Pattern of pituitary adenomas in a West African Hospital

Abstract

Introduction Pituitary adenomas are the third most common intracranial tumours constituting about 15% in most series. Classification of pituitary adenomas is based on immunohistochemical staining properties of the tumours according to the 2007 WHO recommendations. This study was conducted to determine the distribution of the subtypes in a black African population. Materials and methods Fifty-nine archived biopsy samples of cases received over a 13 year period were retrieved. Tissue sections were stained with antibodies for prolactin, growth hormone, ACTH, TSH, FSH and LH. The tumours were classified according to the 2004 WHO classification of pituitary adenomas. Results Females constituted 54% of cases and also had the highest number of cases in all tumour types except gonadotrophs. Null cell adenomas were the most commonly occurring (33.9%) followed by gonadotroph adenomas (32.2%) and mammotrophs were third (18.6%). No thyrotroph adenoma was seen. Three of the adenomas showed plurihormonality with one staining for thyrotroph and corticotroph and two staining for thyrotroph and gonadotroph hormones. Discussion This study showed higher incidence of gonadotroph and null cell adenomas in the population studied. The lower levels of prolactinomas may be explained by medical therapy of patients but could also be due to racial differences.