An Abscopal Response to Radiation and Ipilimumab in a Patient with Metastatic Non-Small Cell Lung Cancer

A posteriori evidence suggests that radiotherapy to a targeted tumor can elicit an immune-mediated abscopal (ab-scopus, away from the target) effect in nontargeted tumors, when combined with an anti-CTL antigen-4 (CTLA-4) monoclonal antibody. Concurrent radiotherapy and CTLA-4 blockade induced immune-mediated abscopal effects in poorly immunogenic preclinical tumor models and patients with metastatic melanoma. However, no such reports exist for patients with metastatic lung adenocarcinoma. We report the first abscopal response in a treatment-refractory lung cancer patient treated with radiotherapy and ipilimumab (a human anti-CTLA-4 monoclonal antibody). A posttreatment increase in tumor-infiltrating cytotoxic lymphocytes, tumor regression, and normalization of tumor markers was observed. One year after treatment with concurrent radiotherapy and ipilimumab, the patient is without evidence of disease. (C) 2013 AACR.