Best Post of August 2016: The utility of TTF-1 immunohistochemistry in the diagnosis of sellar region masses

The next in our "Best of the Month" series is from August 1, 2016:

Posterior pituitary cells (pituicytes) manifest nuclear TTF-1 positivity. Anterior pituitary cells are negative. Three rare neurohypophyseal neoplasms which are derived from pituicytes maintain TTF-1 nuclear positivity: pituicytoma, spindle cell oncocytoma, and granular cell tumor. At times when the neuropathologist is trying to distinguish one of these neoplasms from more common sellar tumors -- such as pituitary adenoma, meningioma, and schwannoma -- TTF-1 can be helpful.

TTF-1 immunohistochemistry in normal neurohypophysis