Clinical and dosimetric predictors of radiation pneumonitis in a large series of patients treated with stereotactic body radiation therapy to the lung.

Purpose: To report clinical and dosimetric factors predictive of radiation pneumonitis (RP) in patients receiving lung stereotactic body radiation therapy (SBRT) from a series of 240 patients.

Methods And Materials: Of the 297 isocenters treating 263 patients, 240 patients (n=263 isocenters) had evaluable information regarding RP. Age, gender, current smoking status and pack-years, O2 use, Charlson Comorbidity Index, prior lung radiation therapy (yes/no), dose/fractionation, V5, V13, V20, Vprescription, mean lung dose, planning target volume (PTV), total lung volume, and PTV/lung volume ratio were recorded.