Tumors. 349 



Myxomata. 



A myxoma, a mucous connective tissue tumor, is a neoplasm 

 which consists either entirely or in part of gelatinous embryonic 

 connective tissue ; and therefore its tissue closely simulates the 

 Wharton's jelly of the umbilical cord in consistence, transparency 

 and texture. It is characterized microscopically by an intercel- 

 lular substance rich in mucin, in which are sparsely scattered 

 cells of spindle and highly branched stellate forms with long 







^ 



•^^ 



^:j 



\ 



hi 



^% 



S. 



Fig. 91. 

 Myxoma. 



slender prolongations; while here and there are to be seen blood 

 vessels and a small amount of fil^rillar connective tissue. In 

 fresh material the mucinous substance may be precipitated by 

 the addition of acetic acid. Often only individual portions of 

 the tumor are conspicuously myxomatous, the remainder being 

 made up of fat tissue or dense fibrous tissue (myxolipoma, myxo- 

 Hhroma) ; and many luxuriantly growing types show features 

 of transition to sarcoma and mixed tumors (myxosarcomata^. 

 Occasionally fibromata and lipomata of pedunculated shape. 



