From 1984 to 1991, 136 patients with histologically confirmed non-small cell lung cancer and stage IIIa (N2) disease received two to three cycles of MVP (mitomycin + vindesine or vinblastine + high-dose cisplatin) chemotherapy. All patients had clinical N2 disease, defined as bulky mediastinal lymph node metastases or multiple levels of lymph node involvement in the ipsilateral mediastinum or subcarinal space on chest roentgenograms, computed tomographic scans, or mediastinoscopy. The overall major response rate to chemotherapy was 77% (105/136). Thirteen patients had a complete response and 92 patients had a partial but major response (> 50%). The overall complete resection rate was 65% (89/136) with a complete resection rate of 78% (82/105) in patients with a major response to chemotherapy. There was no histologic evidence of tumor in the resected specimens of 19 patients. The overall survival was 28% at 3 years and 17% at 5 years (median, 19 months). For patients who had complete resection, the median survival was 27 months and the 3-year and 5-year survivals were 41% and 26%, respectively. There were seven treatment-related deaths, five of which were postoperative deaths. To date, 33 patients, all of whom had complete resection, have had no recurrence after treatment. These results demonstrate that (1) preoperative chemotherapy with MVP produces high response rates in stage IIIa (N2) disease, (2) high complete resection rates occur after response to chemotherapy, and (3) survival is longest in patients who have a complete resection after major response to chemotherapy.