Pet/CT scans show a patient with metastatic cancer. The left image has a symbol representing radiation added and the right has a symbol representing injection added. Combining radiation and local tumor immunotherapy may produce an anticancer immune response that kills the radiated and injected tumor and also the distant metastases. Credit: NIHCD for the scan. Adapted by Nancy R. Gough BioSerendipity with the addition of the radiation on the left and the syringe on the right.