A clinical assessment of radiation pneumonitis in cases with lung cancer receiving chemoradiotherapy

We assessed critical factors for development of radiation pneumonitis in 66 patients, who receive radiation therapy with a total dose of more than 30 Gy for primary lung cancer and were followed for more than 3 months during the period from September 1997 to December 1999 in our department. Thirteen cases were diagnosed as having radiation pneumonitis. Radiation pneumonitis occurred more frequently in cases receiving chemoradiotherapy than in those receiving irradiation only. The incidence was significantly higher among patients with small cell lung cancer, especially when radiation and chemotherapy were administered concurrently (p<0.01). In concurrent chemoradiotherapy cases there was a significant difference in the duration of the administation of granulocyte-colony stimulating factor (G-CSF) between the pneumonitis cases (mean-7.3 days) and the non pneumonitis cases (mean-2.1 days) (p<0.01). The duration of G-CSF administration during irradiation was presumed to be a critical factor contributing to radiation pneumonitis. (author)