Several important international randomized trials have shown that postoperative chemotherapy contributed to the improvement on 5 year survival rate by about 4% for patients with non-small cell lung cancer (NSCLC) after complete resection. But the overall survival rate was relatively low and the local recurrence was still the dominant failure pattern for stage IIIA (N2) disease even these patients received the postoperative chemotherapy. Several meta-analyses have shown that postoperative radiotherapy (PORT) has no effect on the survival improvement for patients with NSCLC after complete resection. However, sub-group analysis based on the same dataset of these meta-analyses showed that the PORT with conventional radiotherapy might be beneficial for stage IIIA (N2) disease. The 3D conform radiotherapy (3D-CRT) and intensity modified radiotherapy (IMRT) can increase the radiation dose to the target volume while decreasing the dose to risk organs comparing with the conventional radiotherapy. So it is expected that PORT using 3D-CRT or IMRT after postoperative chemotherapy will improve the local control and survival for stage IIIA (N2) NSCLC. Here, the investigators designed a phase III randomized trial to compare the 3-year disease free survival (DFS) and overall survival (OS) rates in patients with completely resected stage IIIA (N2) NSCLC who receive adjuvant chemotherapy alone or adjuvant chemotherapy plus PORT.

OBJECTIVES:

Primary: To determine whether administering adjuvant chemotherapy (four cycles of platinum-based doublet regimen) plus PORT (50 Gy, 2 Gy once daily over 5 weeks) will improve 3-year DFS compared with adjuvant chemotherapy alone in patients with completely resected stage IIIA (N2) NSCLC.

Secondary: To compare treatment-related toxic effects, 3-year OS, failure-free survival, and the patterns of failure.

OUTLINE: Eligible patients were randomized equally, using simple randomization, to either PORT or observation group.

Arm I: Patients undergo PORT using 3D-CRT or IMRT (50 Gy, 2 Gy once daily over 5 weeks) after adjuvant chemotherapy.

Arm II: Patients undergo adjuvant chemotherapy.

After completion of study treatment, patients are followed every 3 months for 1 year, every 6 months for 2 years, and then annually thereafter.

Inclusion Criteria:

• Completely resected disease by lobectomy, bilobectomy. Complete dissection of lymph nodes at levels 4, 7, and 10 in case of right-sided thoracotomy and at levels 4 (if accessible), 5, 6, 7, and 10 in case of left-sided thoracotomy.
• Histologically N2 disease after surgery. Negative margins
• Has undergone chemotherapy of four cycles of platinum-based doublet regimen and no recurrence and metastasis

Exclusion Criteria:

• Pregnant or nursing
• ECOG performance status > 1
• Post-operative FEV_1 < 1 L (or < 35% theoretical value, PO_2 < 70 mm Hg, and PCO_2 > 45 mm Hg)
• Severe cardiac disease within the past 6 months, including the following: Arrhythmia, Congestive heart failure, Infarction, Pacemaker
• Severe pulmonary disease within the past 6 months
• Other prior or concurrent neoplasm, except for basal cell carcinoma of the skin or carcinoma in situ of the cervix
• Severe or uncontrolled systemic disease
• Familial, social, geographic, or psychological conditions that would preclude study participation