Low-dose CT scan screening available for workers with asbestosis
Patients suffering from work-related asbestosis might be eligible for an early screening program to detect lung cancer. Based on the results of a lung cancer risk assessment tool,1 WorkSafeBC will provide coverage for the BC Cancer Agency (BCCA) to conduct low-dose CT scans on workers with accepted asbestosis claims who are at risk of developing the disease.
Patients suffering from work-related asbestosis might be eligible for an early screening program to detect lung cancer. Based on the results of a lung cancer risk assessment tool,[1] WorkSafeBC will provide coverage for the BC Cancer Agency (BCCA) to conduct low-dose CT scans on workers with accepted asbestosis claims who are at risk of developing the disease.
Dr Stephen Lam and his team at BCCA have reviewed the world literature on this subject, and are hopeful about trial results showing diagnostic scans can offer a survival benefit to individuals in BC with a high lung cancer risk.
Among those facing a high risk of developing lung cancer are asbestosis patients with a history of smoking. Asbestos exposure among individuals who have never smoked is associated with a sixfold increased risk for the development of lung cancer. Individuals with asbestosis who smoke, or have ever smoked, have a fifty-ninefold increased risk of developing lung cancer. WorkSafeBC has identified almost 200 workers with accepted claims for asbestosis, and 80% of them have a history of smoking.
Recently, the US National Cancer Institute undertook a national lung cancer screening study.[2] It involved more than 53000 former smokers and current smokers who were smoking at least 30 packs of cigarettes per year. During random trials, study subjects received either conventional chest X-rays or low-dose, spiral CT screening at the start, and then annually for 2 years. The results indicated a 20% lower death rate among the CT-scan group as compared to the chest X-ray group.
Asbestosis claimants already receive a medical exam, including a chest X-ray, every 2 years. We hope more eligible workers will come forward for the screening as well.
In the absence of regular screening programs, overall outcomes for patients with lung cancer have only shown modest improvements during the past 30 years or more. Recent data from the Canadian cancer registry suggests less than 18% of patients survive beyond 5 years after diagnosis. An early detection tool might improve the prognosis for workers with asbestosis.
Currently, no other randomized trials provide enough evidence to dispute the apparent benefits of low-dose CT scan screening for early detection of lung cancer. However, this debate continues within the current literature.[3]
How to apply for screening
If you have a patient diagnosed with asbestosis who meets the WorkSafeBC criteria for low-dose CT scan screening for lung cancer, WorkSafeBC will contact that individual directly. If your patient is interested and provides consent to participating in the BCCA screening program, WorkSafeBC will forward the information to the BCCA for review and possible inclusion in the program. WorkSafeBC will also request copies of all consultations, imaging studies, lab, and pulmonary function tests be sent by BCCA to both the primary care physician and any specialists involved in the patient’s care.
For more information
To learn more about the low-dose CT scan screening program, contact Lloyd Hikida, WorkSafeBC senior manager of client services for Occupational Disease Services, at 604 276-3317.
—Craig Martin, MD
WorkSafeBC Senior Medical Advisor, Evidence-Based Practice Group
—Celina Dunn, MD, CCFP
WorkSafeBC Manager, Medical Services
—Lloyd Hikida
WorkSafeBC Senior Manager of Client Services, Occupational Disease Services
This article is the opinion of WorkSafeBC and has not been peer reviewed by the BCMJ Editorial Board.
References
1. Tammemagi M, Lam S, Tan W, et al. for the Pan-Canadian Early Detection of Lung Cancer Study Research Team. Pulmonary function as a predictor of lung cancer risk. Presented at the 14th World Lung Cancer Conference. Amsterdam, Netherlands, 3-7 July 2011.
2. Aberle DR, Adams AM, Berg CD, et al. National Lung Screening Trial Research Team. Reduced lung-cancer mortality with low-dose computed tomographic screening. N Engl J Med 2011;365:395-409.
3. Silvestri GA. Screening for lung cancer: It works, but does it really work? Ann Intern Med 2011;155:537-539.