I’ve heard something to that effect about cancers being caused initially by viruses. Similar to what researchers have discovered about ulcers. Considering the amount of $ that drug companies, insurance companies, politicians and the medical industry in general are making off of the ongoing “war” against cancer, although horrifying, it would not be surprising to know that they’ve hidden the truth.
I don’t think they are hiding anything that is already known. I think it’s more a matter of getting enough funding for research to prove it. Similar to the difficulty in getting research for treatments that can’t be patented or for orphan diseases with limited marketability. Countries with socialized medicine would probably want to use any currently known treatments that reduced their total spend.