Dynamics of recurrence after curative resection of nonsmall cell lung cancer

Background and Objectives: This study examined the trend of hazards for postoperative recurrence of lung cancer according to pathologic stages.Methods: We reviewed the records of 1987 patients who underwent resection for lung cancer between 2007 and 2012. Postoperative recurrence and development of second primary lung cancer were analyzed to evaluate the trend of hazard rate.Results: Recurrence-free survival (RFS) probabilities at 5 postoperative years in patients with stage I/II/III disease were 87.8%/54.7%,/33.4%, respectively. The hazard rate of RFS was consistently low (<0.005) for stage I patients for 5 years after surgery. The hazard rate of RFS for stage II patients showed a peak of 0.016 at 12.4 months after surgery, and that for stage III patients had a higher peak of 0.029 at 13.7 months after surgery, after which they showed a gradual decrease. The hazard rate for the development of second primary lung cancer exceeded that of recurrence of first primary lung cancer after 72 months postoperatively.Conclusions: Short-interval postoperative surveillance might be unnecessary for stage I patients but should be considered in stage II/III patients. Screening of second primary lung cancer rather than surveillance of recurrence might be beneficial after more than 6 years postoperatively.