To Evaluate the Role of Postoperative Radiotherapy in Patients With IIIA(N2) Non-Small Cell Lung Cancer

Rationale: Completely resected non-small cell lung cancer (NSCLC) patients with histologically confirmed N2 disease are a heterogeneous population, with 5-year survival rates ranging from 10% to 30%. Systemic recurrence following surgery is one of the major problems in stage IIIA(N2) patients, and the use of postoperative chemotherapy (POCT) in stage IIIA disease prolongs survival. The value of postoperative radiotherapy (PORT) for completely resected NSCLC remains controversial, as the effect on survival has been inconclusive. Recently, several large retrospective studies and reviews of the National Cancer Database indicated that modern PORT appears to confer an additional 5% survival advantage beyond that achieved with adjuvant chemotherapy alone. Actually, after complete resection and POCT, 20%-40% of cases have a risk of locoregional recurrence (LRR). Patients with completely resected stage IIIA(N2) disease might hold different postoperative patterns-of-failure and prognosis. It is not yet known for subsets with specific prognostic factors that confer lower LRR risks, whether giving PORT is more effective than no radiation therapy in treating patients with completely resected pathologic stage IIIA(N2) NSCLC. Purpose: This randomized phase II trial is studying the clinical efficacy of PORT administered using three-dimensional conformal radiotherapy (3D-CRT) techniques and the proposed standard PORT clinical target volume (CTV) delineation guideline in treating low risk of LRR patients with completely resected pathologic stage IIIA(N2) NSCLC.