title: Bronchopulmonary Neuroendocrine Neoplasms and Their Precursor Lesions in Multiple Endocrine Neoplasia Type 1.
abstract: The prevalence and clinical behavior of bronchopulmonary neuroendocrine tumors (bNET) associated with multiple endocrine neoplasia type 1 (MEN1) are not well defined. This study aimed to determine the prevalence, potential precursor lesions and prognosis of bNET in patients with MEN1.
  
  
  
  A database of 75 prospectively collected MEN1 cases was retrospectively analyzed for bNET. Patient characteristics, imaging and treatment were evaluated. Resection specimens of operated patients were reassessed by two specialized pathologists. Available CT scans of the whole cohort were reviewed to determine the prevalence of bronchopulmonary nodules.
  
  
  
  Five of the 75 MEN1 patients (6.6%; 2 male, 3 female) developed histologically confirmed bNET after a median follow-up of 134 months. The median age at diagnosis of bNET was 47 years (range 31-67), and all patients were asymptomatic. Four patients underwent anatomic lung resections with lymphadenectomy; the remaining patient with multiple lesions had only a wedge resection of the largest bNET. Tumor sizes ranged from 7 to 32 mm in diameter, and all bNET were well differentiated. Two patients had lymph node metastases. Two of 4 reevaluated resection specimens revealed multifocal bNET, and 3 specimens showed tumorlets (up to 3) associated with multifocal areas of a neuroendocrine cell hyperplasia within the subsegmental bronchi. One bNET-related death (1.3%) occurred during long-term follow-up. Review of the available CT scans of the patients without proven bNET revealed small bronchopulmonary lesions (≥3 mm) in 16 of 53 cases (30.2%).
  
  
  
  bNET in MEN1 might be more common than previously recognized. Their natural course seems to be rather benign. Multifocal tumorlets and multifocal neuroendocrine cell hyperplasia might represent their precursor lesions.
authors.affiliation: Department of Visceral, Thoracic and Vascular Surgery, Philipps-Universitx00E4;t Marburg, Marburg, Germany.
authors.forename: Detlef K
authors.initials: DK
authors.lastname: Bartsch
authors.forename: Max B
authors.initials: MB
authors.lastname: Albers
authors.forename: Caroline L
authors.initials: CL
authors.lastname: Lopez
authors.forename: Jonas C
authors.initials: JC
authors.lastname: Apitzsch
authors.forename: Eduard M
authors.initials: EM
authors.lastname: Walthers
authors.forename: Ludger
authors.initials: L
authors.lastname: Fink
authors.forename: Volker
authors.initials: V
authors.lastname: Fendrich
authors.forename: Emily P
authors.initials: EP
authors.lastname: Slater
authors.forename: Jens
authors.initials: J
authors.lastname: Waldmann
authors.forename: Martin
authors.initials: M
authors.lastname: Anlauf
mesh_terms: D000328:Adult; D000368:Aged; D001984:Bronchial Neoplasms / Q000150:complications* / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000473:pathology; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000150:complications* / Q000453:epidemiology* / Q000473:pathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D018761:Multiple Endocrine Neoplasia Type 1 / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000473:pathology / Q000601:surgery; D018358:Neuroendocrine Tumors / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D014055:Tomography, Emission-Computed