Study objectives: Radiotherapy is considered to be the standard treatment for patients with stage I or II non-small lung cancer who refuse surgery or who are not surgical candidates because of significant comorbidities. To determine whether radiotherapy benefits these patients, we compared the survival of those treated with radiation alone to those left untreated.
Methods: Using the Surveillance, Epidemiology, and End Results registry, we identified all patients in whom histologically confirmed, stage I and II non-small cell lung cancer had been diagnosed between 1988 and 2001. Among these patients, 4,357 did not undergo surgical resection. Kaplan-Meier survival curves were compared among patients who received and who did not receive radiation therapy. We used Cox regression analysis to evaluate the effect of radiation on survival after adjusting for potential confounders.
Results: The survival of patients with lung cancer who did not undergo resection and had been treated with radiation therapy was significantly better compared to the untreated patients (stage I cancer, p = 0.0001; stage II cancer, p = 0.001). The median survival time of patients with stage I disease who underwent radiotherapy was 21 months compared to 14 months for untreated patients. Stage II patients who received and did not receive radiation therapy had median survival times of 14 and 9 months, respectively. The survival of treated and untreated patients was not significantly different approximately 5 years after diagnosis (stage I disease, 15% vs 14%, respectively; stage II disease, 11% vs 10%, respectively). In multivariate analysis, radiation therapy was significantly associated with improved lung cancer survival after controlling for age, sex, race, and tumor histology.
Conclusions: These results suggest that radiotherapy is associated with improved survival in patients with unresected stage I or II non-small cell lung cancer. The observed improvement in median survival time was only 5 to 7 months, and radiotherapy did not offer the possibility of a cure.