Stereotactic body radiotherapy feasibility for patients with peripheral stage I lung cancer and poor pulmonary function.

The aim of the present study was to evaluate the toxicity and investigate the prognostic factors of stereotactic body radiotherapy (SBRT) for peripheral stage I lung cancer in patients with poor pulmonary function. Data from 95 patients with stage I lung cancer with poor pulmonary function treated using SBRT at Osaka Rosai Hospital were retrospectively analyzed. Poor pulmonary function was defined as the forced expiratory volume %/sec (FEV1/FVC) <70% or percentage of vital capacity (%VC) <80% during pretreatment spirometry testing. The median FEV1/FVC and %VC of the patients were 59.1 and 78.8%, respectively. The most commonly prescribed dose of SBRT was 50 Gy in four fractions (68 patients, 72%). The median follow-up period was 34 months. Four patients developed adverse effects of grade ≥3, one patient developed grade 5 radiation pneumonitis, one grade 5 hemoptysis, one grade 3 radiation pneumonitis and one grade 3 chest wall pain. The 3-year local control and overall survival (OS) rates were 78.8 and 59.9%, respectively. Univariate analysis revealed that Karnofsky performance status (KPS) significantly predicted OS (P=0.037). Thus, SBRT in patients with stage I lung cancer with poor pulmonary function may be effective with acceptable toxicity. A KPS score ≥80 indicated good prognosis.