Stereotactic radiosurgery for the treatment of stage I non-small cell lung cancer in high-risk patients.

OBJECTIVE: Surgical resection is the standard of care for patients with stage I non-small cell lung cancer. For high-risk patients, however, stereotactic radiosurgery may offer an alternative. We report our initial experience with stereotactic radiosurgery for treatment of stage I non-small cell lung cancer by a team of thoracic surgeons and radiation oncologists. METHODS: Patients medically ineligible for operation were offered stereotactic radiosurgery. Thoracic surgeons evaluated all patients, placed fiducials, and performed treatment planning in collaboration with radiation oncologists. Median dose of 20 Gy to 80% isodose line was administered as single fraction (range 20-60 Gy,1-3 fractions). Initial response rate, progression, and survival were monitored. RESULTS: Twenty-one patients underwent stereotactic radiosurgery in 3 years. Fiducial placement resulted in pneumothorax requiring a pigtail catheter in 10 of 21 patients (47%). Disease showed initial response in 12 of 21 patients (57%), was stable in 5 (24%), progressed in 3 (14%), and was not evaluable in 1 (5%). Procedure-related mortality was zero. With mean 24-month follow-up, estimated 1-year survival probability was 81% (68% confidence interval 0.73-0.90). Median survival was 26.4 months (confidence interval 19.6 months-not reached). Local progression occurred in 9 patients (42%). Median time to local progression was 12.3 months (confidence interval 12 months-not reached). CONCLUSION: Preliminary experience indicates that stereotactic radiosurgery (median dose 20 Gy) is safe in this high-risk group; however, it was associated with significant local progression. Further prospective studies with multiple fractions are needed to evaluate its efficacy in this population.