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Dive into the research topics where Amer Heider is active.

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Featured researches published by Amer Heider.


The American Journal of Surgical Pathology | 2014

Tuberous sclerosis-associated renal cell carcinoma: a clinicopathologic study of 57 separate carcinomas in 18 patients.

Juan Guo; Maria Tretiakova; Megan L. Troxell; Adeboye O. Osunkoya; Oluwole Fadare; Ankur R. Sangoi; Steven S. Shen; Antonio Lopez-Beltran; Rohit Mehra; Amer Heider; John P. Higgins; Lara R. Harik; Xavier Leroy; Anthony J. Gill; Kiril Trpkov; Steven C. Campbell; Christopher G. Przybycin; Cristina Magi-Galluzzi; Jesse K. McKenney

Tuberous sclerosis complex (TSC) is an autosomal dominant disorder with characteristic tumors involving multiple organ systems. Whereas renal angiomyolipoma (AML) is common in TSC, renal cell carcinoma (RCC) is rarely reported. Fifty-seven RCCs from 13 female and 5 male TSC patients were reviewed. Age at surgery ranged from 7 to 65 years (mean: 42 y). Nine patients (50%) had multiple synchronous and/or metachronous RCCs (range of 2 to 20 RCCs) and 5 had bilateral RCCs (28%). Seventeen patients (94%) had histologically confirmed concurrent renal AMLs, including 15 with multiple AMLs (88%) and 9 (50%) with AMLs with epithelial cysts. None of the 15 patients with available clinical follow-up information had evidence of distant metastatic disease from 6 to 198 months after their initial surgery (mean: 52 mo). The 57 RCCs exhibited 3 major distinct morphologies: (1) 17 RCCs (30%) had features similar to tumors previously described as “renal angiomyoadenomatous tumor” or “RCC with smooth muscle stroma”; (2) 34 RCCs (59%) showed features similar to chromophobe RCC; and (3) 6 RCCs (11%) showed a granular eosinophilic-macrocystic morphology. Distinct histologic changes were also commonly present in the background kidney parenchyma and included cysts or renal tubules lined by epithelial cells with prominent eosinophilic cytoplasm, nucleomegaly, and nucleoli. Immunohistochemically, all RCCs tested showed strong nuclear reactivity for PAX8 and HMB45 negativity. Compared with sporadic RCCs, TSC-associated RCCs have unique clinicopathologic features including female predominance, younger age at diagnosis, multiplicity, association with AMLs, 3 recurring histologic patterns, and an indolent clinical course. Awareness of the morphologic and clinicopathologic spectrum of RCC in this setting will allow surgical pathologists to better recognize clinically unsuspected TSC patients.


Pediatric Radiology | 2016

Ultrasound-guided fine-needle aspiration biopsy of pediatric thyroid nodules

Pranav Moudgil; Ranjith Vellody; Amer Heider; Ethan A. Smith; Jason J. Grove; Marcus D. Jarboe; Steven W. Bruch; Jonathan R. Dillman

BackgroundThe role of US-guided fine-needle aspiration biopsy (US-FNAB) of thyroid nodules is not well-established in children.ObjectiveTo retrospectively assess the utility of US-FNAB of pediatric thyroid nodules.Materials and methodsWe reviewed Department of Radiology records to identify children who underwent US-FNAB of the thyroid between 2005 and 2013. Two board-certified pediatric radiologists reviewed pre-procedural thyroid US exams and documented findings by consensus. We recorded cytopathology findings and compared them to surgical pathology diagnoses if the nodule was resected. We also recorded demographic information, use of sedation or general anesthesia, and presence of on-site cytopathological feedback. The Student’s t-test was used to compare continuous data; the Fisher exact test was used to compare proportions.ResultsUS-FNAB was conducted on a total of 86 thyroid nodules in 70 children; 56 were girls (80%). Seventy-eight of the 86 (90.7%) US-FNAB procedures were diagnostic; 69/78 (88.5%) diagnostic specimens were benign (including six indeterminate follicular lesions that were proved at surgery to be benign) and 9/78 (11.5%) were malignant/suspicious for malignancy (all proved to be papillary carcinomas). There was no difference in size of benign vs. malignant lesions (P = 0.82) or diagnostic vs. non-diagnostic lesions (P = 0.87). Gender (P = 0.19), use of sedation/general anesthesia (P = 0.99), and presence of onsite cytopathological feedback (P = 0.99) did not affect diagnostic adequacy. Microcalcifications (P < 0.0001; odds ratio [OR] = 113.7) and coarse calcifications (P = 0.03; OR = 19.4) were associated with malignancy. Diagnoses at cytopathology and surgical pathology were concordant in 27/29 (93.1%) nodules; no US-FNAB procedure yielded false-positive or false-negative results for malignancy.ConclusionUS-FNAB of pediatric thyroid nodules is feasible, allows diagnostic cytopathological evaluation, and correlates with surgical pathology results in resected nodules.


Canadian Journal of Cardiology | 2014

Acute Necrotizing Eosinophilic Myocarditis in a Patient Taking Garcinia Cambogia Extract Successfully Treated With High-Dose Corticosteroids

Scott F. Allen; Robert W. Godley; Joshua Evron; Amer Heider; John M. Nicklas; Michael P. Thomas

A previously healthy 48-year-old woman was evaluated for lightheadedness and chest heaviness 2 weeks after starting the herbal supplement Garcinia cambogia. She was found to be hypotensive and had an elevated serum troponin level. The patient had a progressive clinical decline, ultimately experiencing fulminant heart failure and sustained ventricular arrhythmias, which required extracorporeal membrane oxygenation support. Endomyocardial biopsy results were consistent with acute necrotizing eosinophilic myocarditis (ANEM). High-dose corticosteroids were initiated promptly and her condition rapidly improved, with almost complete cardiac recovery 1 week later. In conclusion, we have described a case of ANEM associated with the use of Garcinia cambogia extract.


Radiology | 2017

Association between Testicular Microlithiasis and Testicular Neoplasia: Large Multicenter Study in a Pediatric Population

Andrew T. Trout; Jeanne S. Chow; Erin R. McNamara; Kassa Darge; Raul Ramirez Grueso; Marthe Munden; Sarah M. Rothan; Oscar M. Navarro; Marta Tijerin Bueno; Kevin E. Bove; Kudakwashe R. Chikwava; Amer Heider; M. John Hicks; Gino R. Somers; Bin Zhang; Jonathan R. Dillman

Purpose To retrospectively define the strength of association between testicular microlithiasis and testicular neoplasia in a large geographically diverse pediatric population. Materials and Methods Retrospective review of scrotal ultrasonographic (US) examination reports and pathology specimens obtained between January 2000 and May 2014 at six academic pediatric hospitals in North America was performed. Reported cases were reviewed to confirm microlithiasis. Radiology and pathology data bases were searched for pathology-proven testicular tumors (benign or malignant germ cell or stromal tumors). Association strength (risk) was expressed in terms of odds ratios (ORs) with and without adjustment for fixed study site effects based on logistic regression. Results A total of 37 863 individuals underwent scrotal US during the study period. Mean age was 11.1 years ± 4.7 [standard deviation] in boys with microlithiasis and 9.1 years ± 5.9 in boys without microlithiasis (P < .001). Microlithiasis was confirmed in 2.90% of patients (1097 of 37 863; range, 1.61%-5.25% across sites). It was unilateral in 21.97% (241 of 1097) of patients and bilateral in 78.0% (856 of 1097). Tumor was identified in 4.64% (51 of 1097) of boys with microlithiasis and 0.33% (122 of 36 766) of boys without (unadjusted OR, 14.65; 95% confidence interval [CI]: 10.29, 20.84; adjusted OR, 14.19). Malignant germ cell tumors were identified in 2.8% (31 of 1097) of boys with microlithiasis and 0.12% (45 of 36 766) of boys without microlithiasis (unadjusted OR, 17.26; 95% CI: 11.8, 25.25; adjusted OR, 22.37). Sex cord-stromal tumors were identified in 0.46% (five of 1097) of boys with microlithiasis and 0.079% (29 of 36 766) of boys without (unadjusted OR, 5.8; 95% CI: 2.1, 16; adjusted OR, 6.39). Conclusion There is a strong association between testicular microlithiasis and primary testicular neoplasia in this pediatric population.


Applied Immunohistochemistry & Molecular Morphology | 2016

Comprehensive Immunophenotypic Characterization of Adult and Fetal Testes, the Excretory Duct System, and Testicular and Epididymal Appendages.

Martin J. Magers; Aaron M. Udager; Arul M. Chinnaiyan; Diana French; Jeffrey L. Myers; Jeffrey M. Jentzen; Jonathan B. McHugh; Amer Heider; Rohit Mehra

The immunophenotype of a normal testis and the excretory duct system has not been studied comprehensively in fetal and adult patients without testicular disease or hormonal manipulation so far. In addition, testicular (TA) and epididymal (EA) appendages are frequent paratesticular structures without previously reported comprehensive immunophenotypic studies. Immunohistochemistry for multiple markers, including the androgen receptor (AR), the estrogen receptor (ER), the progesterone receptor (PR), the prostate-specific antigen, the prostate-specific membrane antigen, PAX8, WT1, calretinin, CK7, CK20, OCT4, SALL4, and CD117, was performed on full sections of testicular/paratesticular tissue from a large cohort of adult and fetal autopsy patients. In contrast to adult germ cells (GC), fetal GC strongly express OCT4 and CD117, although the expression of these proteins is lost in the early postnatal period; SALL4, in contrast, is expressed in both fetal and adult GC, with only weak and focal expression in adult patients. Fetal Sertoli cells (SC) express WT1 and calretinin strongly and diffusely, in contrast to adult SC. Both fetal and adult excretory duct systems express CK7 and PAX8 with frequent AR coexpression, and all 3 main segments of the excretory duct system (ductuli efferentes, epididymis, and vas deferens) have unique immunophenotypes. The rete testis also has a unique immunohistochemical expression pattern, which includes strong expression of CK7, PAX8, WT1, calretinin, and AR. Finally, of the adult autopsy patients examined, 80% had a TA, and 60% had an EA; these paratesticular structures occurred at stereotypical locations, demonstrated reproducible morphologic features, and had a unique immunophenotype relative to other studied structures, with strong CK7, PAX8, WT1, AR, ER, and PR coexpression. The testis and the paratestis may be involved by diverse neoplastic and non-neoplastic processes, and knowledge of the immunophenotypic expression spectrum of these tissues may aid in clinical diagnosis and advance our understanding of the pathogenesis of both oncologic and nononcologic disease processes.


Human Mutation | 2018

Compound heterozygosity for loss-of-function FARSB variants in a patient with classic features of recessive aminoacyl-tRNA synthetase-related disease

Anthony Antonellis; Stephanie N. Oprescu; Laurie B. Griffin; Amer Heider; Andrea Amalfitano; Jeffrey W. Innis

Aminoacyl‐tRNA synthetases (ARSs) are ubiquitously expressed enzymes that ligate amino acids onto tRNA molecules. Genes encoding ARSs have been implicated in phenotypically diverse dominant and recessive human diseases. The charging of tRNAPHE with phenylalanine is performed by a tetrameric enzyme that contains two alpha (FARSA) and two beta (FARSB) subunits. To date, mutations in the genes encoding these subunits (FARSA and FARSB) have not been implicated in any human disease. Here, we describe a patient with a severe, lethal, multisystem, developmental phenotype who was compound heterozygous for FARSB variants: p.Thr256Met and p.His496Lysfs*14. Expression studies using fibroblasts isolated from the proband revealed a severe depletion of both FARSB and FARSA protein levels. These data indicate that the FARSB variants destabilize total phenylalanyl‐tRNA synthetase levels, thus causing a loss‐of‐function effect. Importantly, our patient shows strong phenotypic overlap with patients that have recessive diseases associated with other ARS loci; these observations strongly support the pathogenicity of the identified FARSB variants and are consistent with the essential function of phenylalanyl‐tRNA synthetase in human cells. In sum, our clinical, genetic, and functional analyses revealed the first FARSB variants associated with a human disease phenotype and expand the locus heterogeneity of ARS‐related human disease.


Pediatric Blood & Cancer | 2017

Review at a multidisciplinary tumor board impacts critical management decisions of pediatric patients with cancer.

Arun Thenappan; Ihab Halaweish; Rajen Mody; Ethan A. Smith; James D. Geiger; Peter F. Ehrlich; Rama Jasty Rao; Raymond J. Hutchinson; Gregory A. Yanik; Raja Rabah; Amer Heider; Tammy Stoll; Erika A. Newman

Optimal cancer care requires a multidisciplinary approach. The purpose of the current study was to evaluate the impact of a multidisciplinary tumor board on the treatment plans of children with solid tumors.


British Journal of Oral & Maxillofacial Surgery | 2016

Foregut duplication cyst of the floor of mouth in a neonate: case report

Jason Schrotenboer; Amer Heider; Ethan A. Smith; Sharon Aronovich

Congenital oral masses may interfere with vital functions such as respiration and deglutition in neonates. We report a congenital heterotopic oral gastrointestinal cyst that caused failure to thrive. A working knowledge of the differential diagnosis and pathophysiology of this can guide the clinician in its evaluation and management.


Urology | 2018

Prepubertal Malignant Large Cell Calcifying Sertoli Cell Tumor of the Testis

Guanqun Li; Matthew Lee; Kate H. Kraft; Amer Heider

An otherwise healthy 7-year-old boy was diagnosed with malignant large cell calcifying Sertoli cell tumor (LCCSCT) of the testis. He underwent attempted partial orchiectomy with conversion to radical orchiectomy due to suspected malignancy on intraoperative frozen section. There was no lymph node or visceral metastases. To our knowledge, this is the first report of malignant LCCSCT in the prepubertal population. LCCSCT of the testis is an extremely rare neoplasm, with low malignant potential. Malignant cases are exclusively reported previously in the adult population. We report the first case of malignant LCCSCT in a pediatric patient. We review the literatures and discuss the clinical, pathologic features and treatments of malignant LCCSCT.


Journal of Hand Surgery (European Volume) | 2017

Unusual Presentation of Infantile Myofibroma in the Deep Palm of a Child: A Case Report and Discussion of the Differential Diagnosis

Matthew S. Brown; Amer Heider; Kevin C. Chung

Infantile myofibroma or myofibromatosis is a myofibroblastic and fibroblastic proliferation that is most commonly reported in children younger than 2 years of age. It is a benign process composed histologically of a biphasic pattern of spindle-shaped cells surrounding a zone of less differentiated cells in a hemangiopericytoma-like pattern. We report this tumor in a unique presentation in the deep palm of a 2-year-old child without skin ulceration and with an intimate association with the median nerve. The well-circumscribed nature of the tumor facilitated complete excision with neural preservation. Final pathology was consistent with an unusual type of myofibroma or myofibromatosis. Conservative management with partial excision has been advocated for these masses because of potential surgical morbidity and its benign nature. This case report highlights the differential diagnosis of uncommon soft tissue tumors in the pediatric hand as well as the importance of a surgeons surgical assessment in guiding treatment.

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Jonathan R. Dillman

Cincinnati Children's Hospital Medical Center

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Raja Rabah

Wayne State University

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Rajen Mody

University of Michigan

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Ranjith Vellody

George Washington University

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