Radiation-induced tumor dormancy reflects an equilibrium between the proliferation and T lymphocyte-mediated death of malignant cells.

Despite its efficacy and widespread use, radiation therapy is often associated with local or distal tumor relapse. We have recently found that CD8 T cells and their cytokines are essential for maintaining irradiated neoplasms under control. In line with this notion, enhancing T-cell functions by means of immune checkpoint inhibitors can tilt the balance toward tumor rejection.