This document discusses a cancer cell mutation identity theory. It proposes that cancer cells have a binary identity with both mutated and normal DNA. The mutations are proposed to originate from outside the cell, with macrophages sending DNA sequences from different immune cells during chronic inflammation. This introduces thousands to millions of mutations from carcinogens, mutagens, mitochondrial breakdown and chronic inflammation. As a result, the cancer cell identity is comprised of more non-self mutated DNA than original self DNA, giving them different antigenic positions.