How and why did the proliferation of cancer come about over the last century?

Cancer does not come out of the blue. It develops as a result of underlying conditions of distress of the organism, which is really the only "dis-ease" there is. Cancer can be prevented, perhaps even stopped, by reducing the factors that cause distress.

Yeswise Education Service holistic learning modules: health, poisons, survival, the control system, holistic philosophy: https://yeswise.com

~ program archives, notes, resources: https://awaremore.com/Programs

~ survival preparedness: https://survivethechanges.com

~ natural health items: https://reallywell.com

~ full article on cancer: https://NaturalHealthPortal.com/cancer.htm