Using the keywords "nutrition" and "cancer", the Internet spews out thousands of articles. Ignoring the supermarket-checkout-magazine type of article, the others tend to either (a) be debunking various myths or (b) advising to avoid carcinogenic substances or (c) recommending to have a healthy diet in general to avoid conditions (obesity, starving, circulation problems, etc.) that could weaken the immunological system. However, I do not find -- but perhaps I am not looking in the right place -- evidence of specific foods that have been shown to have a direct (instead of the indirect connection via "general health" such as keeping up the immune system) benefit for a human patient who already has cancer (especially lung cancer). Does this exist?