title: Multiple endocrine neoplasia type 2B diagnosed on suction rectal biopsy in infancy: a report of 2 cases.
abstract: Suction rectal biopsies in a newborn and a 10-month-old infant presenting with intestinal obstruction showed marked increase in neurons and nerve bundles in the submucosa. Although there were no syndromic features or a positive family history, mutation analysis of the RET proto-oncogene showed a de novo germline Met918Thr mutation in both patients, confirming the diagnosis of multiple endocrine neoplasia type 2B (MEN 2B). Thyroidectomy was performed at 9 and 14 months, showing medullary carcinoma and focal prominent C-cell hyperplasia, respectively. These 2 cases are presented to emphasize that when the submucosal plexus is obviously and prominently increased in suction rectal biopsies, diffuse intestinal ganglioneuromatosis should be considered. As this can be associated with genetic conditions, especially MEN 2B, it is crucial that further investigations be performed to ensure proper patient management, such as early thyroidectomy.
authors.affiliation: Department of Anatomical Pathology, Royal Children's Hospital, Flemington Road, Parkville, VIC 3052, Australia.
authors.forename: Minzhi
authors.initials: M
authors.lastname: Yin
authors.forename: Sebastian K
authors.initials: SK
authors.lastname: King
authors.forename: John M
authors.initials: JM
authors.lastname: Hutson
authors.forename: Chung Wo
authors.initials: CW
authors.lastname: Chow
mesh_terms: D001707:Biopsy, Needle / Q000379:methods*; D004252:DNA Mutational Analysis; D006801:Humans; D006965:Hyperplasia; D007223:Infant; D007231:Infant, Newborn; D007415:Intestinal Obstruction / Q000209:etiology / Q000473:pathology; D008297:Male; D018814:Multiple Endocrine Neoplasia Type 2b / Q000150:complications / Q000175:diagnosis* / Q000601:surgery; D009154:Mutation; D009412:Nerve Fibers / Q000473:pathology; D009474:Neurons / Q000473:pathology; D000090063:Proto-Oncogene Mas; D051096:Proto-Oncogene Proteins c-ret / Q000235:genetics; D012007:Rectum / Q000473:pathology*; D013368:Submucous Plexus / Q000473:pathology; D013396:Suction / Q000295:instrumentation / Q000379:methods; D013964:Thyroid Neoplasms / Q000473:pathology / Q000601:surgery; D013965:Thyroidectomy
chemical_list: C000715470:MAS1 protein, human; D000090063:Proto-Oncogene Mas; D051096:Proto-Oncogene Proteins c-ret; C099282:RET protein, human