Local irradiation alone for peripheral Stage I lung cancer: Could we omit the elective regional nodal irradiation?

Purpose: The results of local irradiation only for patients with Stage I lung cancer were analyzed to see whether the treatment of regional lymph nodes could be omitted. Methods and Materials: One hundred and eight medically inoperable patients with nonsmall cell lung cancer (T1 and peripheral T2) were treated with 60 Gy split course or 65 Gy continuous treatment, The target volume included the primary tumor only, without regional lymph nodes, Response, survival, and patterns of failure were analyzed. Results: The overall response rate was 85% with 50 (46%) complete responses (CRs). Overall survival at 3 and 5 years was 31 and 15%, and cancer-specific survival was 42 and 31% at 3 and 5 years, respectively. The actuarial 5 years local relapse free survival in patients with a CR was 52%, Tumor size (less than or equal to 4 cm) was strongly correlated with the chance of complete remission and better survival, Of patients in complete remission, only two had a regional recurrence as the only site of relapse; an additional two patients had a locoregional recurrence. Conclusion: High-dose local radiotherapy on the primary tumor only is justified for medically inoperable patients with peripherally located nonsmall lung cancer, The low regional relapse rate does not support the need for the use of large fields encompassing regional lymph nodes, Using small target volumes, higher doses can be given and better local control rates can be expected.