Incidence of pharyngeal hypophysis in neonates a histologic study

The presence of adenohypophysial tissue in the nasopharynx is no longer disputed. This study was performed in 50 neonatal cadavers subjected to medical autopsy within 6 hours of death. The aim was to study the incidence of extrasellar pituitary tissue in the nasopharynx and its various histologic cell types. The transpalatal approach was used to obtain the specimens. The specimens were stained with hematoxylin and eosin and periodic acid-Schiff-orange G for selective demonstration of adenohypophysial cells. Histopathologic evaluation led to the detection of pituitary tissue in 16% of the examined specimens. Selective staining demonstrated a 6% positive incidence of adenohypophysial cells. The pharyngeal hypophysis exists in 2 forms: a typical adenohypophysial collection of cells and an atypical subepithelial cluster. The incidence of hypophysial tissue was higher in the older neonates, perhaps because of hormonal stimulation of the caudal remnant of Rathke's pouch.