In 2017, Oswald was diagnosed with stage 4 non-small cell lung cancer. His doctor told him that a newly approved PD-1 checkpoint immunotherapy was his best treatment option. He received the first infusion in February 2017 during a three-month hospital stay. Scans showed that the cancer shrank dramatically after his second infusion. He was able to put weight back on, resume work at his nonprofit, and get back to the gym. Oswald is now cancer-free and receives immunotherapy treatment every nine weeks. He is passionate about spreading the word about cancer immunotherapy research and treatment as a CRI ImmunoAdvocate.