sarcoma (ES) occurring in a child with neurofibromatosis type 1. The sarcoma had an EWSR1-ERG translocation as well as loss of the remaining wild-type allele of NF1. Loss of the NF1 wild-type allele in the tumor suggests that activation of the Ras pathway contributed to its evolution. Review of available public data suggests that secondary mutations in the Ras pathway are found in ∼3% of ESs. This case suggests that Ras pathway activation may play a role in tumor progression in a subset of ESs.

Congenital Cystic Lung Lesions: Evolution From In-utero Detection to Pathology Diagnosis-A Multidisciplinary Approach.

Congenital cystic lung lesions are a group of rare pathologies that are usually diagnosed in the prenatal period. The majority of these lesions are diagnosed at pathology examination as congenital pulmonary airway malformations (CPAM) and bronchopulmonary sequestration (BPS). These lesions are typically managed by surgical intervention within the first year of life and have an excellent prognosis. We examined the evolution of imaging appearances from prenatal diagnosis to postnatal work-up of these lesions and correlate imaging and pathological findings. An 8-year retrospective review of the perinatal and pathology database of a single tertiary care center identified 42 cases of congenital cystic lung lesions of which 36 had known prenatal ultrasound and prenatal course available. Final pathologic diagnoses were 15 CPAM (41%), 7 BPS (19%), and 9 hybrid BPS and CPAM lesions (25%). Five cases with bronchial atresia were also identified (either in isolation or associated with CPAM or BPS). The overall characteristics of these lesions by prenatal ultrasound, postnatal imaging, and ultimate histopathologic diagnosis are described.

Pathologic Characteristics, Natural History, and Prognostic Implications of BRAFV600E Mutation in Pediatric Papillary Thyroid Carcinoma.

The BRAFV600E mutation is the most common genetic aberration in papillary thyroid cancer (PTC), found in up to 68% of PTC in adults where it is associated with aggressive features. The incidence of this mutation in pediatric PTC is less frequent, reported as 0%-20% in the past and up to 63% in one recent series. Data suggest the mutation is not associated with an aggressive course in children; however, there are limited numbers of reported case series, so the prognostic implications remain poorly understood. The aim of this retrospective study was to examine the histologic characteristics and clinical outcomes of BRAF positive pediatric PTC at a single institution. A 12-year retrospective review of all thyroidectomies performed at a tertiary medical center identified 59 pediatric cases with a surgical pathology diagnosis of PTC. Fifty patients had BRAFV600E mutation analysis data and were selected for further study. BRAFV600E mutations were present in 48% of cases (n = 24) and absent in 52% (n = 26). The molecular characteristics of the BRAF negative cases will further be evaluated in future studies. BRAF positive cases occurred in patients who were on average older than the BRAF negative patients. Classic histology PTC was present in both BRAF positive and negative cases; however, only cases with classic PTC histology were positive for the mutation. No patients died and BRAF mutation was not associated with an increased recurrence rate. Our study supports BRAFV600E is more common in children than previously thought and does not portend a more aggressive clinical course.

A comparison of suction and full-thickness rectal biopsy in children.

BACKGROUND: Rectal biopsy evaluation by an experienced pathologist is the gold standard in diagnosis of Hirschsprung's disease (HD). Although both suction rectal biopsy (SRB) and full-thickness (FTRB) rectal biopsy are performed, the ability for SRB to obtain adequate tissue in older children has been questioned. We hypothesized that SRB and FTRB yield tissue specimens of different size but are equally adequate for diagnosis. METHODS: Records of children who underwent rectal biopsy to evaluate for HD between January 2007 and July 2014 were reviewed. Volume, percent submucosa, and specimen adequacy were compared between biopsy techniques, and the effect of age on biopsy adequacy was assessed. Data were analyzed by mixed-effects models with covariate adjustment for age at biopsy and Fisher's exact test. RESULTS: Forty-seven children underwent a total of 58 biopsies, 45 SRB and 13 FTRB. Thirty-seven were performed before 12 mo of age, and 21 after 12 mo of age. Volume of SRB specimens was significantly smaller than FTRB across ages (14.8 ± 7.8 mm(3)versus 121.3 ± 13.8 mm(3), P = 0.0001). Percent submucosa did not differ significantly between SRB and FTRB specimens across ages (63.8 ± 2.7% versus 66.5 ± 4.3%, P = 0.575). The number of inadequate biopsies was low and not significantly different across ages (P = 0.345), or when comparing by biopsy method (P = 0.689). All biopsies were clinically diagnostic. There were no complications. CONCLUSIONS: Tissue specimens obtained by SRB are smaller than those obtained by FTRB, especially in older children. SRB and FTRB appear equivalent in their ability to provide adequate submucosa. Differences in cost and patient satisfaction between rectal biopsy techniques must be studied to further define the best overall technique.

Prevalence and Clinical, Endoscopic, and Pathological Features of Duodenitis in Children.

OBJECTIVES: Although gastritis and esophagitis are well studied in children, there is very limited literature on duodenitis in children. We aimed to assess the prevalence, etiology, clinical, endoscopic, and pathological features in a large cohort of unselected children with duodenitis. METHODS: We reviewed the pathology reports of all the upper endoscopies performed at our institution during 5 years to identify children with duodenitis. Biopsy sections were reviewed to confirm the diagnosis of duodenitis. Demographic, clinical, endoscopic data, and the presence of associated gastritis and esophagitis were noted in all of the children with duodenitis. The etiology of duodenitis was correlated with the patients' clinical diagnosis. RESULTS: Out of 2772 children who had endoscopy, 352 had duodenitis with the prevalence rate of 12.7%. Gastritis was seen in 64% of children with duodenitis compared with 46% of children without duodenitis (P < 0.001). Common indications for endoscopy in children with duodenitis were abdominal pain, positive celiac serology, and diarrhea. The most common etiology was celiac disease (32%), followed by Crohn disease (13%), ulcerative colitis (3%), and Helicobacter pylori infection (6%). In 63% of cases, the endoscopic appearance of duodenum was normal. Cryptitis, villous changes, and cellular infiltration were noted on histology. CONCLUSIONS: Prevalence of duodenitis is 12.7% in children undergoing endoscopy. Celiac disease and inflammatory bowel disease are common causes of duodenitis. Associated gastritis is common in children with duodenitis, and the correlation of endoscopic appearance with histology is poor.

A hydrogel-endothelial cell implant mimics infantile hemangioma: modulation by survivin and the Hippo pathway.

Microvascular endothelial cells cultured in three-dimensional hydrogel scaffolds form a network of microvessel structures when implanted subcutaneously in mice, inosculate with host vessels, and over time remodel into large ectatic vascular structures resembling hemangiomas. When compared with infantile hemangiomas, similarities were noted, including a temporal progression from a morphological appearance of a proliferative phase to the appearance of an involuted phase, mimicking the proliferative and involutional phases of infantile hemangioma. Consistent with the progression of a proliferative phase to an involuted phase, both the murine implants and human biopsy tissue exhibit reduced expression of Ajuba, YAP, and Survivin labeling as they progressed over time. Significant numbers of CD45+, CD11b+, Mac3+ mononuclear cells were found at the 2-week time point in our implant model that correlated with the presence of CD45+, CD68+ mononuclear cells observed in biopsies of human proliferative-phase hemangiomas. At the 4-week time point in our implant model, only small numbers of CD45+ cells were detected, which again correlated with our findings of significantly diminished CD45+, CD68+ mononuclear cells in human involutional-phase hemangiomas. The demonstration of mononuclear cell infiltration transiently in the proliferative phase of these lesions suggests that the vascular proliferation and/or regression may be driven in part by an immune response. Gross and microscopic morphological appearances of human proliferative and involutional hemangiomas and our implant model correlate well with each other as do the expression levels of Hippo pathway components (Ajuba and YAP) and Survivin and correlate with proliferation in these entities. Inhibitors of Survivin and Ajuba (which we have demonstrated to inhibit proliferation and increase apoptosis in murine hemangioendothelioma cell tissue culture) may have potential as other beneficial treatments for proliferating infantile hemangiomas. This implant model may have potential as a modest through-put screen for testing and development of therapeutics targeted at the proliferative phase of infantile hemangiomas, reducing the subsequent postinvolutional scarring or deformities sometimes associated with these lesions.

Histopathology of duodenal mucosal lesions in pediatric patients with inflammatory bowel disease: statistical analysis to identify distinctive features.

Histopathologic lesions of the upper gastrointestinal tract (UGT) are common in inflammatory bowel disease (IBD) patients. Pediatric patients have a higher incidence of IBD-associated gastritis and duodenitis than do adults. This study aimed to identify histopathologic features of duodenal lesions in the pediatric population that are characteristic of IBD, compared to duodenal pathology of different etiopathogenesis. We performed a retrospective analysis of UGT biopsies from pediatric patients with a histopathologic diagnosis of duodenitis (0-18 years of age) over a 7-year period. We identified 40 cases of duodenitis associated with Crohn's disease (CD) and 10 cases associated with ulcerative colitis (UC) and compared the histopathologic characteristics of the duodenitis with age-matched controls consisting of 40 cases duodenitis associated with celiac disease and 40 non-Helicobacter pylori-associated (NOS) etiology duodenitis cases. The histologic features that were evaluated included presence of granulomas, duodenal cryptitis, erosion, lamina propria eosinophils, villous blunting, increased intraepithelial lymphocytes (IELs), and crypt hyperplasia, among others. Additionally, we evaluated the presence of associated gastritis in all of these groups. Statistical analysis to identify significant differences was performed using Kruskal-Wallis testing. Cryptitis was the most distinctive feature of IBD-associated duodenitis. Granulomas were exceptionally rare. The severity of villous blunting and presence of IELs was significantly different in the IBD versus the celiac group. There is a significant overlap with duodenal lesions of different etiopathogenesis, including villous blunting and eosinophilia. With the exclusion of granulomas, cryptitis seems the most distinctive feature of the duodenal lesions associated with IBD.