title: Expression of cyclooxygenase-2 (COX-2) in pituitary tumours.
abstract: BACKGROUND
  Microvessel density in angiogenesis is regarded as a prognostic factor of tumour invasiveness, independent of cell proliferation. In recent studies of pituitary tumours, correlation between the expression of cyclooxygenase-2 (COX-2) and micro-vascularization density and microvessel surface density has been established. We studied the expression of COX-2 in different types of pituitary adenomas to determine the usefulness of COX-2 expression as a prognostic factor of tumour progression or recurrence in patients with hypophyseal tumours.
  
  
  METHODS
  We retrospectively studied a group of 60 patients of mean age 46.7±17.6 (range, 18 to 85) years who underwent pituitary tumour surgery. Expression of COX-2, as determined by immunohistochemistry, was analyzed in relation to histopathology features of tumour, clinical symptoms, MR imaging and post-operative recurrence/progression of disease.
  
  
  RESULTS
  COX-2 was expressed in adenomas of 87% of patients, with a median index value of 57.5% [IQR=60.5]. Highest COX-2 expression was observed in hormonally inactive adenomas and gonadotropinomas and lowest in prolactinomas. We found no differences in COX-2 expression with respect to patient age, gender, tumour size, degree of tumour invasiveness, or whether tumours were immunopositive or immunonegative for pituitary hormones, nor have we found any relation between COX-2 expression and recurrence or progression of tumour size.
  
  
  CONCLUSIONS
  COX-2 does not appear to be a predictive factor for recurrence or progression of tumour size. Nevertheless, due to the observed relatively high expression of COX-2 in pituitary adenomas, further studies with COX-2 inhibitors are justified in these tumours.
authors.affiliation: Department of Endocrinology, Jagiellonian University Medical College, Cracow, Poland.
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Sokołowski
authors.forename: Agata
authors.initials: A
authors.lastname: Bałdys-Waligórska
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Trofimiuk
authors.forename: Dariusz
authors.initials: D
authors.lastname: Adamek
authors.forename: Alicja
authors.initials: A
authors.lastname: Hubalewska-Dydejczyk
authors.forename: Filip
authors.initials: F
authors.lastname: Gołkowski
mesh_terms: D049109:Cell Proliferation; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D010907:Pituitary Hormones / Q000378:metabolism; D010911:Pituitary Neoplasms / Q000188:drug therapy / Q000201:enzymology* / Q000473:pathology; D012008:Recurrence
chemical_list: D010907:Pituitary Hormones; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human