Many lost due to cancer of a loved one, or just heard about the horrors of the disease. They therefore believe that cancer - it is a strong and powerful disease that can strike the human body and completely destroy it. In fact, the science of cell - cell biology - the opposite. Cancer cell by nature weak and poorly organized.Cancer begins with a cell containing an incorrect genetic information that makes her unable to fulfill its function. This cell could get the wrong information because of harmful chemical exposure, other external reasons, or simply because in the process of continuous reproduction of billions of cells in the body from time to time mistakes. If this cell begins to reproduce other cells with the same genetic structure violation, tumors, consisting of a large mass of abnormal cells. Usually protective (immune) system of the body recognizes these cells, destroys them, or at least limit their action so that they could spread. Now "everyone knows" that cancer is caused by carcinogens, genetic predisposition, radiation, or possibly malnutrition. In fact, none of these factors alone can not serve as a sufficient explanation of why one person gets cancer and another - no.
Many consider, that if wild animal since the childhood to bring up among people, not to feed with crude meat, etc., he will grow quite house.
On the other hand, there are many cases when the most plush and manual lions, bears and so on rushed on the owners, or on their children, and it came to an end very badly.
Personally my opinion - an animal as the person everyone with the character, is normal, and is malicious, and the mood happens everyone. Besides, native elements of an animal - the nature. Therefore it is necessary to try to find common language with animals on the nature, instead of to hold them in bondage.
Still, on reflexion: Though somebody, sometime has tamed a cat? Or, in another way: Is though one cat who never has scratched nobody, or has not bitten? However, on these scratches people of the big attention do not turn. The same blow by a paw from larger cat's will leave much more serious damages, and a sting and at all can end badly for the person.
Your relation to manual lions and crocodiles.