Lung cancer is the leading cause of cancer-related deaths globally, with 1.8 million deaths reported in 20201. Low-dose computed tomography (LDCT) scans have emerged as a powerful tool for lung cancer screening. Early diagnosis of lung cancer is key to improving survival rates, with people diagnosed at the earliest stages being nearly 20 times more likely to survive for five years than those whose cancer is detected late2.
A computed tomography (CT) scan is a diagnostic imaging procedure that uses X-ray technology and computer processing to create detailed cross-sectional images of the body3. It produces more detailed images than standard X-rays, allowing healthcare professionals to visualize internal structures such as bones, muscles, organs, and blood vessels.
CT scans are advanced medical imaging techniques that use X-rays and computer processing to create detailed cross-sectional images of the body. The technology involves a rotating X-ray tube and detectors that measure X-ray attenuation through different tissues4. These measurements are then processed using tomographic reconstruction algorithms to produce virtual “slices” of the body.
The CT machine consists of a motorized table that moves the patient through a circular opening called the gantry5. Inside the gantry, an X-ray source and detector assembly rotate around the patient, typically completing a rotation in less than a second. As the X-rays pass through the body, detectors register the radiation that emerges, creating snapshots from various angles. The computer then reconstructs these snapshots into cross-sectional images or slices of the internal organs and tissues.
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LDCT and regular CT scans are used in lung cancer detection, but they differ in several key aspects.
- Radiation Exposure
LDCT scans use approximately 90 percent less radiation than standard CT scans (from 7 mSv to 2 mSv ionizing radiation)6. Reducing radiation exposure makes LDCT safer for routine screening and annual examinations, minimizing the long-term risks associated with repeated imaging.
- Image Quality and Detection Capability
Despite the lower radiation dose, LDCT scans maintain high image quality for lung cancer screening:
- Screening Effectiveness
LDCT has proven to be more effective for lung cancer screening compared to traditional chest X-rays.
CT scans detect signs of lung cancer by providing detailed cross-sectional images of the lungs. This technique offers several advantages for identifying abnormalities and staging lung cancers.
After CT images are captured, radiologists examine the images, looking for subtle and significant changes in lung structure. They can identify various abnormalities, including lung nodules as small as a few millimeters, suspicious masses, areas of tissue density changes, and potential signs of cancerous growth11. The exceptional detail provided by CT scans allows medical professionals to detect lung abnormalities at much earlier stages than traditional chest X-rays.
Early detection of lung cancer is critically important in improving patient survival rates and treatment outcomes. When lung cancer is identified at its earliest stages, patients have significantly higher chances of successful treatment and long-term survival. LDCT screening has demonstrated remarkable effectiveness, showing a 20 percent reduction in lung cancer mortality compared to conventional chest X-rays12.
Lung cancer manifests on CT scans through various distinctive visual characteristics. Malignant growths typically appear as solid nodules - dense, round, or irregularly shaped masses within lung tissue13. Some cancers present as ground-glass opacities, which appear as hazy areas that might indicate early-stage adenocarcinoma14. More advanced cancers often display spiculated masses with irregular, spiked edges, which are strong indicators of potential malignancy15.
CT scans are crucial in lung cancer staging, providing detailed information about tumor characteristics and potential spread. The staging process involves assessing three key components: tumor size and location (T), lymph node involvement (N), and potential metastasis (M)16. While CT scans are excellent for determining tumor size and initial location, additional imaging like PET-CT might be used to confirm lymph node and metastatic involvement.
LDCT scans offer significant advantages for lung cancer screening in high-risk patients:
The US Preventive Services Task Force recommends annual LDCT screening for individuals who meet the following criteria19:
The American Cancer Society has similar guidelines, recommending yearly LDCT screening for people aged 50 to 80 years who meet the smoking history criteria20. However, screening should be discontinued once a person has not smoked for 15 years or develops a health problem that substantially limits life expectancy or the ability to undergo curative lung surgery.
For some CT scans, you may need to fast for four hours before your appointment21. During this time, you can drink clear fluids and take your usual medications22. Diabetic patients may have a light snack if necessary but should avoid heavy meals. If your scan requires contrast material, you may be asked to drink water or a specific liquid contrast before the procedure.
You’ll likely need to change into a hospital gown and remove any metal objects, such as jewelry, from the scanned area. Wearing loose, comfortable clothing to your appointment is recommended.
If contrast is required, an IV may be placed in your arm or hand to administer the contrast dye23. In some cases, you may need to drink an oral contrast to enhance the visibility of your digestive system. Before receiving contrast, let your healthcare provider know if you have allergies, particularly to iodine or contrast agents.
At Ezra, we don't use contrast dye in our CT scans. This means you can relax, knowing that you won’t need to worry about any additional preparation.
If you’re pregnant or think you might be, inform your doctor. Additionally, share any medical conditions, recent illnesses, or medications you’re taking. Diabetic patients on metformin may be advised to temporarily stop this medication24.
A CT scan is a quick, non-invasive imaging procedure that produces detailed images of internal structures.
The entire process typically takes 15 to 30 minutes, with the actual scanning lasting about 10 to 15 minutes. You’ll lie on a table that slides through the CT scanner, which resembles a large doughnut. The radiographer will operate the scanner from a separate room but will communicate with you via an intercom. You may hear whirring or buzzing sounds as the X-ray machine rotates around you. At certain moments, you may be asked to hold your breath briefly to ensure clear images.
If you feel anxious, inform the radiographer, who can provide guidance to help you stay calm. For those prone to claustrophobia, it’s worth noting that the CT scanner does not completely enclose your body, reducing the likelihood of feeling confined.
CT scans are safe and use low levels of radiation25. The procedure is painless, though lying still for the duration may cause minor discomfort. Radiographers prioritize your safety and comfort throughout the process, so feel free to voice any concerns.
While CT scans are generally safe, it’s essential to be aware of potential risks and precautions.
CT scans use ionizing radiation, which can potentially damage living tissues by removing electrons from atoms, posing a slight risk of cancer over time26. To minimize these risks, LDCT scans are available. These scans use significantly less radiation and are especially beneficial for routine screenings, such as lung cancer monitoring.
Contrast agents are sometimes used to enhance imaging clarity. However, they may not be suitable for patients with allergies to contrast materials or kidney issues27. In such cases, alternative imaging techniques like ultrasound or MRI can be explored. Non-contrast imaging protocols may also provide adequate diagnostic information.
Ezra doesn’t use contrast agents in their LDCT scans. This approach has several advantages:
By focusing on these non-contrast methods, Ezra can provide high-quality diagnostic images while prioritizing patient safety and comfort.
Lung cancer screenings are most beneficial for individuals with higher risk:
The cost of a standard chest CT scan varies widely across major US cities. Prices can range from $350 to $5,400, depending on the location:
At Ezra, we offer a fixed-price alternative with our Full Body Plus scan. This scan includes a low-dose chest CT and a full-body MRI scan. Available at all Ezra Partner Facilities, this comprehensive screening option provides consistent pricing and a more predictable and cost-effective choice for individuals seeking extensive health evaluations.
CT scans are highly accurate for detecting lung cancer. The diagnostic accuracy is approximately 93-95 percent, with a recent study finding that mult-detector CT (MDCT) had a sensitivity of 97.5 percent and specificity of 85 percent for lung cancer detection30.
While CT scans are highly accurate, they can occasionally miss lung cancer. False-negative results can occur, though they are relatively uncommon. In some screening programs, false-negative cases may constitute up to 15 percent of all lung cancers diagnosed31.
CT scans, particularly LDCT, are invaluable tools for the early detection and management of lung cancer. By providing detailed cross-sectional images, LDCT allows for identifying lung abnormalities at their earliest stages, significantly improving survival rates. With reduced radiation exposure, LDCT is a safer option for routine screenings in high-risk populations. LDCT offers a promising pathway for improving early lung cancer diagnosis, improving patient outcomes, and reducing lung cancer mortality while prioritizing safety and accessibility.
If you want to be proactive about your health, why not book an Ezra Full-Body Plus scan? We combine MRI with LDCT to catch potential cancer earlier, leveraging AI through the screening process to make it more efficient, affordable, and faster.
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