Late diagnosis of lung cancer results in higher mortality rate
According to the Malaysia National Cancer Registry Report 2012-2016, lung cancer is the third commonly seen cancer in the nation, accounting for at 9.8%. The same report cites colorectal cancer as number two at 13.5%.
However, the survival rates for both are vastly different despite the marginal difference. The Malaysian Study on Cancer Survival (MySCan) 2018 notes that there is a 51.1% chance of five-year relative survival for colorectal cancer but for lung cancer, it is only 11% – the lowest recorded.
It is not just in Malaysia where this is evident; globally, the prognosis for stage IV lung cancer is poor where the survival rate is only around 5%. Why the difference? Evidence points to a late diagnosis in lung cancer, and that makes all the difference between surviving the cancer or not. In Malaysia, only three to four percentages of those diagnosed with lung cancer are in Stage I but up to 90% are already in Stage III or Stage IV.
Even those with the most symptoms are only diagnosed when their cancer is at an advanced stage, says Dr Ronald Lim Chor Kuan, Respiratory and Internal Medicine Specialist, specialising in lung cancer from Regency Specialist Hospital. “This disease causes very limited symptoms and may even be asymptomatic at the early stage, resulting in difficulty in early diagnosis.” Symptoms of lung cancer include cough, chest pain, hemoptysis and shortness of breath, loss of weight or appetite, which many would brush off as a prolonged cold, adding to the reasons why lung cancer is often diagnosed too late. Also, patients’ reluctance to have these symptoms checked out – like a persistent cough – can delay the diagnosis as well.
Despite it being caught late, one of the risk factors for lung cancer is something that can be avoided early on before it impacts your health: Smoking.
It’s a well-known fact that cigarette smoking can lead to lung cancer – whether you are the one smoking or if you are exposed to secondhand smoke. “Approximately 85 to 90% of lung cancer cases are caused by voluntary or involuntary cigarette smoking. There are also a 20 to 30% of increased risks in lung cancer from secondhand smoke exposure associated with living with a smoker. Thus, both active and passive smokers carry the risks of developing lung cancer,” says Dr Lim. Therefore, it is essential for you to snub out that cigarette and make it a point to quit for your health’s sake. In fact, the smoking ban in eateries and restaurants drive the point towards increasing public awareness on the dangers of direct or indirect smoking.
There are also other risk factors for lung cancer, such as family history, existing chronic obstructive pulmonary disease or pulmonary tuberculosis, exposure to ionizing radiation, asbestos, chromium, silica, polycyclic aromatic hydrocarbons and diesel exhaust. Think you’re safe in your home away from all these dangerous elements? Think again: “Never forget of indoor pollutants too as it is a major risk factor for lung cancer in women who’ve never smoked before living in several Asian regions,” says Dr Lim. The fact is anyone can get lung cancer, whether it is because of your lifestyle choices or genetic predisposition.
Treating the Cancer
Lung cancer can be categorised into two types – Small Cell Lung Cancer (SCLC) accounting for 15% of the all cancer cases, and Non-Small Cell Lung Cancer (NSCLC) accounting for 85%. The type you have will determine the kind of treatment you’ll get.
There have been lots of breakthrough improvements in the management of NSCLC, whether it is target therapy, immunotherapy, and chemotherapy as well as anti-angiogenesis therapy. Yet, the treatment efficacy and prognosis for SCLC remains unsatisfactory. “SCLC is a rapid growing cancer cell type with shorter tumor doubling time. Recent two studies added immunotherapy to the standard first line chemotherapy regimen – platinum and etoposide. The treatment arm with added immunotherapy shows significantly prolonged overall survival as compared to chemotherapy alone – these are encouraging results and introduce a new page to the treatment of SCLC, which before 2019 had limited treatment options,” says Dr Lim.
Your doctor will also select the correct treatment according to your cancer stage. For Stage I and Stage II – which are considered as early stage lung cancer – surgical resection is the mainstay of treatment. “Depending on the size and location of the cancer, there are different ways of surgery. For medically inoperable patients, stereotactic ablative radiotherapy is also a choice of treatment”, adds Dr Lim. For stage II disease, neoadjuvant chemotherapy follows by surgery or surgery follows by adjuvant chemotherapy is the optimal treatment option.
While lung cancer is mostly diagnosed at a later stage (Stage IIIB, IIIC or Stage IV), making it difficult to be treated effectively, its treatment has entered a new era of personalized medicine since the discovery of oncogenic driver mutation. “At present, lung cancer is one of the most successful personalized treatment-based cancers among all cancer type. Therefore, the best and effective treatment for advanced lung cancer is to choose the right drug for the right person and target at the right timing,” explains Dr Lim.
You don’t have to wait till it’s too late to get a diagnosis though, especially if you are in the high-risk group. Data shows that low-dose computed tomography (LDCT) in those aged more than 55 year-old who have more than 30 pack-year history of smoking, or those aged more than 50 years-old who have more than 20 pack-year history of smoking with addition risks factors that increase lung cancer, picks up lung cancers earlier, thus reducing mortality. “LDCT has been shown to reduce the relative mortality of lung cancer by 20%, in the National Lung Screening Trial in United States,” says Dr Lim.
However, like many diseases, it pays to start early to reduce the risks of lung cancer, many of which you can take your own initiative to do so. If you’re smoking, make a concentrated effort to quit smoking. It can be hard for the first few months but after that, your lungs will thank you for it. Also, if you are surrounded by secondhand smoke, walk away – you have the right to not inhale it. With everything else, eat in moderation, exercise regularly, and go for regular health screenings if you’re in a high-risk group
http://www.moh.gov.my/moh/resources/Penerbitan/Laporan/Umum/Malaysian_Study_on_Cancer_Survival_MySCan_2018.pdf and https://lungcancer.net.my/Article_HCP/MNCR%202012-2016%20FINAL%20(PUBLISHED%202019).pdf