P61.10 Swiss Pilot Low-Dose Computed Tomography Lung Cancer Screening Study

Abstract

Low-dose computed tomography (LDCT) lung cancer screening is endorsed by United States guidelines and has recently been shown effective in a large European randomized controlled trial. Nevertheless, the actual realization of a lung cancer screening program is challenging and depends on country-specific factors. This pilot study aimed to evaluate implementation, execution and performance of LDCT lung cancer screening in Switzerland. Starting from October 2018, asymptomatic participants aged 55-74 years with more than 30 pack-years smoking history were enrolled at a tertiary hospital in Switzerland. Participants with history of lung cancer, major (palliative) health problems or those that had a thorax CT scan 18 months prior to enrollment were excluded. First line we evaluated lung cancer risk according NLST guidelines. Secondly, we estimated lung cancer risk using the PLCOm2012 model risk calculater with a threshold of 5%. Lung nodules were assessed according Lung-RADS 1.1 {ACoR. Lung-Screening Reporting and Data System (LungRADS) Version 1.1. 2019}. Participants were predominantly recruited through flyers, a newspaper article and pulmonary specialists. Screening consisted of one LDCT-scan and follow-up was recommended for suspicious nodules only. LDCT assessment was performed by two radiologists, one of them a board certified chest radiologist. Enrollment and follow-up are currently ongoing. To date, 75 participants with a median age of 62 years (interquartile range [IQR] 56-67 years) were included. The median number of pack years smoked was 49 (IQR 41-58 pack years) and 25 (33%) were female. The median PLCOm2012 6-year lung cancer probability was 2.7% (IQR 2.6-2.9%) and 19 (26%) participants had stopped smoking before enrollment. Of the 75 participants, 61 (81%) were found to have calcified or non-calcified lung nodules. 6 participants required follow up imaging of suspect nodules which resulted in a recall rate of 8%. At baseline, lung cancer was found in 2 (2.7%) participants. The lung cancers were one squamous cell carcinoma (stage IIIA) and one adenocarcinoma (stage IV). In this Swiss LDCT lung cancer screening pilot study using modified inclusion criteria, lung nodules were found in a significant number of participants of whom 2.7 % were diagnosed with lung cancer to date. To date, the recall rate for follow-up imaging is 8%.