What is the risk of lung cancer in elderly (seniors) individuals in Canada?

From the Guidelines

Lung cancer risk in Canadian seniors is significant, with the average age of diagnosis being 70 years, and seniors being the most affected demographic, particularly those with a history of smoking or other high-risk factors 1. The risk of lung cancer in elderly individuals in Canada is a major concern, with approximately 29,800 new cases diagnosed annually across all age groups, and seniors being the most affected demographic.

• The risk increases substantially after age 60, with smoking remaining the primary risk factor, contributing to about 85% of cases, with a higher prevalence among men though the gap is narrowing as women's smoking rates have increased historically 1.
• Former smokers maintain an elevated risk compared to never-smokers, though this risk decreases gradually over time after quitting.
• Other risk factors for Canadian seniors include radon exposure (the second leading cause), occupational exposures to substances like asbestos and silica, air pollution, and genetic factors.
• Early detection through screening is recommended for high-risk individuals aged 55-74 with a significant smoking history, and annual screening LDCT is recommended until individuals are no longer candidates for definitive treatment, generally defined as curative intent therapy (eg, surgery, chemoradiation, stereotactic body radiation therapy [SBRT]) 1.
• Prevention strategies include smoking cessation at any age (which can reduce risk by up to 50% after 10 years), radon testing in homes, minimizing exposure to environmental pollutants, and maintaining a healthy lifestyle with regular physical activity and a balanced diet.
• The decision to perform lung cancer screening should take into consideration the presence of competing morbidities and patient heterogeneity, potential harms of screening (over-diagnosis, false-positive cases, potential harms of diagnostic tests and the harms of disease treatment) and patient preferences, as highlighted in the management of elderly patients with NSCLC 1.

From the Research

Risk of Lung Cancer in Elderly Individuals in Canada

• The risk of lung cancer in elderly individuals in Canada is a significant concern, particularly among those with a history of smoking 2, 3, 4.
• Studies have shown that low-dose computed tomography (LDCT) can be an effective screening method for lung cancer in high-risk individuals, including the elderly 2, 4, 5, 6.
• The National Lung Screening Trial (NLST) demonstrated a reduction in lung cancer mortality among high-risk current and former smokers aged 55 to 74 years who underwent LDCT screening 6.
• However, the benefits of LDCT screening must be weighed against the potential harms, including false-positive results, radiation-induced cancer, overdiagnosis, and incidental findings 5, 6.
• A study found that the lifetime attributable risk of lung cancer and major cancers after 10 years of CT screening ranged from 5.5 to 1.4 per 10,000 people screened, and from 8.1 to 2.6 per 10,000 people screened, respectively 5.
• The US Preventive Services Task Force recommends annual LDCT screening for smokers aged 55-80, but the Canadian context may differ 3, 4.
• Further research is needed to determine the optimal screening strategy for lung cancer in elderly individuals in Canada, taking into account the unique population characteristics and healthcare system 2, 4.

Screening and Prevention

• LDCT screening can lead to early diagnosis and cure for thousands of patients each year, but clear criteria for screening high-risk patients and disciplined management of abnormalities are necessary to minimize unintended harms and costs 4.
• Older smokers are aware of the risks of smoking and are interested in smoking cessation, but cognitive aspects of participation in screening are key to increasing the uptake of lung cancer screening among high-risk smokers 3.
• Professional societies can help implement a patient-centered program that minimizes unintended harms and costs, and advances in risk assessment tools are urgently needed to address concerns about lung cancer screening 2, 4.