title: Rapid on-site evaluation by endosonographer during endoscopic ultrasound-guided fine needle aspiration for pancreatic solid masses.
abstract: OBJECTIVE
  Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is an established diagnostic method for patients with suspected pancreatic ductal carcinoma. Rapid on-site evaluation (ROSE) has been reported to improve the accuracy. However, an on-site cytopathologist is not routinely available in many institutions. One of the solutions may be ROSE by endosonographer. The aim was to examine whether diagnostic accuracy increases through ROSE by endosonographer using our cytological criteria.
  
  
  METHODS
  Patients who underwent EUS-FNA of solid pancreatic masses from January 2006 to August 2009 (n = 53, period 1) and September 2009 to April 2011 (n = 85, period 2) were retrospectively identified. Before initiating ROSE at the start of period 2, two endosonographers underwent training for cytological interpretation, which was focused on four cytological features of pancreatic ductal carcinoma: anisonucleosis, nuclear membrane irregularity, overlapping, and enlargement. During EUS-FNA in period 2, endosonographers classified the Diff-Quik smears under three atypical grades and evaluated the adequacy. All diagnoses were made by one pathologist without knowledge of clinical information.
  
  
  RESULTS
  The rate of "inconclusive" diagnoses, interpreted as "suspicious," "atypical," and "inadequate for diagnosis" was reduced from 26.4% in period 1 to 8.2% in period 2 (P = 0.004). Moreover, diagnostic accuracy was increased from 69.2% in period 1 to 91.8% in period 2 (P < 0.001).
  
  
  CONCLUSIONS
  This cytological grading system used in ROSE by endosonographers is invaluable for the diagnosis of pancreatic solid masses.
authors.affiliation: Fourth Department of Internal Medicine, Sapporo Medical University School of Medicine, Sapporo, Hokkaido, Japan. thayashi69@sapmed.ac.jp
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Hayashi
authors.forename: Hirotoshi
authors.initials: H
authors.lastname: Ishiwatari
authors.forename: Makoto
authors.initials: M
authors.lastname: Yoshida
authors.forename: Michihiro
authors.initials: M
authors.lastname: Ono
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Sato
authors.forename: Koji
authors.initials: K
authors.lastname: Miyanishi
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Sato
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Kobune
authors.forename: Rishu
authors.initials: R
authors.lastname: Takimoto
authors.forename: Tomoko
authors.initials: T
authors.lastname: Mitsuhashi
authors.forename: Hiroko
authors.initials: H
authors.lastname: Asanuma
authors.forename: Jiro
authors.initials: J
authors.lastname: Ogino
authors.forename: Tadashi
authors.initials: T
authors.lastname: Hasegawa
authors.forename: Tomoko
authors.initials: T
authors.lastname: Sonoda
authors.forename: Junji
authors.initials: J
authors.lastname: Kato
mesh_terms: D000368:Aged; D021441:Carcinoma, Pancreatic Ductal / Q000000981:diagnostic imaging* / Q000473:pathology; D042241:Early Diagnosis; D061765:Endoscopic Ultrasound-Guided Fine Needle Aspiration; D019160:Endosonography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D010190:Pancreatic Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D015203:Reproducibility of Results; D012189:Retrospective Studies