Tumor-specific antigens and the homograft reaction

Abstract

True tumor antigenicity has now been demonstrated in several different systems in experimental animals. The immunity produced is similar to that found in the homograft reaction, and much of the information related to homografts has applicability to tumor-immunity systems. Extreme care is necessary in experimental work to distinguish between the two types of immunity. Thus far the tumor antigens appear to be peculiar to the particular tumor or type of tumor; there is no evidence, in the work cited, of a universal cancer antigen. The animal findings probably have human counterparts and tumor antigenicity may help explain some of the paradoxical behavior of human neoplasms. The possibility of antitumor immune responses in human beings might well be considered when therapies which might damage the immune response are contemplated. The probable existence of tumor-specific antigens in human neoplasms may also help explain the unexpectedly low incidence of metastases in some instances of human cancer in which numerous circulating tumor cells are found. The recent work on specific-tumor antigens in mouse cancers appears to justify cautious optimism concerning the ultimate role of immunologic studies in the control of the human disease.