Abstract
The body of evidence that is supporting the role of T cells in human tumor control is substantial and it is now beyond doubt that T cells can be crucial in the clinical response to cancer immunotherapies such as adoptive T cell therapy and checkpoint blockade. This has been proven in particular for melanoma and non-small cell lung cancer. Strikingly, while clinical experience with these therapies is extensive, what these T cells detect on the tumors remains largely unknown. An extensive effort has been put into the characterization of tumor antigens and based on the recent successes of immunotherapies Cancer/Germline, mutated and viral antigens appear rather promising targets for tumor control. Furthermore, it is becoming evident that the most potent antigen in tumor control is highly dependent on the type of malignancy and may also vary even within malignancies.