New recommendations suggest screening with low-dose CT scan for high-risk populations should take place in controlled environments
March 7, 2016 (Toronto) – A new guideline on screening for lung cancer with low-dose CT technology presents a new opportunity for the control of lung cancer – currently Canada’s most common cause of cancer death.
The Canadian Task Force on Preventive Health Care now recommends screening using low-dose CT scans in high-risk adults aged 55-74 years who are current or former smokers with a smoking history of at least 30 pack-years, defined as the average number of packs smoked daily multiplied by the number of years of smoking.
A recent study found a 15 per cent reduction in lung cancer mortality associated with screening using low-dose CT scans compared to chest x-ray.
However, CT scans carry the risk of exposure to radiation and a positive scan could lead to an invasive procedure, such as a lung biopsy. Because of this, screening should be monitored and controlled in order to minimize harms and maximize the benefits through appropriate follow-up. It should also only be offered to a restricted group of people identified as high-risk, as the risk/benefit ratio is only known for this group.
“It’s always good news to have new possibilities to decrease mortality from this very common cancer. However, any program performing these tests needs to be able to collect information on their results, to ensure quality. Data also need to be collected to add to further knowledge on such issues as the frequency of screening after the first three tests,” said Dr. Heather Bryant, Vice President, Cancer Control at the Canadian Partnership Against Cancer (the Partnership) and chair of the Pan-Canadian Lung Cancer Screening Network.
An estimated 26,600 Canadians were diagnosed with lung cancer in 2015, and almost as many – 20,900 – died from the disease. Those with a history of heavy smoking are at the greatest risk of developing lung cancer.
“Most lung cancers are not symptomatic until they have advanced to late stages of the disease and are incurable. That’s why it’s encouraging to see these guidelines, which recommend a screening test that could lower mortality – representing a chance to save lives,” said Dr. Natasha Leighl, President of Lung Cancer Canada.
“These guidelines translate evidence into action,” said Dr. Stephen Lam, a Distinguished Scientist in the Department of Integrative Oncology at the BC Cancer Agency Research Centre and principal investigator with the Pan-Canadian Early Lung Cancer Detection Study. “To realize the full benefits of low-dose CT screening outside of a study setting, further research will be required.”
Screening must be paired with high quality smoking cessation programs to support people who are still smoking at the time of screening. A 2013 review found that, because smoking reduces the effectiveness of many cancer treatments and increases the likelihood of complications and death in cancer patients, quitting smoking can be beneficial.
Questions raised by the Task Force recommendation include how often screening should be performed, how to handle positive scans and whether screening can benefit those with other lung cancer risk factors. These questions can only be answered by carefully following the results as screening begins.
To advance the consideration of lung cancer screening programs in provinces and territories, the Partnership facilitated the development of a Lung Cancer Screening Framework, which speaks to some of the implementation issues at the provincial and territorial level, including screening eligibility, radiologic testing, pathology quality and reporting, diagnostic treatment and follow-up, and the inclusion of smoking cessation programs.
The Canadian Task Force on Preventive Health Care was established by the Public Health Agency of Canada to develop clinical practice guidelines that support primary care providers in delivering preventive health care. Guideline development is based on systematic analysis of scientific evidence.
Kari Kerr, Director of Communications
Canadian Partnership Against Cancer
416-619-5741 or 647-242-1053
About the Canadian Partnership Against Cancer
The Canadian Partnership Against Cancer works with Canada’s cancer community to reduce the burden of cancer on Canadians. Grounded in and informed by the experiences of those affected by cancer, the organization works with partners to support multi-jurisdictional uptake of evidence that will help to optimize cancer control planning and drive improvements in quality of practice across Canada. Through sustained effort and a focus on the cancer continuum, the organization supports the work of the collective cancer community in achieving long-term population outcomes: reduced incidence of cancer, less likelihood of Canadians dying from cancer, and an enhanced quality of life of those affected by cancer.