302 



PATHOLOGY OF NUTRITION. 



Carcinoma simplex, or spheroidal-celled cancer, arises in 

 glands with spheroidal epithelium, as, for example, the mam- 

 msa. The acinous or glandular arrangement of the tissue 

 from which it grows is soon obscured and replaced by the 

 perfect alveolar structure typical of cancer. In the earliest 

 stage of its growth there would be simply noted at a given 

 point within an acinus a proliferation and piling up of the 

 epithelial cells. Soon they break through the basement-mem- 

 brane and infiltrate the surrounding connective tissue. The 

 cells are generally spheroidal unless altered by mutual press- 

 ure. According to the density of the connective-tissue stroma, 

 two varieties are distinguished, the scirrhous and encephaloid. 



In the scirrhous variety the epithelial element is relatively 

 small ; the tumor is hard and grows slowly (Fig. 131). In 



FIG. 131. 



Scirrhous of mamma. X 100 (Ziegler). 



encephaloid the stroraa is scanty, the tumor of soft consis- 

 tency and rapid growth (Fig. 132). 



Cylindrical-celled cancer, or adenocardnoma f arises from 

 surfaces covered with cylindrical epithelium, as from the 

 glands of the gastro-intestinal tract. Especially in the early 



