"Cancer" is when this system goes awry, and the cells in a tissue replicate faster than is healthy, and/or fail to die when they should.
Why does this happen? WE ALREADY KNOW WHY. We don't need billions more dollars to feed the Medical Sector.
Pollution and malnutrition are the two main causes of "cancer".
We can prevent and cure most cases of cancer with what we know right now, without any products or services of the Medical Biz (tradename: "healthcare").
A few examples:
Vitamin D3
Higher Vitamin D Intake Needed To Reduce Cancer Risk
http://ucsdnews.ucsd.edu/archive/newsrel/health/02-22VitamanD.asp
Of course, the American Cancer Society opposes it:
New research shows vitamin D slashes risk of cancers by 77 percent; cancer industry refuses to support cancer prevention
http://www.naturalnews.com/021892_vitamin_D_American_Cancer_Society.html#ixzz3xATJhlmR
Vitamin C
The Vitamin C Foundation
https://www.vitamincfoundation.org/wiki/doku.php?id=cancer&s[]=cancer
Abram Hoffer via Doctor Yourself
http://www.doctoryourself.com/hoffer_cancer_2.html
Speaking of low-carb
Is there a role for carbohydrate restriction in the treatment and prevention of cancer?
Selenium
Life Extension Foundation
Selenium: What Forms Protect Against Cancer?
https://www.lifeextension.com/magazine/2012/ss/selenium-protect-against-cancer/page-01Fasting
Mark Sisson of Mark's Daily Apple
http://www.marksdailyapple.com/fasting-cancer/#axzz3xAX7QRaO
also,
"The researchers say fasting “flips a regenerative switch” that prompts stem cells to create white blood cells, essentially restoring the immune system."
http://news.nationalpost.com/health/fasting-for-three-days-renews-entire-immune-system-protects-cancer-patients-remarkable-new-study-find
Pollution
Air Pollution's Impact on Cancer Is "Grossly Underestimated"
http://www.scientificamerican.com/article/air-pollution-s-impact-on-cancer-is-grossly-underestimated/