Incidental detection by computed tomography is an independent prognostic factor for survival in patients operated for nonsmall cell lung carcinoma

We studied the rate of incidental detection of lung carcinomas and its effect on long-term survival in a nationwide cohort of patients operated for nonsmall cell lung cancer (NSCLC). All patients operated for NSCLC in Iceland during 1991–2010 were included. Demographic and clinicopathological features were compared in patients diagnosed incidentally using chest radiography or computed tomography (CT), and in those with symptomatic presentation. Multivariate analysis was used to evaluate prognostic factors. Out of 508 patients, 174 (34%) were diagnosed incidentally; in 26% of cases by chest radiography and in 8% by CT. The CT-detected tumours were significantly smaller than symptomatic tumours, diagnosed at earlier TNM (tumour, node and metastasis) stages and more often of adenocarcinoma histology. 5-year cancer-specific survival for symptomatic versus incidentally diagnosed patients detected by chest radiography and CT was 41%, 57% and 68%, respectively (p=0.003). After adjusting for stage, the hazard ratio (HR) for NSCLC mortality was significantly lower for incidental diagnosis by CT (HR 0.55, 95% CI 0.31‒0.98; p=0.04) compared to incidental diagnosis by chest radiography (HR 0.95, 95% CI 0.70‒1.27; p=0.71) or symptomatic diagnosis (HR 1.0). One-third of surgically treated NSCLCs were detected incidentally, with an increasing rate of incidental CT diagnosis. NSCLC patients diagnosed incidentally by CT appear to have better survival than those diagnosed incidentally by chest radiography, and particularly those who present with symptoms. @ERSpublications A third of surgically treated NSCLC cases were detected incidentally; those detected by CT may have better survival http://ow.ly/S24I309M1VK Cite this article as: Orrason AW, Sigurdsson MI, Baldvinsson K, et al. Incidental detection by computed tomography is an independent prognostic factor for survival in patients operated for nonsmall cell lung carcinoma. ERJ Open Res 2017; 3: 00106-2016 [https://doi.org/10.1183/ 23120541.00106-2016]. Copyright ©ERS 2017. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial Licence 4.0. Received: Sept 28 2016 | Accepted after revision: March 05 2017 Support statement: Funding was provided by the Landspitali University Research Fund and the University of Iceland Research Fund. Funding information for this article has been deposited with the Crossref Funder Registry. Conflict of interest: None declared. https://doi.org/10.1183/23120541.00106-2016 ERJ Open Res 2017; 3: 00106-2016 ORIGINAL ARTICLE LUNG CANCER