The term “antitumor immunity” refers to innate and adaptive immune responses that lead to tumor control.

An apparent paradox exists between the evidence for spontaneous systemic T cell-mediated anti-tumor immune responses in cancer patients, observed particularly in their bone marrow, and local tumor growth in the periphery. This phenomenon, known as “concomitant immunity” suggests that the local tumor and it's tumor microenvironment (TME) prevent systemic antitumor immunity to become effective.