OBJECTIVE: To present this results of a quality-of-life (QOL) assessment performed with the current version of the Lung Cancer Symptom Scale (LCSS) questionnaire in a large single-institutional data set of 650 patients with lung cancer. PATIENTS AND METHODS: The study group included 650 patients with pathologically confirmed primary lung cancer whose conditions were diagnosed and/or treated at the Mayo Clinic in Rochester, Minn, between January 1, 1997, and December 31, 2001. The QOL assessment was performed using the self-administered LCSS questionnaire (version 2) 6 months to 4 years after the diagnosis of lung cancer. RESULTS: The item response rate for all 9 LCSS questions was 94.2% with a minimum of 92.9%. Significant differences in overall QOL by sex (P=.04), Karnofsky scale (P<.001), weight loss (P<.001), disease stage (P<.001), and histology (P=.001) were found, but no significant differences in overall QOL by age (P=.17) or marital status (P=.06) were observed. CONCLUSION: Our data suggest that QOL in patients with lung cancer at varying times after diagnosis highly correlates with baseline prognostic factors (disease stage, histology, Karnofsky scale, weight loss, and sex).