Tumor immunology is the study of the antigens associated with tumors, the immune response to tumors, the tumor’s effect on the host’s immune status, and the use of the immune system to help eradicate the tumor. Tumors, therefore, are composed of cells that possess many of the attributes of the normal cells from which they arose but have accelerated or dysregulated growth. In this video, we will discuss the difference of benign and malignant tumors, the different types of antigens found in tumors, the Immunity of the body against tumors and the different tumor markers used for Laboratory testing.