798 J. P. SIMONDS 



literature as malignant struma or malignant adenoma might more cor- 

 rectly be classified as carcinomas. 



Carcmomatous growths of the hypophysis may reach considerable 

 size, the largest of which I found record measured 6 by 4 by 7 cm. They 

 invade the capsule of the gland; become adherent to the adjacent struc- 

 tures; erode bone and grow into the openings thus made; and their sur- 

 faces are irregular and nodular. 



The histologic structure of a carcinoma of the hypophysis is atypical. 

 The cells are no longer arranged in the characteristic cords, or groups, or 

 acini; but are more closely and irregularly packed together with scant 

 stroma between the cell masses. The cells are chiefly chromophobic in 

 type, but by the employment of special stains, granules can be demon- 

 strated in some of them, thus indicating the epithelial origin of the tumor. 

 Those cells which surround the blood vessels are frequently cuboidal or 

 cylindrical and are placed radially about the vessel, an arrangement which 

 led Moskalew to apply the name "epithelioma telangiectoides" to a car- 

 cinomatous growth of the hypophysis, The histologic structure may vary 

 in different parts of the tumor mass, as noted by Strada, Hippel, and 

 Bibbert, Often that portion of the tumor which breaks through the dura 

 mater and grows diffusely is more atypical in structure than the intrasellar 

 part. An explanation of this may be that the portion which remains in the 

 sell a turcica represents the remains of the normal portion of the gland 

 which has become more or less invaded by the carcinomatous cells. For it is 

 no more likely that all of the cells of the anterior lobe of the hypophysis 

 simultaneously become cancerous than that all of the cells of the breast ac- 

 quire malignant characteristics at the same time. So small an organ as the 

 hypophysis can quickly become thoroughly infiltrated with the new growth. 



In the most atypical forms of carcinoma of the hypophysis, the tumor 

 may lose all distinguishing characteristics of hypophyseal structure. The 

 cells become so completely dedifferentiated that they may resemble small 

 round cells, or even, perhaps as a result of mutual pressure, spindle cells. 

 It is only by the finding of a few granules in occasional cells in specially 

 stained preparations that these tumors can be differentiated from sarcomas 

 and correctly classified. 



Sarcoma. The occurrence of sarcoma of the hypophysis is possible, 

 but it appears probable that the majority of those cases reported in the 

 literature as sarcomas were, in reality, the most atypical and most malig- 

 nant form of carcinoma. Until cases are reported in which the diagnosis 

 is proven beyond question by the use of special granule stains, there is 

 little to be learned from a study of the cases recorded in the literature as 

 "sarcoma of the hypophysis," In the 38 cases so diagnosed which I 

 have collected almost every type of sarcoma is included except the giant 

 cell type. Round cell sarcoma was the diagnosis which appeared with the 

 greatest frequency. 



