Risk factors.

I was reading a little article on judging your risk of/genetic predisposition towards breast cancer, involving how many blood relatives have had it, or have had "related" cancers, etc.

What I want to know is, can there be a genetic predisposition towards cancer? That is, not just one particular form, but towards cancer in general? And, even if not, outside of breast and ovarian cancers being related, are other forms of cancer that are related to one another? Which?

My father's sister died at 53 of pancreatic cancer. Their father died of (admittedly environmentally related) leukemia, and their mother of brain cancer. Her brother died a handful of years ago--I think that was cancer, too, but I'm not certain of it, or of which kind, if so--and their sister had tumors (non-malignant) in her breasts. So did my mother's mother. And another blood relative (either mother's father or mother's mother's father, can't remember which) died of cancer, too, on that side. Kidneys, I think, but maybe it was liver.

My father, like his sister, died when he was 53 (of everything, apparently), but sometimes, in full blown paranoid mode, I wonder if he didn't have cancer, too, and just didn't tell us. He was very proud, he didn't talk about things that were wrong. He saw plenty of doctors for all his various problems, got sicker and more beat up as time went on, and would come home sometimes with his head shaved completely bald, and have his hair grow back softer and whiter than it had been, before. Maybe he just decided to do that? And maybe it just coincidentally coincided with his follicles giving out in their melanin-producing capacity? But shaving it off would certainly cover up hair falling out from therapy, too.

But even not relying on that, there's still a pretty heavy dose coming in from his side. And that's not getting anywhere near the heart attacks and strokes, depression, alcoholism, and other potentially genetically pre-disposing trouble on either side. (In case I haven't mentioned, I'm not having children. The fact that they'd be doomed is only a small part of that, but it bears mention.)

So. What I wonder is, do all of these disparate cases of different kinds of cancer amount to a general predisposition for it? Can there be that?

Just something I think about. Y'know. Sometimes.