Primary papillary epithelial tumor of the sella: a case report of an emerging tumor type.

Primary papillary epithelial tumor of the sella (PPETS) is a newly described tumor entity with prototypical location in the sella. Only two case series with ten cases have been described so far. These tumours have a typical papillary architecture with bland nuclear features, TTF-1 immunopositivity and low MIB-1-labelling index. Many of these tumours were previously assigned under the category of 'ectopic choroid plexus papilloma'. PPETS expands the group of TTF-1 positive tumours of the central nervous system. Histomorphology plays an essential role in making this diagnosis. We report a case of 44-year-old female with a sellar mass lesion, who presented with progressive loss of vision and diagnosed as primary papillary epithelial tumor.