Development of radiation pneumopathy and generalised radiological changes after radiotherapy are independent negative prognostic factors for survival in non-small cell lung cancer patients.

Abstract

To investigate the risk factors for radiation pneumopathy (RP) and survival rate of non-small cell lung cancer patients with RP and generalised interstitial lung changes (gen-ILC). A total of 147 consecutive patients receiving curative radiotherapy were analysed. RP was graded according to Common Terminology Criteria for Adverse Events v. 3. Computed tomography images were assessed for the presence of gen-ILC after radiotherapy. Univariate and multivariate analyses were performed to identify significant factors. Median follow-up was 16.2 months (range 1.4-58.6). Radiological changes after radiotherapy were confined to high dose irradiation volume in 111 patients, while 31 patients developed gen-ILC. Dosimetric parameters and level of C-reactive protein before radiotherapy were significantly associated with severe RP. Development of gen-ILC (p=0.008), as well as severe RP (p=0.03) had significant negative impact on patients' survival. These two factors remained significant in the multivariate analysis. Severe radiation pneumopathy and generalised radiographic changes were significant independent prognostic factors for survival. More studies on pathophysiology of radiation induced damage are necessary to fully understand the mechanisms behind it.