Radiology and Oncology

Tumour immunology & immunotherapy

Tumour immunology describes the interaction between cells of the immune system with tumour cells. Understanding these interactions is important for the development of new therapies for cancer treatment. The existence of specific anti-tumor immunity implies that tumors must express antigens that are recognized as foreign by the host. The earliest classification of tumor antigens was based on their patterns of expression. Antigens that are expressed on tumor cells but not on normal cells are called tumor-specific antigens; some of these antigens are unique to individual tumors, whereas others are shared among tumors of the same type

1. Products of Mutated Genes
2. Abnormally Expressed but Unmutated Cellular Proteins
3. Antigens of Oncogenic Viruses
4. Oncofetal Antigens
5. Altered Glycolipid and Glycoprotein Antigens
6. Tissue-Specific Differentiation Antigens

Immune Responses to Tumors

1. T Lymphocytes
2. Antibody
3. Natural Killer Cell
4. Macrophages

Immunotherapy for Tumors

The main reason for interest in an immunologic approach is that most current therapies for cancer rely on drugs that kill dividing cells or block cell division, and these treatments have harmful effects on normal proliferating cells. As a result, the treatment of cancers causes significant morbidity and mortality. Immune responses to tumors may be specific for tumor antigens and will not injure most of the normal cells. Therefore, immunotherapy has the potential of being the most tumor-specific treatment that can be devised.