Endocrine Abstracts

In many neoplasms, excessive angiogenesis is prognostic factor, independent from proliferation. Previous studies confirmed correlation between cyclooxygenase-2 (COX-2) expression and micro-vascularization density in pituitary tumors. Moreover, nonsteroidal anti-inflammatory drugs have strong inhibiting effect on COX-2 expression and possible anti-tumor activity.

Aim: To assess COX-2 expression in pituitary adenomas, its relation to adenoma type as well as to determine the role of COX-2 as prognostic factor of patients with pituitary tumors.

Methods: The retrospective study included 60 patients aged 18–85 years, after pituitary tumor surgery. COX-2 expression, determined by immunohistochemical methods, was analyzed in relation to the radiological and histopathological tumor features, clinical symptoms caused by adenomas and postperative course of disease.

Results: COX-2 expression was present in 87% of adenomas with median index of 57.5%. The highest COX-2 indices characterized hormonally inactive adenomas and gonadotropinomas, the lowest - prolactinomas. There were no statistically significant differences in COX-2 expression regardless patients age and sex, tumor size, its invasiveness, visual impairment, recurrence/progression during postoperative course, the need to reoperate or irradiate.

Conclusions: COX-2 expression is of little prognostic value in patients with pituitary adenomas. However high COX-2 expression in pituitary adenomas, especially those hormonally inactive, makes it possible target for treatment of those tumors.