title: Tumor diameter and Ki-67 expression in biopsy could be diagnostic markers discriminating from adenoma and early stage cancer in patients with ampullary tumors.
abstract: BACKGROUND
  Ampullary early stage cancer (early CA) potentially harbors lymphovascular invasion; there are few data on markers that could differentiate adenoma and early CA.
  
  
  OBJECTIVE
  To investigate those markers, we compared the tumor diameter and Ki-67 expression in endoscopy biopsy specimens of adenoma with those of early CA.
  
  
  METHODS
  Patients on whom endoscopic papillectomy (EP) was performed (n = 35) with histopathologically proven adenomas and with low/high grade dysplasia and early CA were studied. We made pre-procedure evaluations of ampullary tumors by using endoscopic ultrasonography (EUS) and transpapillary intraductal ultrasonography. Tumor diameter was measured by EUS. Endoscopic biopsy using immunostaining of Ki-67 labeling index (LI) prior to EP were evaluated.
  
  
  RESULTS
  The areas under the receiver-operating characteristic (AUROC) curves for tumor diameter and Ki-67 expression were 0.824 and 0.873, respectively. Cut-off values calculated based on AUROC data were 15 mm in tumor diameter and 32 cells/high-power field (HPF) in Ki-67. Early CA (n = 11) was diagnosed by using a cut-off value for tumor diameter in 8 out of 11 patients (sensitivity 72.7 %, specificity 66.7 %, accuracy 68.6 %). Significant infiltration of the major duodenal papilla by Ki-67 positive tumor cells (>31/HPF) was recognized in 8 of the 11 patients with early CA (sensitivity 100 %, specificity 54.2 %, accuracy 62.9 %).
  
  
  CONCLUSIONS
  Observation of tumor diameter and Ki-67 LI would be helpful for safety EP. EP should not be indicated for ampullary tumors more than 15 mm in diameter and/or Ki-67 LI 31/HPF.
authors: Department of Gastroenterology, Yokohama City University, Graduate School of Medicine, Fukuura 3-9, Kanazawa, Yokohama 236-0004, Japan. kubotak@yokohama-cu.ac.jp
authors: Kensuke
authors: K
authors: Kubota
authors: Yuji
authors: Y
authors: Fujita
authors: Takamitsu
authors: T
authors: Sato
authors: Seitaro
authors: S
authors: Watanabe
authors: Kunihiro
authors: K
authors: Hosono
authors: Masato
authors: M
authors: Yoneda
authors: Hiroyuki
authors: H
authors: Kirikoshi
authors: Kantaro
authors: K
authors: Hisatomi
authors: Nobuyuki
authors: N
authors: Matsuhashi
authors: Itaru
authors: I
authors: Endo
authors: Yoshiaki
authors: Y
authors: Inayama
authors: Atsushi
authors: A
authors: Nakajima
mesh_terms: D000236:Adenoma / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000032:analysis; D001706:Biopsy; D002760:Cholangiopancreatography, Endoscopic Retrograde; D003138:Common Bile Duct Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery*; D004724:Endoscopy; D019160:Endosonography; D005260:Female; D006801:Humans; D019394:Ki-67 Antigen / Q000032:analysis*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D015607:Stents
chemical_list: D015415:Biomarkers; D019394:Ki-67 Antigen