Photons or protons: precision radiotherapy of lung cancer

For localized NSCLC in stages I-III surgical resection continues to be the standard treatment achieving 5-years overall survival rates of 60-70 per cent for stage I cancer. But less than 60 per cent of early-stage non-small cell lung cancer (NSCLC) is being resected because of technical or medical constraints. Conventional radiotherapy alone has been used as the next alternative approach in early stages of NSCLC and is the first choice of treatment for medically inoperable patients and for patients who refuse surgery. Although clinical results are inferior in comparison with results from surgery, dose escalation to the target volume can improve local control probability and overall survival as well. However in conventional radiotherapy maximum doses often are limited by the adverse side effects to the normal lung and heart tissue or to the esophagus. (orig.)