<prompt> Which of the following is true about pituitary adenomaa Accounts for 10 of brain tumorsb Erodes the sellar and extends into surrounding areac Prolactinoma is least commond It is differentiated by reticulin stainacdabdabcab  <response>: Pituitary adenomas constitute approximate 10 of all primary intracranial neoplasms and about 13 to 12 of all suprasellarjuxtasellar massesPituitary adenomas are classified on the basis of hormones produced by the neoplastic cells detected by immunohistochemical stains.Most common pituitary adenomas are prolactinomas.Pituitary adenomas can be differentiated from hyperplasia by reticulin stain Absence of reticulin network is seen in adenomaPituitary adenomas are sellar lesions but larger adenomas can extend through the diaphragm sella into the suprasellar region and compress the optic chiasm causing visual field abnormalities and other cranial nerves. Large adenomas can also erode the sellar turcica and extend into surrounding region ka invasive adenomasMore about Pituitary adenomas It is the most common cause of hyperpituitarism.Pituitary adenomas can be- functional i.e. associated with hormone excess and their clinical manifestations or- silent i.e. without clinical symptoms of hormone excess. May or may not produce hormoneProlactinomas are the most common adenomasSome pituitary adenomas can secrete two hormones - Growth hormone and prolactin being the most common combinationRarely adenomas are plurihormonalAge : usually found in adultsGenderProlactinomas have 4-5 : 1 femalemale ratioGH secreting adenomas have 2:1 male predominance.Clinical signs symptoms - occur due to hormone excess or mass effect visual field disturbances, elevated intracranial pressure or occasionally hypopitutarism - dt silent adenomas compressing normal pituitaryAcute hemorrhage into an adenoma causes rapid enlargement of mass and sudden clinical deterioration ka pituitary apoplexy.Prolactinomas have a propensity to undergo dystrophic calcification, ranging from isolated psammoma bodies to extensive calcification of entire tumor mass ka pituitary stone 