2()C> EPITHELIAL CARCIXOMATA. 



morpliosis beginning in tlie axis of the protrusions. The 

 phenomena in question consist mainly in fatty degeneration 

 of the epithelial cells, loading to the formation of a number of 

 atheromatous abscesses. These are originally distinct^ but they 

 gradually coalesce to form a single cavity extending through the 

 entire length of the protrusion. Such cavities may be recognised 

 on the surface of the epithelioma even with the naked eye as 

 yellowish-white, comedo-like points. They ultimately burst ; 

 the excavated protrusions open up and discharge their contents 

 on the surface. The tumour thereupon collapses, and the ulcera- 

 tion, the discharge of pus and atheromatous pulp, to which allu- 

 sion has been already made, begins. 



Epithelioma does not belong to the most malignant group of 

 morbid growths. At least cases of radical extirpation (?.^. with 

 no attempt to spare surrounding parts) not followed l)y any 

 return of the disease, have been vouched for by responsible 

 observers. Such cases, indeed, are by no means common. 

 Within a year from the operation, the cicatrix generally be- 

 comes the seat of a new growth of analogous character. On the 

 other hand, metastasis proper is comparatively rare. The nearest 

 lymphatic glands are the first to be affected ; the internal organs 

 not being involved until the primary mischief has attained 

 dimensions so colossal, that the trifling metastatic lesions are 

 unimportant in comparison. The metastasis is probably due in 

 all cases to the immigration of young epithelial cells, which 

 cause an '' epithelial infection " of the autochthonous elements of 

 the conjoint vascular and connective-tissue system at the point 

 where they settle. 



§ 171. Columnar Epithelioma. Until very lately, obser- 

 vers could not agree whether to regard the crypts of Lieherkuhn 

 in the digestive tract as genuine tubular glands, or merely 

 as crypts, i.e. csecal inflexions of the surface solely designed to 

 increase its superficial area. The difficulty was mainly histo- 

 logical ; for it was shown that these so-called glands were lined 

 throughout with columnar epithelium of exactly the same kind 

 as that which clothed the free surface itself and its papilln?. 

 The results of pathological histology are not in any way adapted 

 to allay the scruples thus aroused ; for the only affection from which 

 we might expect to gain some conclusive evidence on this sub- 

 ject, sc. columnar epithelioma of the digestive tract, involves the 



