We believe that you have to go back 4 billion years to when life first originated on the Earth to discover how cancer originated. When you do so, you discover many fascinating connections between the origin of life and cancer. The main part of our theory relies on the mycoplasma bacteria (please search on Wikipedia or go to our website, originofcancer.com for more information). The mycoplasma bacteria is responsible for many different kinds of cancer, according to Wikipedia. We feel that this and many other clues support our new theory on where cancer comes from.