Acquired Esophageal Strictures in Children: Morphometric and Immunohistochemical Analyses

BACKGROUND

Esophageal strictures (ES) in children are not well characterized pathologically. We report unique histopathologic analyses of resected acquired ES and control esophagi (CE).

METHODS

Muscle layer thicknesses were measured in intact well-oriented areas; inflammatory cells were counted in the most inflamed high power field (hpf). Sections were stained with relevant antibodies. Results were expressed as median, lower and upper quartiles. Wilcoxon Rank Sums non-parametric test was used to compare groups; P ≤ 0.05 was considered significant.

RESULTS

All ES (N = 10) showed focal replacement of lamina propria, muscularis mucosa and submucosa by actin+ fibers emanating from muscularis propria. Compared to CE (N = 8), ES displayed significantly thickened muscularis mucosa and propria, and increased mast cells (tryptase- and chymase-positive), and eosinophils in muscle layers (all P ≤ 0.01). Matrix proteins periostin and fibronectin were identified in the muscle layers of CE, and in the extracellular matrix in areas of disrupted architecture in ES.

CONCLUSIONS

Compared to CE, acquired ES in children show significant structural alterations, including obliterative muscularization, inflammatory cell mural infiltrates, and extracellular matrix protein deposits. Therapies targeting connective tissue expansion, mast cells, eosinophils and inflammation may be beneficial to treat ES.

DICER1 Mutations and Differentiated Thyroid Carcinoma: Evidence of a Direct Association

CONTEXT

DICER1 germline mutation carriers have an increased predisposition to cancer, such as pleuropulmonary blastoma (PPB) and Sertoli-Leydig cell tumor (SLCT), and a high prevalence of multinodular goiter (MNG). Although differentiated thyroid carcinoma (DTC) has been reported in some DICER1 mutation carriers with PPB treated with chemotherapy, the association of DTC with DICER1 mutations is not well established.

CASE DESCRIPTION

We report a family with DICER1 mutation and familial DTC without a history of chemotherapy. A 12-year-old female (patient A) and her 14-year-old sister (patient B) presented with MNG. Family history was notable for a maternal history of DTC and bilateral ovarian SLCT. Both sisters underwent total thyroidectomy. Pathological examination showed nodular hyperplasia and focal papillary thyroid carcinoma within hyperplastic nodules. Subsequently, patient A developed virilization secondary to a unilateral ovarian SLCT. During her evaluation, an incidental cystic nephroma was also found. Three other siblings had MNG on surveillance ultrasound examination; two had thyroidectomies, and one had two microscopic foci of papillary carcinoma. Patient A, her mother, and four affected siblings had a germline heterozygous pathogenic DICER1 mutation c.5441C>T in exon 25, resulting in an amino acid change from p.Ser1814Leu of DICER1. Somatic DICER1 RNase IIIb missense mutations were identified in thyroid nodules from three of the four siblings.

CONCLUSIONS

This family provides novel insight into an emerging phenotype for DICER1 syndrome, with evidence that germline DICER1 mutations are associated with an increased risk of developing familial DTC, even in the absence of prior treatment with chemotherapy.

Myocardial infarction due to a retained epicardial pacing wire

A 20-year-old man with a temporary epicardial pacing wire retained after infant repair of an atrioventricular septal defect presented with cardiopulmonary arrest. After resuscitation with extracorporeal membranous oxygenation, a coronary angiogram demonstrated a retained epicardial pacing wire compressing the left anterior descending artery and obtuse marginals. Owing to poor prognostic findings on a computed tomography scan of his head, he was terminally withdrawn from mechanical support. This case demonstrates a potential devastating complication of a retained temporary epicardial pacing wire.

A Rare Case of Clear Cell Adenocarcinoma of the Bladder with Unique Pathological Features

Clear cell adenocarcinomas of the urinary bladder are rare tumors with an unknown histogenesis. Since these tumors appear histologically similar to clear cell tumors of the female genital tract, a mullerian histogenesis has been proposed. Several publications have examined the immunohistochemical properties of clear cell adenocarcinomas to improve understanding of the cause and pathogenesis of this tumor. While specific criteria for a diagnosis of clear cell adenocarcinoma have not been defined, there are consistent staining patterns suggested for characterization. We present an important case of clear cell adenocarcinoma of the bladder with a unique staining pattern. We review the literature and discuss the differential diagnosis and various theories concerning the origin of this rare tumor.