With the development of science ,the Cancer theories have been changed .
the scientists proposed different historical theories over the years trying to explain cancer and its causes ,some of these theories were proven wrong and some grew more complex .These theories are :
-Humoral Theory
-Lymph Theory.
- Blastema Theory.
- Chronic Irritation Theory. -Trauma Theory.
- Parasite Theory.
which will be dis.cussed below :
*Humoral theory :
Humoral theory can also be called the theory of four different humorism. This theory was systemized by the Greek physician Hippocrates, so it could be named Hippocrates theory.
In this theory he described