MALIGNANCY 51 



tissues concerned. When their balance is upset, one pro- 

 liferates abnormally. Anything that throws the organism 

 out of gear is a possible factor of malignancy, and that is the 

 reason why, with the increase of wealth, a new and highly 

 varied environment, which tends to produce variation, 

 makes for the increase of such disease. 



If the value of a theory depends on the aid it gives in 

 explanation, the one here advocated certainly helps to 

 make it clearer why some forms of malignancy are more 

 deadly and liable to metastasis than others. So far there 

 has been no real explanation of the fact that the forms of 

 it which deviate most widely from the tissue of origin are 

 most rapid and destructive. It has remained an observa- 

 tion, and to say this extreme aberrancy from type 

 renders it more deadly is only to repeat in another 

 form what has been said before. But if it is under- 

 stood that the immediate and total somatic environ- 

 ment determine cell character, it is obvious that extreme 

 aberrancy implies that the determining tissues generally 

 are weakened to an extreme degree, and that any 

 cancer growth or embolus will nowhere meet with much 

 resistance. That environment has definite results is well 

 known. In speaking of the relatively more deadly femoral 

 sarcoma, as compared with a similar tumour in the tibia, 

 Bland-Sutton says: "This would appear to indicate that 

 the two tumours, though structurally alike, really have 

 different causes, yet these are facts which lead us to 

 suppose that variations in tissue actually constitute a 

 different environment . " He adds that echinococcus disease 

 is the only condition which supports this view. Yet surely 

 in studying all diseases we are compelled to come to the 

 conclusion that different reactions, in different patients, with 

 the same disorder, can only be due to their bodies consti- 



