Clinical predictive factors for radiation pneumonitis and pulmonary fibrosis during split course concurrent chemoirradiation for locally advanced non-small cell lung cancer

Abstract

Background: Radiation therapy (RT) remains an important component of the treatment of non-small cell lung cancer (NSCLC). Unfortunately, the use of RT in this context is limited by toxicity to normal tissues, particular normal lung and esophagus. Radiation-induced pulmonary damage typically manifests as radiation pneumonitis (RP), pulmonary fibrosis (PF), or both. A number of prior studies have evaluated clinical and dosimetric predictive factors for these toxicities, with mixed results. At our institution, patients with locally advanced NSCLC are treated either in the definitive setting to 60Gy in 30 fractions or neoadjuvant setting to 44Gy in 22 fractions with a regimen of split course concurrent chemotherapy and RT. The specific details and clinical outcomes of this regimen have been previously published. In this study, we sought to identify clinical features predictive of any pulmonary toxicity (versus none) and/or severe pulmonary toxicity (NCIC CTC Grade 3 or higher RP and/or Grade 2 or higher PF) versus none-mild toxicity using this regimen.