Risk factors of acute radiation pneumonitis in patients with non-small cell lung cancer after concur-rent three-dimensional conformal radiotherapy and chemotherapy

Abstract

Objective To analyze the incidence and related factors of acute radiation pneumonitis (RP) in patients with non-small cell lung cancer (NSCLC) who underwent three-dimensional conformal ra-diotherapy with concurrent chemotherapy. Methods From January 2006 to October 2008, 90 NSCLC pa-tients treated with concurrent chemoradiotherapy were retrospectively reviewed. The clinical characteristics and treatment plan parameters from dose-volume histogram (DVH) were analyzed. Results Grade 1, 2,3, 4 and 5 RP was found in 32.2%, 30.0%, 5.6%, 0% and 1.1% of the patients. Primary tumor loca-tion was the only significant clinical factor in univariate analysis. And significant differences were found when the groups was divided by the mean lung dose (MLD) of 17 Gy, V5 of 47% ,V10 of 36% ,V20 of 24%,V30 of 23% and V40 of 22%, respectively. Multivariate analysis showed the MLD was the only independent predictive factor of RP. Conclusions Some factors may contribute to the RP. MLD should be set below 17 Gy in three-dimensional conformal radiation, especially when the tumor locates in the lower lobe. Key words: Lung neoplasms/radiotherapy; Radiotherapy, three-dimensional conformal; Lung neoplasms/chemotherapy; Chemotherapy,concurrent; Radiation pneumonitis; Factor analysis