- Histologically confirmed unresectable non-small cell carcinoma of the lung (adenocarcinoma, squamous cell carcinoma or anaplastic large cell carcinoma). See below for TNM eligibility. Mediastinoscopy or thoracoscopy in patients with mediastinal lymph node enlargement of < 2 cm on CT scans of suspicious on PET scan to confirm suspected involvement. These staging procedures are not mandatory for patients with obvious nodal involvement (2.0 cm or greater). Staging system: The New International Staging System for lung cancer (Clifton F. Mountain, 1997) will be followed. The following stages will be eligible: