[Cancerous toxin is the key pathogenic factor of malignant tumor].

The definition of cancerous toxin and the relationships between cancerous toxin and other factors including the etiopathogenesis, pathogenesis and treatment of malignant tumor were discussed in this paper. The author suggests that the cancerous toxin is engendered by the disequilibrium of human body, which is the foundation of tumorigenesis. Cancerous toxin is the main pathogenic factor or one of the main pathogenic factors during the development of malignant tumor, hence it is also the key point for understanding and treating malignant tumor.