Impact of patient selection and treatment strategies on outcomes after lobectomy for biopsy-proven stage IIIA pN2 non-small cell lung cancer

Abstract

OBJECTIVES: We evaluated the impact of patient selection and treatment strategies on long-term outcomes of patients who had lobectomy after induction therapy for stage IIIA pN2 non-small cell lung cancer (NSCLC). METHODS: The impact of various patient selection, induction therapy and operative strategies on survival of patients with biopsy-proven stage IIIA pN2 NSCLC who received induction chemotherapy ± radiation followed by lobectomy from 1995 to 2012 was assessed using Cox proportional hazards analysis. RESULTS: From 1995 to 2012, 111 patients had lobectomy for stage IIIA pN2 NSCLC after chemotherapy ± radiation with an overall 5-year survival of 39%. The use of induction chemoradiation decreased over time; from 1996 to 2007, 46/65 (71%) patients underwent induction chemoradiation, whereas from 2007 to 2012, 36/46 (78%) patients underwent induction chemotherapy. The use of video-assisted thoracoscopic surgery (VATS) increased over the time period of the study, from 0/26 (0%) in 1996-2001, to 4/39 (10%) in 2002-07 to 33/46 (72%) in 2008-12. Compared with patients given induction chemotherapy alone, patients given additional induction radiation were more likely to have complete pathologic response (30 vs 11%, P = 0.01) but had worse 5-year survival in univariable analysis (31 vs 48%, log-rank P = 0.021). Patients who underwent pathologic mediastinal restaging following induction therapy but prior to resection had an improved overall survival compared with patients who did not undergo pathologic mediastinal restaging (5-year survival: 45.2 [95% confidence interval (CI): 33.9-55.9] vs 13.9% (95% CI: 2.5-34.7); log-rank, P = 0.004). In multivariable analysis, the particular induction therapy strategy and the surgical approach used, as well as the extent of mediastinal disease were not important predictors of survival. However, pathologic mediastinal restaging was associated with improved survival (HR 0.39; 95% CI: 0.21-0.72; P = 0.003). CONCLUSIONS: For patients with stage IIIA pN2 NSCLC, the VATS approach or the addition of radiation to induction therapy can be selectively employed without compromising survival. The strategy of assessing response to induction therapy with pathologic mediastinal restaging allows one to select appropriate patients for complete resection and is associated with a 5-year overall survival of 39% in this population.