Major Pathologic Response after Induction Therapy Has a Long-Term Impact on Survival and Tumor Recurrence in Stage IIIA/B Locally Advanced NSCLC.

Background Major pathologic response (MPR) determines favorable outcome in locally advanced non-small cell lung cancer after induction therapy (IT) followed by lung resection. The aim of this retrospective study was to identify the prognostic relevance of MPR in long-term interval. Methods In 55 patients, the survival rate according to MPR and non-MPR was estimated by Kaplan-Meier method and compared using log-rank, Breslow, and Tarone-Ware tests. Results The IT included chemoradiation with 50.4Gy (range: 45-56.4 Gy) combined with platinum-based chemotherapy in 52 patients (94.5%) and platinum-based chemotherapy in 3 patients (5.5%). Perioperative morbidity and 30-day mortality were 36 and 3.6%, respectively. The estimated 5-year postoperative and progressive-free survivals were statistically significantly improved in MPR versus non-MPR with 53.5 versus 18% and 49.4 versus 18.5%, respectively. According to the log-rank, Breslow, and Tarone-Ware tests, the MPR demonstrates prognostic significance in early, long-term, and whole postoperative interval. Conclusion MPR is associated with a robust correlation to long-term postoperative and recurrence-free survival improvement, and can potentially simplify the multidisciplinary debate and allow further stratification of adjuvant treatment in multimodality therapy.