Neonatal Gardner fibroma: a sentinel presentation of severe familial adenomatous polyposis

Imaging palpable tumors in pediatrics: Part 2

Palpable tumors in children are a common reason for consulting a radiologist. The origin of these lesions varies widely, and although they are common, classic radiology books do not cover some of them. This series of two articles aims to review the clinical and radiological characteristics of a selection of palpable tumors in children that radiologists need to be familiar with.

Identification of aggressive Gardner syndrome phenotype associated with a de novo APC variant, c.4666dup

Gardner syndrome describes a variant phenotype of familial adenomatous polyposis (FAP), primarily characterized by extracolonic lesions including osteomas, dental abnormalities, epidermal cysts, and soft tissue tumors. We describe a 2-yr-old boy presenting with a 2-cm soft tissue mass of the forehead. Pathologic evaluation revealed a nuchal-type/Gardner-associated fibroma. Sequencing of the APC gene revealed a pathologic variant c.4666dupA. Parental sequencing of both blood and buccal tissue supported the de novo occurrence of this pathologic variant. Further imaging revealed a number of additional lesions including a large lumbar paraspinal desmoid, a 1-cm palpable lesion posterior to the left knee, firm lesions on bilateral heels, and multiple subdermal lesions. Colonoscopy was negative. This case illustrates a genetic variant of Gardner syndrome resulting in an aggressive early childhood phenotype and highlights the need for an individualized approach to treatment.

Gardener-associated fibroma: an unusual cause of upper airway obstruction

We present the first case of upper airway obstruction secondary to a retropharyngeal Gardner-associated fibroma (GAF). A 16-month-old infant presented with a 3-month history of worsening dyspnoea and apnoeic episodes. Examination revealed stridor and left-sided retropharyngeal asymmetry. MRI demonstrated a mass in the retropharynx. Tracheostomy and pharyngeal biopsy under anaesthesia were performed, and histology confirmed a diagnosis of GAF. The mass was excised using a transcervical approach, and postoperative recovery was unremarkable. GAF is associated with Gardner's syndrome (GS) and familial adenomatous polyposis (FAP), both of which are associated with multiple colonic polyps and increased risk of colorectal malignancy. Subsequent testing for an APC mutation seen in GS and FAP was negative in our patient. The details of this unusual presentation of a rare disease are given in addition to a review of the literature.

Upper GI involvement in children with familial adenomatous polyposis syndrome: single-center experience and meta-analysis of the literature

BACKGROUND AND AIMS

Familial adenomatous polyposis (FAP) is a hereditary syndrome that can affect the entire GI tract. Current screening recommendations include EGD starting at age 25 to 30 years or earlier in symptomatic patients. However, few reports describe upper GI tract involvement in children with FAP that support the notion of early screening. The aim of our study is to understand the prevalence and severity of upper GI involvement in children with FAP.

METHODS

We performed a retrospective review of the Mayo Clinic records, between 1992 and 2016, to identify children with the diagnosis of FAP who underwent EGD examinations. A systematic review of the literature was performed to include published studies reporting children with FAP and upper GI findings.

RESULTS

The retrospective study included 69 children with a mean age of 13.5 years (range, 3-18). Thirty-six children (52%) had duodenal adenoma with low-grade dysplasia. Five children required an ampullectomy secondary to enlarged and polypoid ampullas. Combined with published studies, a total of 206 children with upper GI findings were identified, of which 87 (42%) had duodenal adenoma (1 had high-grade dysplasia). Meta-analysis of 5 series demonstrated duodenal adenoma detection rate of 39% (95% confidence interval, 21%-57%; I² = 85%).

CONCLUSIONS

The available data to date show that children with FAP can have clinically relevant lesions in the upper GI tract earlier than previously foreseen, suggesting that earlier screening may be indicated. Larger multicenter prospective studies are needed to determine the best approach and optimal age for EGD screening in children with FAP.

From Gardner fibroma diagnosis to constitutional APC mutation detection: a one-way street

We report a young child without a family history of FAP, who promptly underwent APC testing after the histological confirmation of a paraspinal GAF that was not isolated. Our case report reinforces the suggestion advanced by previous authors for an APC analysis in all patients with GAF.

Guideline for wireless capsule endoscopy in children and adolescents: A consensus document by the SEGHNP (Spanish Society for Pediatric Gastroenterology, Hepatology, and Nutrition) and the SEPD (Spanish Society for Digestive Diseases)

INTRODUCTION

Capsule Endoscopy (CE) in children has limitations based mainly on age. The objective of this consensus was reviewing the scientific evidence.

MATERIAL AND METHODS

Some experts from the Spanish Society of Gastroenterology (SEPD) and Spanish Society for Pediatric Gastroenterology, Hepatology, and Nutrition (SEGHNP) were invited to answer different issues about CE in children. These sections were: a) Indications, contraindications and limitations; b) efficacy of CE in different clinical scenarios; c) CE performance; d) CE-related complications; e) Patency Capsule; and f) colon capsule endoscopy. They reviewed relevant questions on each topic.

RESULTS

The main indication is Crohn's disease (CD). There is no contraindication for the age and in the event that the patient not to swallow it, it should be administered under deep sedation with endoscopy and specific device. The CE is useful in CD, for the management of OGIB in children and in Peutz-Jeghers syndrome (in this indication has the most effectiveness). The main complication is retention, which should be specially taken into account in cases of CD already diagnosed with malnutrition. A preparation regimen based on a low volume of polyethylene glycol (PEG) the day before plus simethicone on the same day is the best one in terms of cleanliness although does not improve the results of the CE procedure.

CONCLUSIONS

CE is safe and useful in children. Indications are similar to those of adults, the main one is CD to establish both a diagnosis and disease extension. Moreover, only few limitations are detected in children.

Neonatal Gardner Fibroma Leads to Detection of Familial Adenomatous Polyposis: Two Case Reports

Gardner fibromas (GFs) have only recently been described as poorly circumscribed tumor-like lesions, which are exceedingly rare in children. GFs are associated with APC gene mutations and therefore with familial adenomatous polyposis (FAP). So far there is only very limited literature on GF in the neonatal period. We present two children with GF diagnosed at birth and subsequent FAP with very different clinical courses. In one case, the disease led to extensive surgery of the thoracic wall and detection of FAP in the father with the need of immediate proctocolectomy. In the other patient (with a positive family history for FAP) the disease remained stable. Our cases indicate that the diagnosis of GF in the neonatal period requires the exclusion of FAP both in the child as well as the parents. Since the clinical behavior of GF cannot be predicted, continuous monitoring is mandatory. Depending on tumor site and growth, individual therapeutic options must be thoroughly considered. Surgical resection, if necessary, has to be inevitably total to prevent recurrence.

Gardner Fibroma: Clinical and Histopathologic Implications of Germline APC Mutation Association

The proportion and clinical characteristics of Gardner fibromas (GAFs) that are sporadic versus familial adenomatous polyposis (FAP)-associated have not been clearly established. We report on 7 patients diagnosed with GAF who underwent APC sequencing and duplication/deletion testing. Three (43%) were found to have underlying APC germline perturbations consistent with FAP; these patients had multifocal (1) or large; unresectable (2) GAFs. The 4 patients with negative APC testing each had a single resectable GAF. β-catenin reactivity was noted in all FAP-associated GAFs and in 1/4 APC wild-type cases. FAP-associated GAFs may be less common than sporadic GAFs and can demonstrate clinically distinct features.

Risk-reduction surgery in pediatric surgical oncology: A perspective

OBJECTIVE

A small percentage of pediatric solid cancers arise as a result of clearly identified inherited predisposition syndromes and nongenetic lesions. Evidence supports preemptive surgery for children with genetic [multiple endocrine neoplasia type 2 (MEN2), familial adenomatous polyposis syndrome (FAP), hereditary nonpolyposis colorectal cancer (HNPCC), and hereditary diffuse gastric cancer (HDGC) and nongenetic [thyroglossal duct cysts (TGDC), congenital pulmonary airway malformations (CPAM), alimentary tract duplication cysts (ATDC), and congenital choledochal cysts (CCC)] developmental anomalies. Our aim was to explore the utility of risk reduction surgery to treat and prevent cancer in children.

METHODS

A systematic review of the available peer-reviewed literature on PubMed was performed using a PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) search strategy, where possible. Search items included "risk reduction surgery", "hereditary cancer predisposition syndrome", "multiple endocrine neoplasia type 2", "familial adenomatous polyposis", "hereditary nonpolyposis colorectal cancer", "hereditary diffuse gastric cancer", "thyroglossal duct cysts", congenital pulmonary airway malformations", "alimentary tract duplication cysts", "malignant transformation", and "guidelines".

RESULTS

We identified 67 articles that met the inclusion criteria describing the indications for prophylactic surgery in surgical oncology. For the genetic predisposition syndromes, 7 studies were related to professional endorsed guidelines, 7 were related to surgery for MEN2, 11 were related to colectomy for FAP, 6 were related to colectomy for HNPCC, and 12 related to gastrectomy for HDGC. Articles for the nongenetic lesions included 5 for techniques related to TGDC resection, 9 for surgery for CPAMs, and 10 for resection of ATDCs. Guidelines and strategies varied significantly especially related to the extent and timing of surgical intervention; the exception was for the timing of thyroidectomy in children with MEN2.

CONCLUSION

Current evidence supporting prophylactic surgery in the management of pediatric cancer predisposition syndromes and nongenetic lesions is best delineated for thyroidectomy to prevent medullary thyroid cancer in children with MEN2 (Strength of Recommendation Grade B/C). Despite the lack of pediatric specific evidence-based recommendations regarding the appropriate extent and timing for risk-reduction surgery for FAP, HNPCC, HDGC and nongenetic anomalies, our review represents an opportunity towards understanding the postgenomic development of these lesions and provides current indications and techniques for preemptive cancer prevention surgery in children.

Identification of previously unrecognized FAP in children with Gardner fibroma

Fibromatous soft tissue lesions, namely desmoid-type fibromatosis and Gardner fibroma, may occur sporadically or as a result of inherited predisposition (as part of familial adenomatous polyposis, FAP). Whereas desmoid-type fibromatosis often present β-catenin overexpression (by activating CTNNB1 somatic variants or APC biallelic inactivation), the pathogenetic mechanisms in Gardner fibroma are unknown. We characterized in detail Gardner fibromas diagnosed in two infants to evaluate their role as sentinel lesions of previously unrecognized FAP. In the first infant we found a 5q deletion including APC in the tumor and the novel APC variant c.4687dup in constitutional DNA. In the second infant we found the c.5826_5829del and c.1678A>T APC variants in constitutional and tumor DNA, respectively. None of the constitutional APC variants occurred de novo and both tumors showed nuclear staining for β-catenin and no CTNNB1 variants. We present the first comprehensive characterization of the pathogenetic mechanisms of Gardner fibroma, which may be a sentinel lesion of previously unrecognized FAP families.