Note that in surgical series of pituitary microadenomas considered as prolactinomas in the preoperative period, approximately 17% did not confirm the diagnosis of prolactinomas by immunohistochemistry, showing that they were non-functioning lesions erroneously diagnosed as prolactinomas due to stalk disconnection.(31) These data reinforce the importance of monitoring tumor size after DA prescription for later differential diagnosis between prolactinomas or non-functioning lesions of the pituitary region that induced an increase in serum PRL levels due to disconnection of the pituitary stalk. This evidence concerns the gene PRL and neoplasm.