Isn't this sort of like asking "Why does getting shot kill some but not other?" It depends on which part of the body was shot, and which part of the DNA was damaged.
No. Genetics and nutrition make a big difference here. It is like one person is wearing a bullet proof vest and both were shot in the same place.
The way I read the article was that cancer is caused by deficiencies in the body's repair mechanism. It appears as if some have a more robust mechanism than others, depending on genetics.