Cancer. 



407 



tubular arraugement of the cells, and the simple (one layer) lining 

 of these tubes may so well preserve the gland pattern that the name 

 adcno-carciiioiiia has been applied to these and to the tubule-forming 

 cylindrical cell cancers. The resemblance to the original gland may 

 be so great that not merely the morphology of the most of the tumor 

 cells remains unchanged, hut even the production of secretory sub- 

 stances in the tumor tissue is distinctly analogous. Thus hepatic 

 cancers have epithelial cells of precisely the same type as the polygo- 









PI 



S~4^^ 





^^^^' v^^-^^ 



Fig. 124. 



Microscopic section (if adenocarcincma of icidney of horse. 



nal hepatic cells, arranged in anastomosing trabecular columns, with 

 capillaries and scanty connective tissue extending between them ; 

 and these epithelial cells secrete bile, the tumor sometimes being 

 stained an intense yellow or green color from the latter. Thyroid 

 cancers, made up of low. cubical, thyroid epithelial cells and a vas- 

 cular stroma, show as a rule a practical duplication of the structure 

 of the thyroid gland in the production of colloid material and in 

 the alveolar distension of their epithelial ofifshoots. Cancers of the 

 intestinal glands repeat the tubular invaginations of the Lieber- 



