I'm all for healthy eating and I believe a healthy diet helps prevent and, in some cases, even cure cancer. However I, and most everyone as far as I can tell, do not agree that cancer is easily cured with a few grocery store items.
Ultimately that really boils down to an arbitrary time definition. Technically speaking we all have cancerous cells present all the time. The arbitrary time cutoff you are using is after critical mass has been reached and severe symptoms felt. By that time, your immune system has been losing a slow battle for years/decades and you had undiagnosed cancer that whole time. That's why they are graded in stages instead of a binary grading system. Stage 4, probably not going to reverse no matter what you try. Precancerous abnormalities, Stage 0.5 because they really don't like calling it cancer, is a sugar coated way of saying cancer that probably won't kill you right away. One could conceivably be cured by changes in lifestyle factors, the other probably not. However, that doesn't negate the sad reality that both are still cancer.
Early nonaggressive cancer can easily be treated using grocery store items. Stage 0.5 cancer is the watch and wait type of cancer but you probably won't hear that you could reverse it at this stage by making some serious life changes. That's because many doctors have become too cynical to believe that you'll actually follow through with the changes necessary for that to happen. Instead, they assume that you'll continue on with your mildly destructive habits until you reach a later stage and then they'll perform chemo or surgery. Same thing happens for pre-diabetes. Why bother teaching the patient something they don't want to learn only to have them ignore your advice. It's much easier to just leave it be and wait until they need medication because that's how 1st world countries work.
Though I'm not a oncologist, I am a doctor with a master's in public health to boot so no clinical slouch. Those that rapidly dismiss lifestyle factors as relevant to health typically don't want to take responsibility for their bad habits. There's an awful lot that the medical community doesn't know and a little that they'd rather not talk about. Take a look at the funded research by the American Heart Association, American Diabetes Association and American Cancer Society and take a look at the distribution of funding between prevention research and management research. American Caner Society is about a 1:2 ratio respectively.
Per the American Cancer Society page.
Obesity, lack of physical activity, and poor diet are major risk factors for cancer – second only to tobacco use. The World Cancer Research Fund estimates that about 20% of all cancers diagnosed in the US are related to body fatness, physical inactivity, excess alcohol consumption, and/or poor nutrition, and thus could be prevented.
Read between the lines could be prevented = early stage cure. Doctors just aren't allowed to call patients out to their faces because yelp reviews actually matter to hospital administrators now.
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