title: Endoscopic ultrasound-guided fine needle tissue acquisition biopsy samples do not allow a reliable proliferation assessment of gastrointestinal stromal tumours.
abstract: BACKGROUND
  Current prognostication of gastrointestinal stromal tumours is validated on/applies to resected tumours, mainly because surgery is recommended whenever possible. However, pre-treatment prognostication is increasingly warranted, considering the follow-up strategy recently admitted for expectedly low-risk tumours and the possible distinctive molecular features/spontaneous regression of some small cases.
  
  
  OBJECTIVE
  To investigate whether endoscopic ultrasound-guided fine-needle tissue acquisition-biopsies reflect prognosticators of resected gastrointestinal stromal tumours, for possibly developing reliable pre-treatment prognostic criteria.
  
  
  METHODS
  The applicability/reliability of mitotic index/5mm(2) and MIB1 proliferative index/1000 cells were tested in 35 endoscopic ultrasound-guided fine-needle tissue acquisition-biopsies diagnosed as gastrointestinal stromal tumour, subsequently resected without intervening therapy, consecutively collected in thirty months. Size and mitotic/proliferative indexes were compared with resection specimens. The feasibility of bioptic genotyping was also tested.
  
  
  RESULTS
  35 patients were studied (45.7% males; mean age 61.6 years, range 26-83 years). Mitotic/proliferative indexes were determinable in 68.6%/88.6% of biopsies, respectively; they were nevertheless underestimated, as happened with endoscopic ultrasound-determined tumour size. Bioptic genotyping revealed reliable.
  
  
  CONCLUSIONS
  Endoscopic ultrasound-guided fine-needle tissue acquisition does not reliably reflect gastrointestinal stromal tumours' proliferation and size. Alternative parameters should be validated for a pre-surgical prognostic classification. Considering the emerging potentially prognostic genetic markers in gastrointestinal stromal tumours, the reliability of bioptic genotyping is a promising result.
authors.affiliation: Department of Pathology, Catholic University, Rome, Italy. Electronic address: riccardoricci@rm.unicatt.it.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Ricci
authors.affiliation: Department of Pathology, Catholic University, Rome, Italy.
authors.forename: Gaia
authors.initials: G
authors.lastname: Chiarello
authors.affiliation: Digestive Endoscopy Unit, Catholic University, Rome, Italy.
authors.forename: Fabia
authors.initials: F
authors.lastname: Attili
authors.affiliation: Gastroenterology Unit, Department of Medical and Surgical Sciences, S. Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Fuccio
authors.affiliation: Department of Surgery, Catholic University, Rome, Italy.
authors.forename: Sergio
authors.initials: S
authors.lastname: Alfieri
authors.affiliation: Department of Surgery, Catholic University, Rome, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Persiani
authors.affiliation: Digestive Endoscopy Unit, Catholic University, Rome, Italy.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Di Pietro
authors.affiliation: Department of Pathology, Catholic University, Rome, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Martini
authors.affiliation: Digestive Endoscopy Unit, Catholic University, Rome, Italy.
authors.forename: Guido
authors.initials: G
authors.lastname: Costamagna
authors.affiliation: Department of Pathology, Catholic University, Rome, Italy.
authors.forename: Luigi M
authors.initials: LM
authors.lastname: Larocca
authors.affiliation: Digestive Endoscopy Unit, Catholic University, Rome, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Larghi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044963:Biopsy, Fine-Needle / Q000379:methods*; D049109:Cell Proliferation; D019160:Endosonography; D005240:Feasibility Studies; D005260:Female; D005770:Gastrointestinal Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D046152:Gastrointestinal Stromal Tumors / Q000000981:diagnostic imaging / Q000473:pathology*; D006801:Humans; D061705:Image-Guided Biopsy / Q000379:methods*; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012189:Retrospective Studies
keywords: Biopsy; Gastrointestinal stromal tumour; Prognosis; Proliferation