Involved-field radiotherapy alone for early-stage non-small-cell lung cancer.

Purpose: To describe the outcome of involved-field radiotherapy in patients with early-stage non-small-cell lung cancer (NSCLC).
Methods and Materials: A written policy for the radical treatment of early-stage NSCLC with involved-field radiotherapy was adopted at our center in 1986. The sites of known disease were treated to a dose of 52.5 Gy in 20 daily fractions over 4 weeks without elective irradiation of radiologically uninvolved regional nodes. We have reviewed the outcome of this policy in 102 patients treated with radiotherapy alone between 1986 and 1995.
Results: The patients' median age was 71.5 years. The stage distribution was as follows: T1, 33.3%; T2, 56.9%; T3, 8.8%; and T4, 1.0%. Only 5 cases were N1; the remainder were N0. Most patients (76.5%) were not surgical candidates because of co-morbidity. Ninety-three percent had a CT of the thorax as part of their initial staging, while mediastinoscopy was performed in only 16.7%. Overall survival was 35% at 3 years and 16% at 5 years. Recurrence free survival was 23.9% at 3 years and 13. 9% at 5 years. Cause-specific survival was 43.5% at 3 years and 26. 8% at 5 years. Of those who recurred, 68.9% had a local component of failure at initial relapse, and 49.2% failed locally without evidence of regional or distant metastases. Isolated regional nodal relapse at initial failure occurred in only 6.6% of recurrences. There were no treatment interruptions due to acute toxicity and no treatment-related deaths.
Conclusion: Involved-field radiotherapy alone cures a small but significant number of patients with early-stage NSCLC. This approach is recommended in patients who are unfit for surgery and who have severely compromised pulmonary function that would preclude the use of wide-field radiotherapy. The dose used in this study was well tolerated, but produced suboptimal local control rates.