Extended resection for potentially operable patients with stage III non-small cell lung cancer after induction treatment.

Surgical treatment of locally advanced non-small cell lung cancer including single or multilevel N2 remains a matter of debate. Several trials demonstrate that selected patients benefit from surgery if R0 resection is achieved. We aimed to assess resectability and outcome of patients with locally advanced clinical T3/T4 (American Joint Committee on Cancer 8<sup>th</sup> edition) tumors after induction treatment followed by surgery in a pooled analysis of 3 prospective multicenter trials. A total of 197 patients with T3/T4 non-small cell lung cancer of 368 patients with stage III non-small cell lung cancer enrolled in the Swiss Group for Clinical Cancer Research 16/96, 16/00, 16/01 trials were treated with induction chemotherapy or chemoradiation therapy followed by surgery, including extended resections. Univariable and multivariable analyses were applied for analysis of outcome parameters. Patients' median age was 60 years, and 67% were male. A total of 38 of 197 patients were not resected for technical (81%) or medical (19%) reasons. A total of 159 resections including 36 extended resections were performed with an 80% R0 and 13.2% pathological complete response rate. The 30- and 90-day mortality were 3% and 7%, respectively, without a difference for extended resections. Morbidity was 32% with the majority (70%) of minor grading complications. The 3-, 5-, and 10-year overall survivals for extended resections were 61% (95% confidence interval, 43-75), 44% (95% confidence interval, 27-59), and 29.5% (95% confidence interval, 13-48), respectively. R0 resection was associated with improved overall survival (hazard ratio, 0.41; P < .001), but pretreatment N2 extension (177/197) showed no impact on overall survival. Surgery after induction treatment for advanced T3/T4 stage including single and multiple pretreatment N2 disease resulted in 80% R0 resection rate and 7% 90-day mortality. Favorable overall survival for extended and not extended resection was demonstrated to be independent of pretreatment N status