title: Dynamic computed tomography is useful for prediction of pathological grade in pancreatic neuroendocrine neoplasm.
abstract: OBJECTIVE
  Pathological grading is important in defining the therapeutic strategy in pancreatic neuroendocrine neoplasm (PNEN) but is difficult for unresectable cases. Endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA) is useful in the diagnosis of PNEN, but its usefulness for pathological grading is not well established. No studies have examined the diagnostic ability of dynamic computed tomography (CT) for pathological grading of PNEN. We investigated the usefulness of EUS-FNA and dynamic CT in the diagnosis and pathological grading of PNEN.
  
  
  METHODS
  In this retrospective study, 39 PNEN patients finally diagnosed via EUS-FNA and/or surgical resection underwent dynamic CT. Pathological samples were diagnosed based on WHO2010; staging was based on the European Neuroendocrine Tumor Society classification. The proportion of the quantification value in the tumor to the pancreatic parenchyma in arterial phase was defined as the CT ratio. Immunohistochemical staining with CD31 was performed to evaluate microvessel density (MVD). We evaluated the relationship between pathological grade, CT ratio, and MVD.
  
  
  RESULTS
  By using EUS-FNA, 35 of 39 (90%) cases were diagnosed as PNEN. As for pathological grade, 15 of 35 (43%) cases could be identified correctly. CT ratio could predict pathological Grade 3 disease. The sensitivity, specificity, and diagnostic accuracy were 100%, 94%, and 95%. MVD was significantly correlated with CT ratio (r = 0.83, P < 0.0001) and pathological grade (P = 0.0074).
  
  
  CONCLUSIONS
  Computed tomography ratio has a relationship with pathological grade in PNEN, which would help decide therapeutic strategy in unresectable cases and cases in which pathological grading is difficult.
authors.affiliation: Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science, Okayama, Japan.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Horiguchi
authors.affiliation: Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science, Okayama, Japan.
authors.forename: Hironari
authors.initials: H
authors.lastname: Kato
authors.affiliation: Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science, Okayama, Japan.
authors.forename: Hidenori
authors.initials: H
authors.lastname: Shiraha
authors.affiliation: Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science, Okayama, Japan.
authors.forename: Koichiro
authors.initials: K
authors.lastname: Tsutsumi
authors.affiliation: Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science, Okayama, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Yamamoto
authors.affiliation: Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science, Okayama, Japan.
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Matsumoto
authors.affiliation: Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science, Okayama, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Tomoda
authors.affiliation: Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science, Okayama, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Uchida
authors.affiliation: Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science, Okayama, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Akimoto
authors.affiliation: Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science, Okayama, Japan.
authors.forename: Syou
authors.initials: S
authors.lastname: Mizukawa
authors.affiliation: Department of Pathology and Oncology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
authors.forename: Takehiro
authors.initials: T
authors.lastname: Tanaka
authors.affiliation: Department of Pathology and Oncology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Ichimura
authors.affiliation: Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science, Okayama, Japan.
authors.forename: Akinobu
authors.initials: A
authors.lastname: Takaki
authors.affiliation: Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
authors.forename: Takahito
authors.initials: T
authors.lastname: Yagi
authors.affiliation: Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science, Okayama, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Okada
mesh_terms: D000328:Adult; D000368:Aged; D061765:Endoscopic Ultrasound-Guided Fine Needle Aspiration; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D018358:Neuroendocrine Tumors / Q000000981:diagnostic imaging* / Q000473:pathology*; D010190:Pancreatic Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*
keywords: WHO2010; dynamic CT; microvessel density; pancreatic neuroendocrine neoplasm; pathological grade