Impact of Timing of Lobectomy on Survival for Clinical Stage IA Lung Squamous Cell Carcinoma

Abstract

Because the relationship between the timing of surgery following diagnosis of lung cancer and survival has not been precisely described, guidelines on what constitutes a clinically meaningful delay of resection of early-stage lung cancer do not exist. This study tested the hypothesis that increasing the time between diagnosis and lobectomy for stage IA squamous cell carcinoma (SCC) would be associated with worse survival. The association between timing of lobectomy and survival for patients with clinical stage IA SCC in the National Cancer Data Base (2006-2011) was assessed using multivariable Cox proportional hazards analysis and restricted cubic spline (RCS) functions. The 5-year overall survival of 4,984 patients who met study inclusion criteria was58.3%(95%CI, 56.3-60.2). Surgery was performed within 30days of diagnosis in 1,811 (36%)patients, whereas the median time to surgery was 38days (interquartile range, 23, 58). In multivariable analysis, patients who had surgery 38days or more after diagnosis had significantly worse 5-year survival than patients who had surgery earlier (hazard ratio, 1.13 [95%CI, 1.02-1.25]; P= .022). Multivariable RCS analysis demonstrated the hazard ratio associated with time to surgery increased steadily the longer resection was delayed; the threshold time associated with statistically significant worse survival was ∼90days or greater. Longer intervals between diagnosis of early-stage lung SCC and surgery are associated with worse survival. Although factors other than the timing of treatment may contribute to this finding, these results suggest that efforts to minimize delays beyond those needed to perform a complete preoperative evaluation may improve survival.