The anterior pituitary secretes a number of hormones including:

Tumours arising from such glandular tissue is known as an adenoma. As the pituitary is a highly glandular tissue the most common type of tumour seen is an adenoma, though other cell types are capable of tumourigenesis at this site also. Most pituitary tumours are benign though this may be somewhat of a misnomer. Whilst their malignant potential is negligible they may not be indolent and can cause symptoms. These symptoms may depend on if the adenoma is secretory or not and its potential for local growth.