Pituitary Choristoma: A Survey of Thirty Cases

FROM time to time in post-mortem reports, a small tumour of the posterior pituitary stalk, called a choristoma, is an incidental finding. Looking through the reports of the Pathology Department of Queen's University, it was possible to find thirty cases of choristoma over the past twenty years. The tumour was first noticed by Boyce and Beadle in 1893, but was called "Choristoma" by Sternberg in 1921. It is also called a granular cell myoblastoma. Histologically, it is a collection of large granular cells, with peripheral nuclei and is now considered by most investigators to be of ectodermal neurogenic origin (Sternberg, 1921; Priesel, 1922; Simonds and Brandes, 1925). A small tumour about 1 mm. in diameter and often multiple, it is generally regarded as being benign, although malignant changes are described (Ross, Millar and Foote, 1952). Pituitary choristomata have no known function. MATERIAL AND METHODS. Tabulating the cause of death in the thirty cases of choristoma