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For years, more and more Canadians have faced the often deadly diagnosis of lung cancer. The condition can be hard to detect, and thus difficult to treat.
Almost 100 people every day are expected to be diagnosed with lung cancer in Canada, which is a concerning statistic.
For Lung Cancer Awareness Month, which is recognized in November, Yahoo Canada spoke to Dr. Susanna Yee-Shan Cheng, a Medical Oncologist at Sunnybrook Health Sciences Centre, about the condition and how you might be able to prevent it.
Read on to learn more about lung cancer, its causes and key warning signs.
What is lung cancer?
Cancer is a disease in which cells in the body grow out of control.
According to the Canadian Cancer Society, "lung cancer starts in the cells of the lung," and when it starts in lung cells, "it is called primary lung cancer."
Lung cancers are usually grouped into two main types called small cell and non-small cell.
Non–small cell lung cancer usually starts in glandular cells on the outer part of the lung, and small cell lung cancer usually starts in cells that line the bronchi in the centre of the lungs. Non–small cell is more common.
According to Cheng, while lung cancer might not be as common as skin or breast cancer for example, it's the mortality rate that's concerning.
"Lung cancer is actually the number one cause of cancer death. It is common but it’s actually the mortality that’s the biggest issue."Dr. Susanna Cheng
"Lung cancer is actually the number one cause of cancer death," says Cheng. "It is common but it’s actually the mortality that’s the biggest issue. Stage by stage lung cancer is prognostically worse than most cancers."
What causes lung cancer?
Cheng says that smoking is "the number one cause" of lung cancer. As per Lung Cancer Canada, the majority of lung cancer cases – about 85 per cent — are directly related to smoking tobacco, particularly cigarettes.
Smoking increases lung cancer risk by:
• Causing genetic changes in the cells of the lungs
• Damaging the lungs’ normal cleaning process by which they get rid of foreign and harmful particles
• Lodging cancer-causing particles in the mucus and developing into cancer tumours
However, Cheng reveals that there's a "growing number of patients who are non-smokers."
"In particular, we're now seeing patients who’ve never smoked or never had second-hand smoke exposure developing lung cancer, which is interesting because usually smoking is a key cause," explains Cheng. "There's a number of patients who are never smokers and might not have a reason to get lung cancer, so that’s the concerning part."
Cheng says that "we don't know why" non-smokers develop lung cancer, so more research needs to be done. However, her best guess is that it's "related to certain hormones."
That said, the main focus on lung cancer screening is for people with a history of smoking and who are between the ages of 55-70 years old.
Unfortunately, Cheng adds that "the system doesn’t allow for never smokers to be screened."
"We're now seeing patients who’ve never smoked or never had second-hand smoke exposure developing lung cancer."Dr. Susanna Cheng
What are the signs and symptoms of lung cancer?
In its early stages, lung cancer might not cause any signs or symptoms. As the tumour grows and causes changes in the body, it usually results in coughing and shortness of breath.
However, if you have any of the below signs and symptoms that are linked to lung cancer, it's important you see a doctor or medical professional as soon as possible:
A cough that gets worse or doesn't go away
Shortness of breath
Chest pain that you can always feel, and that gets worse with deep breathing or coughing
Blood in mucus coughed up from the lungs
Hoarseness or other changes to your voice
Swollen lymph nodes in the neck or above the collarbone
Cheng notes that she usually sees "cough, infection or pneumonia" as precursors to lung cancer.
However, she reveals that "COVID put a stint in it."
"Nowadays when someone has has COVID they they can be coughing for weeks and weeks," she says. "Some cannot really tell what the symptoms are for sometimes, which can make it hard to diagnose at first."
She adds that cough, shortness of breath (especially when moving), unexplained weight loss, loss of appetite, chest pain, and hoarse voice are other possible warning signs of lung cancer.
"In smokers they may always have a chronic cough but in non-smokers they may never have a cough or develop it over time. Which can delay a lung cancer diagnosis," adds Cheng.
How is lung cancer diagnosed and treated?
Lung cancer is usually diagnosed after a visit to your family doctor, who will ask you about your health history, symptoms, and perform a physical exam. You may also take a blood test, or get an X-ray, MRI or CT scan.
If lung cancer is diagnosed, other tests are done to find out how far it has spread through the lungs, lymph nodes, and the rest of the body. This process is called staging.
Screening for lung cancer is another important step that can help detect the condition early. With lung cancer, early detection is vital. The sooner the disease is diagnosed, the greater chances of survival.
"It’s unfortunate that there isn’t really screening for people who aren’t smokers yet, but hopefully soon."Dr. Susanna Cheng
"It’s unfortunate that there isn’t really screening for people who aren’t smokers yet, but hopefully soon," says Cheng.
When it comes to treatment, Cheng believes it's going in a positive direction.
"In the last 20 years things have transformed significantly. We used to only have chemotherapy, but now it's based on their pathology and their genetic mutations, which predicts what kind of treatment they get, such as immunotherapy and targeted drugs," Cheng explains.
How can I prevent or reduce the risk of lung cancer?
Unfortunately, not all lung cancers can be prevented. However, there are things you can do to help prevent developing the condition, such as changing the risk factors that you can control.
Cheng says that the first thing you can do is to avoid smoking.
"Really, don’t smoke, and try not to be around a loved one who smokes because second-hand smoke risk is also very real," she says.
Cheng adds that there aren't many risk factors related to diet or alcohol, but keep an eye on "occupational exposure."
"Watch occupational exposure like Ephesus. You could also check for radon in your house, but other than that there isn’t really much you could do," she explains.