Case report of a "malignant adenoma" (Bailey and Cutler, 1940) of the chromophobe cells of the adenohypophysis with a two year history of intracranial hypertension, left homonymoos hemianopsia, left capsular hemiparesis, hypersomnia, partial amnesia for recent facts, impotency, and hypoacusia, all preceded a year by temporary slight visual disturbances; during the last six months, there were also uncinate seizures and occasional discharge of blood in the sputum. Extensive erosion of the sella túrcica and enlargement of the lateral ventricles were shown in roentgenograms. At necropsy, the tumor was found destroying the walls of the sella, the adjacent parts of body and small wings of the sphenoid, as well as the apex of both petrous bones (Fig. 1). The tumor extended throug the sphenoidal sinus, and projected into the nasopharynx; on the other hand, invading the basal surface of the right cerebral hemisphere (Fig. 2), it destroyed the anterior perfurated area, preoptic region, supraoptic and tuberal portions of the hypothalamus, optic tract, inferior parts of the lentiform nucleus and of the lenticulo-caudate segment of the internal capsule, as well as the uncus and adjacent portion of the hippocampal gyrus. Histologically (Figs. 3 and 4), this tumor differs from the usual adenomas of the chromophobe pituitary cells in its marked cellular polymorphism, greater number of mitoses, and relative irregularity of cellular arrangement.
