Lung cancer is the leading cause of cancer-related deaths, worldwide. Complex interactions between genetic, hormonal, behavioural, and environmental factors play a role in the development of lung cancer. Smoking is a major risk factor for lung cancer and accounts for 80% of the lung cancers in men and at least 50% of the lung cancers in women, worldwide. It is estimated that in 2015, 26,600 Canadians will be diagnosed with lung cancer which represents 14% of all new cancers detected and that 20,900 Canadians will die from lung cancer, which represents 27% of all cancer deaths in Canada in 2015. In Canada, the 5-year survival rate for lung cancer patients is 14% and is considerably lower compared with 5-year survival rate for other cancers such as 95% for prostate cancer, 88% for breast cancer, and 65% for colorectal cancer. A contributor to the lower survival rate is the fact that lung cancer is generally diagnosed at an advanced stage when patients present with symptoms and when cure by surgery is unlikely. Screening strategies enabling detection of lung cancer at an early stage could potentially lead to decreased mortality. Screening strategies for lung cancer include conventional radiography, sputum cytology, and the more recent low-dose computed tomography (LDCT). Results with conventional radiography and sputum cytology have been shown to detect slightly more early-stage lung cancers, though this was not accompanied by a reduction in advanced lung cancer detection and did not lead to a reduction in mortality. A large randomized controlled trial, the National Lung Cancer Screening Trial (NLST) showed that with LDCT screening, a 20% reduction in mortality was achieved. However, the false-positive rate is high for screening with LDCT and this can lead to harm due to unnecessary workups of benign nodules. Hence there is debate regarding the use of LDCT for lung cancer screening.
The purpose of this report is to review the clinical effectiveness and safety, diagnostic accuracy, cost-effectiveness, and evidence-based guidelines on the use of LDCT for lung cancer screening.
Disclaimer: The Rapid Response Service is an information service for those involved in planning and providing health care in Canada. Rapid responses are based on a limited literature search and are not comprehensive, systematic reviews. The intent is to provide a list of sources of the best evidence on the topic that CADTH could identify using all reasonable efforts within the time allowed. Rapid responses should be considered along with other types of information and health care considerations. The information included in this response is not intended to replace professional medical advice, nor should it be construed as a recommendation for or against the use of a particular health technology. Readers are also cautioned that a lack of good quality evidence does not necessarily mean a lack of effectiveness particularly in the case of new and emerging health technologies, for which little information can be found, but which may in future prove to be effective. While CADTH has taken care in the preparation of the report to ensure that its contents are accurate, complete and up to date, CADTH does not make any guarantee to that effect. CADTH is not liable for any loss or damages resulting from use of the information in the report.
