The Tox Tutor section on cancer has a good overview of the process, why cancer is a dreaded disease and many items you will need to understand and explain cancer health hazards. It also says: Carcinogenesis is referred to as a multi-step, multi-factorial genetic disease. All known tumors are composed of cells with genetic alterations that make them perform differently from their progenitor (parent) cells. The carcinogenesis process is very complex and unpredictable consisting of several phases and involving multiple genetic events (mutations) that take place over a very long period of time (at least 10 years for most types of cancer). http://sis.nlm.nih.gov/enviro/toxtutor/Tox3/a33.htm
[Here is the revised tox tutor with some different pictures https://toxtutor.nlm.nih.gov/14-003.html
Here are the tables that estimate the percentage contribution of various "causal factors"
These seem correct, but they neglect the most significant cause of cancer deaths
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