Lung cancer becoming more common among non-smokers
30 Nov 2022 09:10am
Current guidelines recommend screening for lung cancer if the person is or was a heavy smoker, above 40 years old and has a family history of lung cancer.
KUALA LUMPUR - In 2019, Suzana Othman started coughing and did not stop.
It punctuates her life and words. When she speaks, coughs break up her flow of words. She often has to stop to catch her breath.
There seemed no reason for her cough and shortness of breath. She is not a smoker. Maybe it was the smell of paint on her newly-painted walls irritating her lungs. Maybe it was pneumonia. Whatever it is, she was desperate for it to stop.
"Strepsils was always in her mouth,” said Syahzanani Salim, her 25-year old daughter.
Suzana still thought nothing of it until one day, after a violent bout of coughing, she hacked up some brown phlegm.
"I realised that I was coughing up phlegm with visible streaks of blood in it. Even though I took some cough mixture, I was still bleeding,” she told Bernama from her hospital bed.
By then, she had lost a lot of weight. She went to see a doctor and got an X-ray done, and underwent a battery of tests.
In January 2021, Suzana was diagnosed with lung cancer.
The 53-year old mother of two was in shock. If she got cancer, she expected it to be breast cancer since her mother had died from it.
Although she has been married to a smoker for 27 years, how could she, a non-smoker her whole life or never-smoker, get lung cancer?
It’s a question that doctors dealing with lung cancer are hard-pressed to answer.
CANCER AMONG NEVER-SMOKERS
Although cigarette smoking is still the biggest contributor to lung cancer - it is the most common cancer among Malaysian men, of which 41 per cent smoke - it is not the only cause for lung cancer.
Environmental risk factors, such as passive smoking, radon exposure and air pollution, are known to cause cancer among never or non-smokers.
"Traditionally, it’s always been a man’s disease. When I was in medical school we equated lung cancer with men and smokers,” said Dr Anand Sachithanandan, president of the Malaysian Lung Cancer Network.
"Now, we’re starting to see high incidence of lung cancer among non-smokers. (It’s) very alarming. Not just in Malaysia, across the world and everybody is quite perplexed wondering why is it the case,” he added.
The World Health Organisation listed air pollution as another cause of lung cancer in 2013.
In the United States, air pollution is responsible for one to two per cent of lung cancers.
In September this year, researchers found that air pollution causes lung cancer by driving mutations in genes linked to lung cancer called KRAS and EGFR. The EGFR gene has been found in half of lung cancers in non-smokers.
Non-smokers are between 10 to 20 per cent of lung cancers in 2021, according to the US Centres for Disease Control. The number has increased from eight per cent in 2017.
There are no specific figures for lung cancer patients based on their tobacco habit in Malaysia.
Dr Anand estimated that almost a third of all lung cancer patients here have never smoked, citing anecdotal evidence.
Available figures in Malaysia found that lung cancer is the fifth most common cancer among women even though only 1.1 per cent of women smoke, according to the 2019 National Health and Morbidity Survey.
In the 2018 Malaysian Study on Cancer Survival, lung cancer cases occurring in women - at 2,478 - were almost half the number in men - at 5,543 - despite the former’s low rates of tobacco use. Non-smoking women who develop lung cancer also tend to be younger.
Hospital Kuala Lumpur consultant clinical oncologist Dr Vaishnavi Jeyasingam told Bernama second-hand cigarette smoke was likely the cause but added there was no way to tell for sure.
Unlike the United States, Malaysia does not have any studies that pinpoint which environmental factor has the most detrimental effect on non-smokers.
"The problem with passive smoking is (you have to look) in terms of quantifying exposure, duration of exposure, how close is the contact. And studies looking into passive smoking and causing cancers are not as robust as smokers and causation,” she said.
On top of the current factors, experts could not be certain whether lung cancer cases will increase in the future due to the COVID-19 pandemic. However, Dr Anand would not be surprised if it did after 10 to 20 years.
"Any condition that causes inflammation of the lungs; so as the lungs heal, there’s maybe scarring and we do not know the long term effects ... It is possible (that) scar tissue we see increases the risk of lung cancer,” he said, pointing to how tuberculosis increases one’s risk of lung cancer.
SCREENING
When it comes to non-communicable disease, conventional wisdom says screening is the best way to either prevent or catch it early enough to treat it. With cancer, the stage at which the disease is detected determines the success rate.
But lung cancer is different. Dr Vaishnavi said early screening is unlikely to work well as it is difficult to target who needs it as it requires access to CT scans, and can give false positive results.
"In our country, unfortunately, we still see a majority of patients being diagnosed at Stage IV because that’s the stage that they usually become symptomatic, or they have cough or weight loss,” she said.
She said if someone came in with early stage lung cancer, it is usually because doctors had detected it by accident or because they had undergone full-body screening through their workplace, for example.
And if one were like Suzana, a non-smoker who lives with a heavy smoker, it is even harder to detect the cancer early.
Current guidelines recommend screening for lung cancer if the person is or was a heavy smoker, above 40 years old and has a family history of lung cancer.
However, they said this should not stop anyone from requesting a lung cancer screening or a full body check-up, and encouraging the public to be more proactive in taking care of their health.
If cost was an issue, many medical NGOs and organisations provide free or affordable screening programmes for the public.
The Lung Cancer Network recently partnered up with Astra Zeneca and Qualitas Medical Group to provide free lung cancer screening, which uses Artificial Intelligence to predict lung cancer nodules from the X-ray.
However, the uptake of such programmes is usually very poor.
"Many people have gone for the X-ray once, and roughly two to three per cent would have an abnormal finding, which may or may not be underlying lung cancer. Our difficulty is closing that loop. Getting those people to then go on and (follow up),” said Dr Anand.
So screening is not an effective solution currently. What is?
Another, and arguably the best option, is prevention.
PREVENTION
Prevention may be the best cure but convincing Malaysians not to light up has been an uphill battle.
Despite all of the government and NGOs’ efforts to curb smoking and help people to quit, the smoking rate has not gone down much.
According to Malaysia’s 2020 report to the WHO Framework Convention on Tobacco Control (FCTC), smoking rates went down to 21.3 per cent in 2019 from 22.8 per cent in 2015.
As such, many healthcare staff supported the Tobacco and Smoking Products Control Bill mooted by former Health Minister Khairy Jamaluddin Abu Bakar, saying this was the best hope to reduce the incidence of cancer and other smoke-related diseases. The bill would ban tobacco sale and possession of tobacco products to anyone born after 2007, among others.
Doctors told Bernama they hoped the new government would keep working on the bill, saying the tax revenue was not enough to cover the healthcare costs from tobacco use.
"Being in the field of oncology, we really do see the effects of tobacco. It’s not only cancers, heart problems, strokes ... our healthcare system is spending so much treating all these preventable things,” said Dr Vaishnavi.
"If Singapore could get away with banning chewing gum, (tobacco) has far worse health implications,” she added.
And if all else fails, there is some small consolation. Lung cancer is no longer the automatic death sentence it was. Treatments have improved in the past few years that many have been able to extend their lives by a few more months.
Dr Anand said some of the progress meant doctors could personalise and provide targeted treatment to the person, depending on the case and availability of the drugs.
"You might die with the cancer and not from it,” he said.
Suzana is placing her hopes on that. At Stage IV, she knows her time is running out. She desperately wants to be healthy enough to perform her umrah with her family in February next year.
But for now, she is enjoying what time she has left with her 55-year old husband, who resigned to take care of her, and her two adult children.
"Take care of yourself. Don’t let anyone smoke around you. And go for check up (and) early detection, especially if you live with a smoker,” she said gently.
SIDEBAR
According to Cleveland Clinic at https://my.clevelandclinic.org/health/diseases/12194-cancer#:~:text=Stage%20I%3A%20The%20cancer%20is,or%20areas%20of%20your%20body, most cancers have four stages.
The specific stage is determined by a few different factors, including the tumour’s size and location.
At Stage I: The cancer is localised to a small area and hasn’t spread to lymph nodes or other tissues; Stage II: The cancer has grown, but it hasn’t spread; Stage III: The cancer has grown larger and has possibly spread to lymph nodes or other tissues and Stage IV: The cancer has spread to other organs or areas of your body. This stage is also referred to as metastatic or advanced cancer.
Though stages one through four are the most common, there’s also a Stage 0. This earliest phase describes cancer that’s still localised to the area in which it started.
Cancers that are still in Stage 0 are usually easily treatable and are considered pre-cancerous by most healthcare providers. - BERNAMA
