Clinically nonfunctioning pituitary tumors

Abstract NFPAs are clinically silent tumors that develop from different pituitary lineages. Their classification landscape has changed with the recognition that even in the absence of evidence of hormone production based on immunohistochemistry, they can be assigned to specific lineages based on staining for transcription factors. Early evidence suggests that the clinical behavior of transcription factor positive/hormone negative tumors is similar to that of transcription factor positive/hormone positive tumors. Whether these findings, if confirmed, will have significant implications on the clinical management of NFPA remains to be established. There is consensus regarding surgery as the first-line treatment of these often large tumors, which present with clinical signs and symptoms of mass effect. However, the optimal postsurgical management is still a matter of debate. The selection of tumors that need adjuvant treatment, as well as the timing and type of medical and/or radiation therapy, remains to be established.