The majority of NFPAs (73%) belong to the SF1 lineage, 16% of them are silent corticotroph adenomas (SCAs) of the TPIT cell lineage, while PIT1 cell lineage silent adenomas account for 9% of NFPA cases, with a rare occurrence of truly null cell tumors (negatively stained tumors of TFs and pituitary hormones) (4, 7). This evidence concerns the gene TBX19 and adenoma.