Quality-of-life trials in lung cancer: past achievements and future challenges

Quality of life (QOL) has become recognized as an increasingly important endpoint in clinical oncology trials of lung cancer. This article first reviews the fundamental issues underlying QOL in clinical oncology trials, with special attention to instruments that have been validated to study lung cancer patients. QOL studies in patients with metastatic lung cancer involving chemotherapy are reviewed next, followed by QOL studies in lung cancer patients receiving radiation for palliation or as part as definitive treatment for locally advanced disease. Prior achievements are highlighted, such as the benefit of chemotherapy or radiation in terms of improving pain and dyspnea in the setting of metastatic non-small cell lung cancer. Ongoing challenges also are noted, such as the critical issue related to missing data. Future studies should focus on incorporating QOL into phase III trials with clear hypotheses that can ultimately lead to clinically meaningful interventions.