Peter Chow: Why Are We Still Not Screening For Lung Cancer in Sault Ste. Marie?


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.

In 2020:

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.

Why screen?

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.






    Smoking tobacco, particularly cigarettes, is the main cause of lung cancer.

    There are many chemicals in tobacco smoke, some of which are carcinogenic.

    These include:

    Tobacco-specific nitrosamines
    1,3–butadiene (a hazardous gas)
    Cadmium (a toxic metal)

    The risk of developing lung cancer increases with how long you have smoked, how old you were when you started smoking and the number of cigarettes you smoke each day.


    Nonsmokers who are exposed to secondhand smoke at home or at work increase their risk of developing lung cancer by 20–30%.

    Secondhand smoke causes more than 7,300 lung cancer deaths among U.S. nonsmokers each year.

    Research also suggests that secondhand smoke may increase the risk of breast cancer, nasal sinus cavity cancer, and nasopharyngeal cancer in adults and the risk of leukemia, lymphoma, and brain tumours in children.


    Radon is responsible for about 21,000 lung cancer deaths in the US every year.

    About 2,900 of these deaths occur among people who have never smoked.

    Radon is a colourless, odourless, tasteless gas that comes from the natural breakdown of uranium in rocks and soil.

    In the outdoors, radon gas is diluted by fresh air, so it is not usually a concern.

    But radon can seep into buildings through dirt floors or cracks in the foundations.

    Radon is the leading cause of lung cancer in non-smokers and the second leading cause of lung cancer in smokers.

    The risk for lung cancer from radon is much higher in people who smoke than in those who don’t.


    Asbestos has been widely used in building materials and many industries and causes a type of lung cancer called Mesothelioma.

    The number of Canadian men who receive a diagnosis of Mesothelioma each year has been steadily increasing over the past 20 years, from 153 cases in 1984 to 445 cases in 2016.

    Mesothelioma is generally not diagnosed until 30 or more years after the first exposure; thus, cases are largely the result of asbestos exposure in the 1950s, 1960s and 1970s.

    People who have the highest risk of asbestos exposure include:

    workers in asbestos mines
    workers in oil refineries as in Sarnia
    automotive industry workers, including brake and clutch repair workers
    shipyard workers
    cement plant workers
    plumbing and heating tradespeople
    construction workers, painters, carpenters and electricians


    In Canada, there are approximately 1,900 cases of lung cancer and 450 cases of mesothelioma from workplace exposure diagnosed each year.

    Occupational exposure to the following chemicals increases the risk for lung cancer:

    arsenic and inorganic arsenic compounds
    beryllium and beryllium compounds
    cadmium and cadmium compounds
    chemicals used in rubber manufacturing, iron and steel founding and painting
    chloromethyl ethers and bis(chloromethyl) ether
    diesel engine exhaust
    mustard gas
    radioactive ores such as uranium and plutonium
    silica dust and crystalline silica
    some nickel compounds
    some types of polycyclic aromatic hydrocarbons (PAHs)
    bitumen used in roofing
    cobalt-tungsten carbide
    welding fumes

    People who work in the following industries have the highest risk for lung cancer:

    rubber manufacturing
    iron and steel founding
    coal gasification
    coke production
    oil refining
    chimney sweeping
    commercial painting
    roofing and paving
    industries that use the Acheson process to create silicon carbide


    Air pollution – the combination of particulate matter, and ozone – is a risk factor for many of the leading causes of death including heart disease, stroke, lower respiratory infections, lung cancer, diabetes and chronic obstructive pulmonary disease (COPD).

    Air pollution contributes to 9% of deaths globally in 2017 – this varies from 2% to 15% by country.

    In Canada, 10.7 deaths per 100,000 population.

    There is strong evidence that exposure to different components of outdoor air pollution cause cancer, including diesel engine exhaust, benzene, particulate matter and some PAHs.


    People who had lung cancer have a higher risk of developing lung cancer again. You may also have a slightly higher risk for lung cancer if you have a first-degree relative (a brother, sister, child or parent) who had lung cancer. The increased risk could be due to a number of factors, such as shared behaviours (like smoking) or living in the same place where there are carcinogens (like radon).


    Certain lung diseases or conditions can scar the lungs and increase the risk for lung cancer. Examples of these conditions include:

    chronic obstructive pulmonary disease (COPD), which is long-term damage to the lungs that is often caused by smoking
    emphysema and chronic bronchitis, which are types of COPD
    tuberculosis (TB), which is a lung infection caused by tuberculosis bacteria
    lung infection caused by Chlamydophila pneumoniae


    People who were treated with radiation therapy to the chest for certain cancers, such as Hodgkin lymphoma or breast cancer, have a higher risk for lung cancer.


    Arsenic can get into drinking water from natural sources in the soil or from certain types of industries, such as mining.

    Studies show that high levels of arsenic in drinking water increase the risk for lung cancer.


    Some types of cooking and heating can release pollutants that increase the risk for lung cancer. The levels of these pollutants can be very high in spaces that have poor air flow.

    Burning coal indoors for cooking and heating is most strongly linked to lung cancer.

    Burning wood and other fuels, such as dung or grass, and frying foods in oil at high temperatures can also increase the risk for lung cancer.


    HIV infection and AIDS can weaken the immune system. People with HIV/AIDS have a higher risk of developing many types of cancer, including lung cancer.

    People who have an organ transplant take drugs to suppress their immune system have an increased risk of developing lung cancer.


    People with Systemic lupus erythematosus (SLE or lupus), an autoimmune disease, have a higher risk for lung cancer.


    The following factors have been linked with lung cancer, but there is not enough evidence to show they are known risk factors.

    More research is needed to clarify the role of these factors for lung cancer.


    Researchers are trying to find out if the following chemicals increase the risk for lung cancer:

    bitumen used in paving
    dioxin used in pesticides
    strong chemical acid mists
    fibrous silicon carbide


    Research shows that some families have a strong history of lung cancer, which may mean that they have a mutation in a certain gene that may cause lung cancer.

    Researchers are trying to find out if a specific gene or genes may increase the risk for lung cancer.


    The evidence suggesting a link between long-term smoking of cannabis (marijuana) and cancer is not as strong or as comprehensive as the evidence linking smoking tobacco and cancer.


    Research suggests that people who are not physically active may have a higher risk for lung cancer, whether they smoke or not.


    Some studies report that people who eat a diet high in vegetables and fruit have a lower risk for lung cancer.

  2. The government has succeeded in brainwashing much of the public to believe that ONLY smoking is what causes lung cancer. Blame smoking, blame the smokers, second hand smoke creating division, animosity between people. (Hmm, same thing that’s happening re: covid.) They’ve made a load of money doing it too, in order to pay off the deficit. So much for that. I remember a time when government encouraged smoking! I remember “puffing” on candy cigarettes as a young child. So “Kool”. I’ve come back from walks needing to take a shower, not from sweat but from tiny little particles on me from that steel plant. No doubt I breathed them in too. I practically choke at the smell of gasoline, “natural” gas and diesel fuel. And pesticides… Cancer causing chemicals galore, if you’re not breathing them into your lungs, you’re eating/drinking them…sending them through your esophagus, your colon, bladder, organs. Government won’t put a ban on any of that stuff. Too many jobs would be lost. The economy would fall flat on it’s face. Lung cancer treatment is big business. Often times it only prolongs life for another couple of years. I respect that people will make the choice for treatment though as they have many loved ones they want to spend as much time with as possible and/or they may need to get things in order before they go. I’ll never know if I have cancer of any kind. That’s my choice which I won’t try to force how I do things/the choices I make down other’s throats. It’s my life. Everybody has their own way of thinking and the right to live their life the way they choose unless of course they’re choosing to harm/hurt others (that’s another topic).

    • I worked in the office of a local tire dealership for a few years. At one point I had some testing done and found high levels of chemicals related to tire off-gassing and car exhaust (of course) that are known to be carcinogenic.
      Any time I’ve walked along McNabb or GNR I smell like car exhaust. After thinking about it, most cities I’ve lived in have sidewalks further away from the roads and fumes.
      I travel in & out of town to rural areas often and every time I’m back in town I notice the frequent pollution smell even centrally. Those who have grown up here don’t seem to notice it.
      For the first few years after moving here I experienced many episodes of a very sore throat. The kind I used to get in Hamilton or Toronto during poor air quality days.
      While working as a health & safety coordinator here I had access to draeger air sample units and found that often it read high particulate matter in the Sault air, the air even looked a little hazy but there was rarely anything mentioned about air quality here. Most other places would issue an alert for high particulates in the air. Why is the Sault so different?

      • California has a website, “Proposition 65 Warnings”. It lists chemicals, products and places that cause cancer, reproductive harm, etc. Places like where you worked are mentioned there. The lists are long! I came across it years ago and was shocked. Even my non-stick frying pans were there! I went out and bought cast iron pans, lol. I use my non-stick ones now. I got sick and tired of worrying. Que sera sera!

        • Non-stick cookware contains PFASs.

          Per- and polyfluoroalkyl substances (PFAS) are a group of man-made chemicals that includes PFOA, PFOS, GenX, and many other chemicals.

          PFAS have been manufactured and used in a variety of industries since the 1940s.

          PFOA and PFOS have been the most extensively produced and studied of these chemicals.

          Both chemicals are very persistent in the environment and in the human body – meaning they don’t break down and they accumulate over time – which is why they are called the “Forever Chemicals.”.

          More than 4,700 PFASs exist, an increasing number as industry invents new forms of this type of chemical.

          In 2019, the Trump administration showed its reluctance to aggressively deal with the chemicals, refusing to set limits on PFASs in drinking water.

          PFAS can be found in:

          Food packaged in PFAS-containing materials (milk), processed with equipment that used PFAS, or grown in PFAS-contaminated soil or water.

          Commercial household products, including stain- and water-repellent fabrics, nonstick products (e.g., Teflon), polishes, waxes, paints, cleaning products, and fire-fighting foams.

          A major source of groundwater contamination is from airports and military bases where firefighting training occurs.

          Sault airport has contaminated the groundwater at Pointe des Chenes and Kincheloe Air Force Base has contaminated the groundwater at Kincheloe and surrounding areas.

          Workplace, including production facilities or industries (e.g., chrome plating, electronics manufacturing or oil recovery) that use PFAS.

          Drinking water, typically localized and associated with a specific facility (e.g., manufacturer, landfill, wastewater treatment plant, firefighter training facility).

          Living organisms, including fish, animals and humans, where PFAS have the ability to build up and persist over time.

          The Michigan Department of Health and Human Services (DHHS) issued the warning on Wednesday, March 24, after PFAS chemicals were found in smelt from Lake Superior.

          Due to bio-accumulation, the levels will be even higher in salmon, trout and pickerel.

          Exposure to PFAS can lead to adverse health outcomes in humans.

          The most-studied PFAS chemicals are PFOA and PFOS. Studies indicate that PFOA and PFOS can cause reproductive and developmental, liver and kidney, and immunological effects in laboratory animals.

          Both chemicals have caused tumours in animals.

          The most consistent findings are increased cholesterol levels among exposed populations, with more limited findings related to:

          low infant birth weights,
          effects on the immune system,
          kidney and testicular cancer
          thyroid hormone disruption
          liver toxicity

  3. The city health unit knows that the cancer rate is far higher than other cities and simply doesn’t want to admit it or open that can of worms at all, and you being a doctor should be bringing it up with them not writing an article online that few pay attention to.

    • Government accepts higher numbers of cases of cancer as just part of the cost of doing business.

      In 2019, eight Ontario companies were granted permits that allowed them to emit far more pollution than otherwise permitted by the province’s air-quality standards.

      The ministry exempted the province’s biggest steel mills — ArcelorMittal Dofasco in Hamilton, U.S. Steel in Hamilton and Nanticoke, and Essar Algoma in Sault Ste. Marie — from the new limits coming on emissions of benzene and benzo-alpha-pyrene benzene.

      The exemptions allowed mills to exceed some of the limits by as much as 250 times.

      Essar Algoma (Sault Ste. Marie) also received exemption on emission of Suspended Particulate Matter.

      Why is the sale of cigarettes legal at all?

      Why are First Nations Communities selling cheap cigarettes.

      Everyone, not only in healthcare and public health, but all our leaders, including our local city government have been fully aware of all this for decades, but the political will is sorely lacking.

      It’s not a matter of healthcare providers not conveying the message.

      Just look at how many Saultites would embrace having a chromium refinery inside our city despite the feared health effects.

  4. Funny I should come across this opinion piece – yesterday I spent a little time on Wallace Terrance. The air was hazy, reeked of pollution and after a short while my throat became sore.
    Why are we not screening for cancers more aggressively in a city that has a high cancer rate?
    Likely because it’s another blemish that the city refuses to accept. Also likely, it will identify some polluters that are also important employers.
    This city will bend over backwards for certain things and ignore/neglect others in their efforts to play favourites.
    Build plazas, create new logos, strive for immigration, build fancy new websites, buy magazine advertising and make it look like an article, etc etc. Anything but actually address the root causes of the problems in this city and why there’s such a lack of growth and development.

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