Purpose: Radiation pneumonitis is a serious complication that develops after thoracic irradiation. The purpose of this study was to identify prognostic factors for severe radiation pneumonitis in patients with non-small-cell lung cancer.
Methods and materials: The medical records of patients with non-small-cell lung cancer and severe radiation pneumonitis were reviewed. Variables were analyzed by univariate and stepwise multivariate analysis using the Cox regression model.
Results: Among the 31 patients, the mortality rate approached 50% in the first 2 months after the onset of radiation pneumonitis. The variables significantly associated with survival in the univariate analysis were tumor histologic feature, grade and extent (out-of-field or in-field) of radiation pneumonitis, oxygenation index, and serum albumin (<35 g/L or >or=35 g/L), and uric acid levels at the onset of radiation pneumonitis. Only the extent of radiation pneumonitis and serum albumin level were independently associated with survival in the multivariate analysis.
Conclusion: The mortality rate of non-small-cell lung cancer patients with severe radiation pneumonitis is extremely high, and survival is much shorter in patients with out-of-field radiation pneumonitis or a low serum albumin level at the onset. Additional studies to investigate the factors precipitating out-of-field radiation pneumonitis should improve the management of irradiation complications.