Pituitary disorders. Drug treatment options.

Abstract

Pituitary diseases are relatively common entities in the general population. They include pituitary adenomas and hypopituitarism. Pituitary tumours can cause symptoms of mass effect and hormonal hypersecretion that can be reversed with surgical resection or debulking of the adenoma, radiotherapy, or medical treatment. Transsphenoidal adenomectomy is the treatment of choice for acromegaly, Cushing's disease, gonadotropin-secreting tumours; and thyrotropin (TSH)-secreting adenomas. Pituitary irradiation and medical therapy are secondary options. Conversely, medical treatment is the primary choice for prolactinomas. Dopamine agonists are very effective in the treatment of prolactin (PRL)-secreting tumours, with rates of control as high as 80 to 90% for microprolactinomas (< 10 mm) and 60 to 75% for macroprolactinomas (> or = 10 mm). Somatostatin analogues have also shown efficacy in patients with acromegaly who have not responded to surgery or in patients with TSH-secreting adenomas who have not improved with surgery and radiotherapy. In patients with Cushing's disease, who are not cured surgically or who relapse after pituitary adenomectomy and irradiation, steroidogenic inhibitors can be an efficient method of controlling the hypercortisolism. Pituitary insufficiency is the partial or complete loss of the anterior hypophyseal function, which is due to hypothalamic or pituitary disease. Although the classic sequence of loss of pituitary secretion is growth hormone (GH), gonadotropins, TSH, and corticotropin (ACTH), the order to begin the replacement therapy of the deficient hormone(s) is cortisol, thyroxine, androgens/estrogens and, if necessary, GH. There are multiple preparations that can be used to achieve clinical and biochemical improvement. In general, the hormone replacement therapy is lifelong.