The real question would be: How long did it have cancer and did it pick up any diseases? Chance would be good that the over-stressed immune system might become vulnerable to other not-so-good-for-you diseases.
The cancer meat itself, provided it is disease free, should not be a worry. Cancer is caused by mutations in DNA, which you freely break down into its component nucleotides for your own use (either for energy or DNA synthesis). The cancerous cells are simply fast and out of control growing cells. They may, depending on the cancer, not be any different from normal cells.
But I still would be hesitent to eat it, just because.