What are the causes of pituitary acromegaly?

Disordered Somatotroph Cell Function (activated oncogene for somatotroph cells, stimulate GHRH and GHS, maybe germline mutation (FIPA- mutation in supressor)) Disordered GHRH Secretion or Action Ectopic Pituitary Adenomas (GH releasing from remnants of sphenoid sinus, petrous bone, nasopharynx, very rarely carcinoma)