Secondary Analysis of the Rate of Second Primary Lung Cancer From Cancer and Leukemia Group B 140503 (Alliance) Trial of Lobar Versus Sublobar Resection for T1aN0 Non–Small-Cell Lung Cancer

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical trial updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported. Patients with early-stage non–small-cell lung cancer (NSCLC) who undergo curative surgical resection are at risk for developing second primary lung cancer (SPLC). Cancer and Leukemia Group B 140503 (Alliance) was a multicenter, international, randomized, phase III trial in patients with stage T1aN0 NSCLC (using the TNM staging system seventh edition) and demonstrated the noninferiority for disease-free survival between sublobar resection (SLR) and lobar resection (LR). After surgery, patients underwent computed tomography surveillance as defined by the protocol. The determination of a SPLC was done by the treating physician and recorded in the study database. We performed an analysis of the rate of SPLC (per patient per year) and the 5-year cumulative incidence in the study population and within the SLR and LR arms. Median follow-up was 7 years. The rate per patient per year in the study population, in the SLR arm, and in the LR arm was 3.4% (95% CI, 2.9 to 4.1), 3.8% (95% CI, 2.9 to 4.9), and 3.1% (95% CI, 2.4 to 4.1), respectively. The estimated 5-year cumulative incidence of SPLC in the study population, SLR arm, and LR arm was 15.9% (95% CI, 12.9 to 18.9), 17.2% (95% CI, 12.7 to 21.5), and 14.7% (95% CI, 10.6 to 18.7), respectively.