title: Diagnostic accuracy of bronchial brush cytology and the added value of immunohistochemistry and fluorescence in situ hybridization of pulmonary neuroendocrine tumors.
abstract: BACKGROUND
  Bronchial brush (BB) cytology carries low sensitivity for detecting neuroendocrine carcinomas (NECs), including typical carcinoid (TC) tumors of the lung. We aimed to investigate the detection of neuroendocrine tumors including TC through BB routine cytology cell block (CB), immunohistochemistry (IHC), and fluorescence in situ hybridization (FISH).
  
  
  METHODS
  A SNOMED search showed 187 lung biopsy or resection specimens from 2008 through 2011 containing neuroendocrine or carcinoid in the diagnosis. Residual BB specimens retained in PreservCyt were used to prepare a ThinPrep slide for FISH analysis. CBs were stained with H and E and IHC for chromogranin and synaptophysin.
  
  
  RESULTS
  Of the 187 cases, 16 had residual BB material available within 1 year of diagnosis and were used in CB preparation for IHC and FISH slides. Cytologic evaluation determined 1 case positive for malignancy (small cell lung carcinoma [SCLC]), 1 suspicious for adenocarcinoma, and 14 negative for malignancy. On the basis of histologic diagnosis, FISH was performed. SCLC showed polysomy (86% abnormal cells); 2 TC tumors showed a gain of 7p12 (15% abnormal cells) and a gain of 5q15 (72% abnormal cells), respectively. Two cases had CBs with positive immunoreactivity for chromogranin and synaptophysin. The sensitivity for detection of NEC was 18.8%, 15.4%, and 25% for cytologic evaluation, CB, and FISH, respectively.
  
  
  CONCLUSIONS
  Neuroendocrine tumors, including TC are difficult to detect with BB cytologic evaluation, most likely because tumor cells lack in the specimen. Assessment of further studies is needed to explore the role of cytology and ancillary methods for detection of these tumors.
authors.affiliation: Address: Pathology and Laboratory Medicine Institute, Cleveland Clinic, Cleveland, OH, United States.
authors.forename: Jordan P
authors.initials: JP
authors.lastname: Reynolds
authors.affiliation: Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, United States.
authors.forename: Jesse S
authors.initials: JS
authors.lastname: Voss
authors.affiliation: Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, United States.
authors.forename: Shannon M
authors.initials: SM
authors.lastname: Brankley
authors.affiliation: Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, United States.
authors.forename: Jill M
authors.initials: JM
authors.lastname: Caudill
authors.affiliation: Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, United States.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Henry
authors.affiliation: Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, United States.
authors.forename: Amy C
authors.initials: AC
authors.lastname: Clayton
authors.affiliation: Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, United States.
authors.forename: Kevin C
authors.initials: KC
authors.lastname: Halling
authors.affiliation: Department of Laboratory Medicine and Pathology, Mayo Clinic, Jacksonville, FL, United States.
authors.forename: Aziza
authors.initials: A
authors.lastname: Nassar
keywords: Ancillary studies; carcinoid tumor; cytology; endobronchial sampling; pulmonary