SAECOMATA. 71 



Myomata are generally described as being tumours composed 

 of unstriped muscle fibre, and may be associated with any of the 

 organs in which involuntary muscle may be present. They are 

 peculiarly liable to occur in connection with the uterus, and may 

 in these situations be mixed with a considerable quantity of 

 fibromatous tissue. In connection with the alimentary tract 

 myomata have been most frequently seen in the oesophagus, the 

 stomach and the duodenum in other words, in the proximal 

 portions of the tract. 



Myelomata, or red marrow tumours. 



These tumours are composed of tissue very similar to the 

 red marrow of growing bone, and were formerly spoken of as 

 myeloid sarcomata. They are nearly always found at the 

 cancellous ends of long bones, and most frequently at that end 

 which is the epiphysis from which the bone chiefly grows in 

 length, as for instance the lower end of the femur, the upper 

 end of the tibia, and the lower end of the radius. Another 

 common place for a myeloma to originate is in the cancellous 

 tissue of the mandible, the growth expanding the bone so as to 

 produce the characteristic thinning of its compact outer layer. 



Sarcomata. This is the only truly malignant connective- 

 tissue tumour. It may occur in any mesoblastic tissue, and 

 therefore in almost every organ of the body. While this is true, 

 the growths are found much more commonly in certain regions 

 than in others ; periosteum, fascia and subcutaneous tissue 

 are peculiarly liable to be the seat of round- or spindle-celled 

 sarcomata. 



Again, all composite glands, such as the kidney, testis, parotid, 

 etc., are prone to the incidence of sarcomata. 



The pigmented form of the neoplasm melano-sarcoma 

 arises in the skin, in the uveal tract, and sometimes in mucous 

 membranes. 



The spread of sarcomata is governed to a great extent by 

 anatomical considerations. All tumours of this nature are 

 extremely vascular, and the blood vessels connected with them 

 are ever prone to carry the elements of the growth to distant 



