Adjuvant CCRT vs CT in Minimal N2 NSCLC

Approximately 15% of patients with non-small cell lung cancer are diagnosed with stage IIIA-N2 disease. However, this subgroup is heterogeneous, with lymph nodes that are only microscopically invaded to those that are radiologically visible with bulky ipsilateral mediastinal lymph node involvement. Surgical resection in selected patients results in 5-year survival rates of 7-24%.

The standard treatment for locally advanced clinical N2 disease is definitive concurrent chemoradiotherapy or induction chemotherapy (± radiation) followed by operation. However, in some patients, N2 status could be confirmed only after curative operation without any evidence of N2 diseases through preoperative evaluation methods (CT, PET, mediastinoscopy). We usually define those N2 disease found only after curative operation as microscopic N2, and do adjuvant chemotherapy, radiotherapy or concurrent chemoradiotherapy. However, little data about the adjuvant therapy for completely resected N2 disease have been available, Hence, we propose a randomized phase II study of adjuvant concurrent chemoradiotherapy vs chemotherapy alone in completely resected microscopic N2 NSCLC.

Inclusion criteria

• Histologically confirmed diagnosis of stage IIIA(N2) NSCLC that was completely resected by lobectomy, bilobectomy, pneumonectomy, or sleeve lobectomy through any incision (thoracoscopic or video-assisted thorascopic surgery approaches were acceptable)
• "Pathologic N2" disease (involvement of N2 nodes can only be determined at the time of surgical exploration or postoperative pathologic analysis)
• Age ≥18years
• No known residual disease (negative resection margin and no extracapsular invasion of lymph node metastasis)
• ECOG performance status of 0 to 1
• No previous chemotherapy or RT
• Adequate organ function as evidenced by the following; Absolute neutrophil count > 1.5 x 109/L; platelets > 100 x 109/L; total bilirubin ≤1.5 UNL; AST and/or ALT < 5 UNL; creatinine clearance ≥ 50mL/min
• Written informed consent form

Exclusion criteria

• Patients with preoperative mediastinoscopic N2 positive disease
• Uncontrolled systemic illness such as DM, CHF, unstable angina, hypertension or arrhythmia
• Patients with post-obstructive pneumonia or uncontrolled serious infection
• Pregnant or nursing women ( Women of reproductive potential have to agree to use an effective contraceptive method)
• Prior history of malignancy within 5 years from study entry except for a adequately treated basal cell or squamous cell skin cancer or in situ cervical cancer, well-treated thyroid cancer