ARE YOU AT RISK OF LUNG CANCER?
Lung cancer is often found in both women and men, with a mortality rate of more than 25%. For the 1st stage of lung cancer, the survival rate after 5 years is 68 – 92%. However, for the 4th stage, the survival rate after 5 year drops to only 5 – 10%. Therefore, lung cancer screening is of great importance, as it gives a better chance for timely treatment and full recovery if an early stage of the cancer is found. Today, a new technology called Low Dose CT Screening for Lung Cancer helps diagnosing the cancer accurately.
What Is Low Dose CT Screening for Lung Cancer?
Low Dose CT Screening for Lung Cancer is a technique by which a low dose radiation and computer tomography are used to produce an image of the chest and lungs.
Advantages of Low Dose CT Scan
Unlike the traditional chest X-rays which creates only a 2-dimentional picture, low dose CT scan produces a 3-dimrensional image that allows detection of lung cancer from an early stage.
- The amount of radiation is 5 – 6 times less than regular scans (low dose CT scan uses 1.4 mSv radiation, as compared to 7 mSv in normal scans.)
- It does not require any dye injection into the body.
- Takes only a short time, with only about 5 – 10 minutes on the CT scanner.
- There is no need to abstain from food and drink before the scan.
Who Should Receive Lung Cancer Screening?
The U.S. Preventative Services Taskforce (USPSTF), the group that provides guidelines for diseases prevention measures in the United States, recommends screening for people in the high-risk category, who are:
- 50 – 80 years of age, and
- Smoke ≥ 20 pack – year (number of years x number of packs per day), and
- Still smoke or quit less than 15 years.
Why Use Low Dose CT Scan?
A study on lung cancer screening among people in the high-risk group, comparing the results of chest X-rays against those of low dose CT scans, found that the latter detects early stages of the cancer more often than the former. This proved to have significantly reduced mortality rates.
How Often Should People in High-Risk Category Receive Low Dose CT Scanning?
Ideally, people in the high-risk group, if no lung cancer has already been discovered, should receive low dose CT scanning once a year. However, if any abnormality is detected, then they should be scanned again withing 1 – 6 months. Alternatively, they may choose to undergo additional X-rays or biopsies, depending on what the initial scans have revealed. It is highly recommended that they consult a specialist for further course of action.
Would A Non-Smoker Need Lung Cancer Screening Also?
For non-smokers who are in a high-risk category – for example, have a direct relative who has lung cancer, or have a history of lung diseases, live in an environment exposed to cancer-causing fumes (e.g., joss sticks smoke, and secondhand cigarette smoke) – there is a 0.4% chance that the low dose CT scan will discover they have lung cancer. This is generally found to be in an early stage of the cancer, which can be treated through a surgery and has a good chance of being completely cured. In any case, non-smokes in this category should consult a specialist about lung cancer screening.
Source: Dr. Thirada Vongvanichvathana,
Radiotherapist and Oncologist,
Wattanosoth Cancer Hospital