title: Failure to recognize multiple endocrine neoplasia 2B: more common than we think?
abstract: BACKGROUND
  Multiple endocrine neoplasia 2B (MEN2B) has a classic childhood phenotypic presentation characterized by mucosal neuromas and marfanoid habitus. However, the diagnosis of MEN2B is often delayed beyond childhood, at which time medullary thyroid carcinoma (MTC) may be regionally advanced or metastatic. We examined the extent of this delay and its impact on the treatment of MTC.
  
  
  METHODS
  Patients in the MEN database were retrospectively analyzed to determine the age at first presentation for a MEN2B-related complaint and the subsequent time to correct diagnosis. Operative and pathology reports were reviewed to determine the extent of thyroidectomy and cervical lymphadenectomy during the initial and subsequent neck operations.
  
  
  RESULTS
  We identified 22 patients with MEN2B, 20 were de novo cases and a M918T RET gene mutation was confirmed in 18 of the 22 patients. Median age at diagnosis of MTC was 13 years (range 6-25 years). The median delay in diagnosis was 26 months (range 0-18 years). Persistent local-regional MTC was present following the initial cervical operation in 12 of 22 patients (55%); including 4 of 13 with MEN2B diagnosed prior to initial surgery and 8 of 9 with MEN2B diagnosed after initial surgery.
  
  
  CONCLUSIONS
  Most patients displayed phenotypic characteristics of MEN2B long before the correct diagnosis was made. Half of the patients failed to undergo complete resection of MTC at their initial thyroid surgery. Early recognition of the MEN2B phenotype with a thoughtful approach to preoperative staging and surgery will maximize control of MTC and minimize the need for reoperation.
authors.affiliation: Department of Surgical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
authors.forename: Curtis J
authors.initials: CJ
authors.lastname: Wray
authors.forename: Thereasa A
authors.initials: TA
authors.lastname: Rich
authors.forename: Steven G
authors.initials: SG
authors.lastname: Waguespack
authors.forename: Jeffrey E
authors.initials: JE
authors.lastname: Lee
authors.forename: Nancy D
authors.initials: ND
authors.lastname: Perrier
authors.forename: Douglas B
authors.initials: DB
authors.lastname: Evans
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D018276:Carcinoma, Medullary / Q000175:diagnosis* / Q000601:surgery; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008197:Lymph Node Excision; D008297:Male; D018814:Multiple Endocrine Neoplasia Type 2b / Q000175:diagnosis* / Q000601:surgery; D009154:Mutation / Q000235:genetics; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis / Q000601:surgery; D051096:Proto-Oncogene Proteins c-ret / Q000235:genetics / Q000378:metabolism; D012189:Retrospective Studies; D013964:Thyroid Neoplasms / Q000175:diagnosis* / Q000601:surgery; D013965:Thyroidectomy; D013997:Time Factors
chemical_list: D051096:Proto-Oncogene Proteins c-ret; C099282:RET protein, human