CHEMOTHERAPY IN MALIGNANT DISEASE 889 



more marked affinity for tumor cells, and the whole subject is probably 

 just at the threshold of further discoveries that may be applied with 

 great benefit to the treatment of human malignant disease. In a recent 

 review of the whole subject Weil 1 has concluded that when the results 

 are viewed and studied in a critical manner, it is apparent that none of the 

 various methods of treatment advocated so far can lay claim to thera- 

 peutic effectiveness. According to Weil, the demonstrable reduction 

 in the size of a tumor, of a kind not to be attributed to the natural 

 processes of evolution of that tumor or of its associated lesions, is the 

 one essential feature of effective therapeutic intervention. 

 1 Jour. Amer. Med. Assoc., 1915, 64, 1283. 



