Sarcoma. 367 



beginning, and their proliferation and that of the mature types of cells 

 have from the first developed side by side, or whether a simple tumor 

 originally existed and later assumed a typical growth from changes in the 

 cellular proliferate. In the former case the combined types of tissue may 

 lie indicated l)y the use of two nouns (as fibro-sarcoma) ; in the latter 

 .by the adjective prefix "sarcomatous" [the change into sarcomatous type 

 may be expressed]. In the course of clinical observations, where the 

 succession of various features is recognizable, such distinctions may be occa- 

 sionally made ; but in purely anatomical considerations they cannot be made. 



Fig. 103. 



Spindle cell sarcoma, from periosteal origin : a, transverse section of hnnrlle of 

 splndlo cells ; b, capillary blood vessel. 



The round cell sarcoma (sarcoma globocclliihirc) consists either 

 of cells of the appearance of lymphocyteSj small round elements with 

 narrow cytoplasm and granttlar nucleus (small cell sarcoma), or of 

 large round and polymorphous cells (large cell sarcoma), closely 

 packed together and with such a small amount of fibrillar intercellu- 

 lar substance that the cells are but loosely attached. The tumor 

 has a very soft consistence and is of a grayish to a grayish-red 

 color. When the supportive tissue enclosing the round cells is 

 arranged in a reticular manner, forming a fine fibrillar meshw^ork, 

 and the tumor has originated from one of the lymphatic structures 



