Why are we still not screening for lung cancer routinely in Sault Ste Marie, like we screen for breast cancer, cervical cancer, bowel cancer and prostate cancer???
The science was settled years ago.
If you are a smoker, past or present, discuss with your doctor about a referral to Ontario Lung Cancer Screening at Health Sciences North in Sudbury – it could be life-saving.
29,800 Canadians were diagnosed with lung cancer, 15,000 men and 14,800 women.
This represents 13% of all new cancer cases in 2020.
21,200 Canadians died from lung cancer, 11,000 men and 10,200 women.
Lung cancer is the leading cause of cancer death in Canada, causing 25% of all cancer deaths in 2020, more deaths than colorectal (9,700), breast (5,100) and prostate (4,200) cancers combined.
On average, 81 Canadians are diagnosed with lung cancer every day.
On average, 58 Canadians die from lung cancer every day.
Lung cancer is the most commonly diagnosed cancer in Canada (excluding non-melanoma skin cancers).
It is estimated that about 1 in 14 Canadian men will develop lung cancer during their lifetime and one in 16 will die from it.
About 1 in 15 Canadian women will develop lung cancer during their lifetime and one in 19 will die from it.
The 3-year survival for stage 4 lung cancer is only 5%.
However, for lung cancer cases diagnosed at stage 1, the 3-year survival rises to 71%.
Lung cancer screening in Canada over 20 years would lead to 7,000–17,000 fewer stage 4 diagnoses and 5,000–11,100 fewer deaths.
Lung cancer screening with low-dose computed tomography (LDCT) can find lung cancer in high-risk people before they have any symptoms and help lower their risk of dying from lung cancer.
Low-dose computed tomography uses a computer linked to an x-ray machine that gives off a very low dose of radiation to make a series of detailed pictures from different angles to create 3-D views of tissues and organs.
We do not have this capability at Sault Area Hospital at the present time.
Lung cancer screening using ordinary chest x-rays and sputum test is not recommended as studies show that these tests are not effective in finding lung cancer early.
In 2013, the USPSTF (U.S. Preventive Services Task Force) recommended annual screening for lung cancer with low-dose computed tomography (LDCT) in adults aged 55 to 80 years who had a 30 pack-year smoking history.
(One pack-year is equivalent to smoking an average of 20 cigarettes, or one pack, per day for a year).
In 2016, the Canadian Task Force on Preventive Health Care made the recommendation for screening for lung cancer with three consecutive annual low-dose computed tomography (LDCT) scans in high-risk individuals adults aged 55-74 years who currently smoke or quit less than 15 years ago and who had a 30 pack-year smoking history.
In 2021, the USPSTF now recommends annual screening for lung cancer with low-dose computed tomography (LDCT) in adults aged 50 to 80 years who have a 20 pack-year smoking history and currently smoke or who have quit within the past 15 years.
Screening would be discontinued once a person has not smoked for 15 years or develops a health problem that substantially limits life expectancy or the ability to have curative lung surgery.
In 2018, 15.8% of Canadians aged 12 and older (roughly 4.9 million people) smoked cigarettes either daily or occasionally, 18.6% for adult males and 13.0% for women.
Millions of Canadians fall into the category deemed high risk for lung cancer.
The 3-year survival for lung cancer at stage 4 is only 5%.
However, for lung cancer cases diagnosed at stage 1, the 3-year net survival rises to 71%.
So what is the evidence?
There are currently 2 randomized controlled trials (RCTs) that support lung cancer screening.
The .NSLT (the National Lung Cancer Screening Research Trial Team), a prospective, randomized trial, was conducted between 2002-2011, comparing low-dose computed tomography (LDCT) screening to single-view postero-anterior chest X-ray (CXR) screening for 3 annual screenings.
It enrolled 53,454 high-risk participants ages 55-74 years with current or former 30 pack-year smoking history or having quit within the last 15 years.
A positive screen was a nodule > 4 mm or other finding related to lung cancer.
The incidence of lung cancer was 645 cases per 100,000 person-years in the low-dose CT group, as compared with 572 cases per 100,000 person-years in the chest x-ray (CXR) group.
The relative reduction in mortality from lung cancer with low-dose CT screening compared to CXR screening was 20.0%
The NELSON trial, a Dutch -Belgian lung cancer screening trial published in February 2020, enrolled 15,792 participants between ages 50 and 74 – 13,195 men and 2,594 women – who had a high risk of lung cancer.
They were either current smokers or former smokers, who quit less than 10 years prior, who smoked more than 15 cigarettes a day for more than 25 years or more than 10 cigarettes a day for more than 30 years.
As part of the trial, participants received four rounds of low-dose CT screening at one-year, two-year, and 2.5-year intervals.
Others in the trial received no screenings.
Overall, results showed that LDCT screenings reduced total lung cancer deaths by 24% in men and 33%t in women.
The number needed to screen to prevent one lung cancer death was 130 persons over the screening period.
The NELSON trial provided empiric evidence for a younger starting age and lighter smoking history.
So what are the harms of screening?
1) False-positive nodules leading to unnecessary tests and invasive procedures.
The NSLT false-positive findings lead to invasive procedures like needle biopsies, bronchoscopies, thoracotomies in 1.7% of patients screened, with complications occurring in 0.1% persons screened.
2) Overdiagnosis of cancer – discovery of cancers never destined to cause harm
Modelling predicts 6% of overdiagnosis if new guidelines are implemented.
3) Radiation-induced cancers
The lifetime risk of cancer from radiation of 10 annual LDCT scans was 3 to 5 cancers per 10,000 persons screened.
Modelling predicts the updated guidelines would result in an estimated 19 radiation-related cancer deaths per 100,000 persons (ages 45 to 90 years in the U.S.)
4) Incidental findings other than pulmonary nodules
Common findings include coronary artery calcifications, aortic aneurysms, emphysema, and possible infections and inflammatory processes.
On balance, the benefits vastly outweigh the harms.
So, the research shows that screening with low-dose computed tomography (LDCT) can find lung cancer in high-risk people before they have any symptoms and help lower their risk of dying from lung cancer.
Lung cancer screening using chest x-rays and sputum test is not recommended.
Studies show that these tests are not effective in finding lung cancer early.
Despite good evidence to support lung cancer screening, guideline implementation has been slower than optimal, often absent altogether.
Lung cancer screening in Ontario using low-dose computed tomography (LDCT) was available through the Lung Cancer Screening Pilot for People at High Risk (the pilot program), which ended in March 2021.
The hospitals that participated in the pilot are now part of the Ontario Lung Screening Program, with the plan to add more Ontario Lung Screening Program sites across the province in the future.
Lung cancer screening through the Ontario Lung Screening Program is now available at hospitals in Toronto, Ottawa, Oshawa and Sudbury (Health Sciences North).
The Ontario program screens current and former smokers ages 55 to 74 if they have smoked cigarettes daily for at least 20 years (not necessarily 20 years in a row, which means there could be times when they did not smoke).
Some doctors in Sault Ste Marie are not even aware of the Ontario Lung Screening Program, since, in Northern Ontario, it is available only in Sudbury.
In 2016, the Canadian Task Force on Preventive Health Care made the recommendation for screening for lung cancer with three consecutive annual low-dose computed tomography (CT) scans in high-risk individuals adults aged 55-74 years who currently smoke or quit less than 15 years ago.
So, the question is, why are we still not screening for lung cancer routinely in Sault Ste Marie, like we screen for breast cancer, cervical cancer, bowel cancer and prostate cancer?
If you are a smoker, past or present, talk to your doctor about a referral to Ontario Lung Cancer Screening at Health Sciences North in Sudbury – it could be life-saving.