Adenoma. 393 



clition known as goitre (struma) ; and sometimes leads to nodular 

 formations which originate from isolated and independently growing 

 cellular foci and are called adenomata, cystadenomata, or adenocar- 

 cinomata, but which are usually accompanied by diffuse enlargement 

 of tlie rest of the parenchyma of the organ. In the same way pro- 

 liferation of the glandular tissue of the ovary and testicle is usually 

 diff\ise, and the distinction detween hypertrophy and true tumor 

 formation is difficult here as well as in the previous example. The 

 cells are usually of an indifferent type and can scarcely be distin- 

 guished from sarcoma cells. In these cases the terms ovarioblastoma 

 or orchidoblastoma are convenient names, according to the organ 

 involved. They may be seen as solid growths or with cyst forma- 

 tion associated, the whole organ involved, the tumors reaching enor- 

 mous size, weighing perhaps ten or fifteen kilograms and often at- 

 taining the dimensions of a human head or even twice that of the 

 full stomach of a horse (in horses, cattle, sheep). 



In the kidneys true adenomata of the uriniferous tubules have 

 never been observed. The tissue proliferations which develop here 

 in the form of tumors, as a rule are of the destructive adenocarcino- 

 matous type and convert the organ into a shapeless, soft material 

 which may break through the capsule. This substance is sometimes 

 as soft as marrow, gray to brownish-red in color, and is made up of 

 large canals lined by cylindrical epithelium. In other cases the 

 growth is combined with sarcoma and^ possibly also with muscle 

 fibres and constitutes an adeno-rhabdomyomatous sarcoma (Johne). 

 [Some of the tumors described as renal adenomata are in real- 

 ity hypcnicphroinata (v. p. 397) ; although the latter growths, which 

 occur in the kidney as their most frequent seat, are ordinarily easily 

 distinguishable. In man there occasionally are seen in sections of 

 kidneys small isolated foci of tubular structure, with the tubules 

 either small and compressed or at places distended into cystic spaces. 

 In the latter papillary proliferations may be found projecting; the 

 w'hole appearance corresponding with the adenoma papilliferum 

 above described. In these cases as a rule the foci are small, perhaps 

 microscopic, and the general picture of the structures suggests their 

 isolation from the rest of the tissue by an inflammatory change. 

 Rarely larger nodules of this character are met, to which we cannot 

 refrain from applying the term adenoma. 



The prognosis of the tumors of the adenomatous group is funda- 

 mentally favorable ; the true adenomata' being entirely free from any 

 tendency to infiltrate or to give rise to metastasis. Such growths 

 are harmful merely from their local influences. The variety above 



