Computed tomography (CT) scans have become an indispensable diagnostic tool in the healthcare industry ever since it was invented in 1967. Given its capabilities in providing detailed information about the human body's inner workings, it only made sense to improve it over the years as technology continued to improve.
One such improvement led to creating a new subset of CT scans called low-dose CT (LDCT) scans. Let us explore the key differences of this newer exam and the benefits it provides.
How do LDCT scans differ from regular ones? The most notable difference between LDCT scans and regular ones is in their radiation dosage. Since CT is a form of X-ray, it involves the use of ionising radiation. These X-rays make it possible to get a clear picture of the body's internals since they get absorbed by tissues as they pass through it, which the machine can then pick up and construct the picture results.
Although the radiation one can get from CT scans is not a lot higher when compared to the radiation received from space (typically when travelling by air) or naturally occurring materials like radon, any amount of exposure, no matter how small, increases the risk of future cancers.
LDCT scans address this concern by reducing the dosage of radiation used for the exam by as much as 5 times lower than a regular CT scan.
For comparison, an ordinary diagnostic CT scan provides radiation of about 7 millisieverts (mSv), the scientific unit of measurement for ionising radiation. In contrast, LDCT scans only have 1.4 mSv of radiation.
Who should get LDCT scans? Healthcare providers and lung cancer specialists in Singapore generally recommend LDCT scans as a lung cancer screening test. Because they are at high risk of lung cancer, patients should seek an LDCT annually with their physician if they are:
1. Aged between 50 and 80 years old
2. Presently smoking or quit smoking sometime within the past 15 years
3. Have a history of heavy smoking
While there is certainly a proven link between lung cancer and smoking, light smokers that quit the habit more than 15 years prior may not particularly benefit from this type of test. While it seems that those who are heavy smokers are the only ones who should look into getting LDCT scans, the fact is that the exam is also highly beneficial to those who have never picked up smoking.
During the International Association for the Study of Lung Cancer 2021 World Conference, researchers presented data findings that indicated the LDCT screening could also detect the presence of lung cancer in those who have never smoked any kind of tobacco product yet are still at high risk of the disease.
This distinction is pivotal since up to 20% of people who pass away due to lung cancer have not once smoked in their lifetime. Moreover, the fact is that lung cancer in such individuals have no known risk factors, which means they most likely will not take lung cancer screening tests early on since they do not believe they are at risk of it.
What are the benefits of LDCT scans? 1. Lower radiation exposure during exams The main difference between LDCT scans and regular ones － lower radiation exposure － is also one of its greatest benefits. By reducing the amount of radiation used while maintaining accuracy, patients are at less risk of developing potential issues caused by the exposure.
2. Does not require the consumption of contrast agents Regular CT scans will often require patients to take in dyes or contrast materials, liquids that better improve the image results of the scanner. LDCT scans can work without them while still providing the same level of detail and avoiding the potential mild side effects from consuming it, such as nausea.
3. Higher accuracy compared to regular CT scans When used to detect lung cancers, ordinary CT scans can identify nodules or potentially cancerous small growths in the lung, as small as the size of a dime. In contrast, LDCT scans can detect much smaller lung abnormalities similar to that of a grain of rice.
Conclusion Lung cancer and any other type of cancer can turn lethal if not addressed early on. Moreover, most patients with lung cancers are asymptomatic until it spreads. It’s rare for those with early-stage lung cancer to show any symptoms. (American Cancer Society, 2019). Because of this, the lung cancer is already at the advanced stage when the lung cancer is finally diagnosed for most cases.
With the improvements in LDCT scans, getting ahead of this disease has become much easier while also reducing the risk involved in radiation exposure.
If you are concerned about the dangers of cancer, our specialists here at ICS can ease your worries with our cancer diagnosis and treatment services in Singapore. By getting cancer-focused health screenings regularly, one can get some much-needed peace of mind and live their life to the fullest, knowing they are safe from such a disease.
1. Swedish Thoracic Surgery, Low-dose CT scan for lung cancer screening. Swedish. (n.d.). Retrieved November 2, 2021, from https://www.swedish.org/services/thoracic-surgery/our-services/lung-cancer-screening-program/low-dose-ct-scan-for-lung-cancer-screening.
2. Low-dose CT Scan. Cancer Treatment Centers of America. (2021, September 21). Retrieved November 2, 2021, from https://www.cancercenter.com/cancer-types/lung-cancer/diagnosis-and-detection/low-dose-ct-scan.
3. Ellis, P. M., & Vandermeer, R. (2011). Delays in the diagnosis of lung cancer. Journal of thoracic disease, 3(3), 183–188. https://doi.org/10.3978/j.issn.2072-1439.2011.01.01