CT Scan for Liver Cancer Detection

Liver cancer, particularly hepatocellular carcinoma (HCC), is a significant global health concern, ranking as the sixth most common cancer and the fourth leading cause of cancer-related deaths worldwide. Early detection improves treatment outcomes and patient survival. Imaging techniques, especially CT scans, play an important role in liver cancer diagnosis. 

CT scans provide detailed, noninvasive visualization of the liver and surrounding structures. They offer high diagnostic accuracy for detecting liver tumors and lesions. CT scans are particularly valuable for screening high-risk individuals, aiding in cancer staging, treatment planning, and guiding procedures like biopsies. 

What is a CT Scan?

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 body¹. 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 tissues². 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 gantry³. 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.

How CT Scans Detect Liver Cancer

CT scans play an important role in detecting liver cancer by providing detailed, cross-sectional images of the liver and surrounding tissues. These scans use X-rays and computer processing to create high-resolution images that can reveal tumors, lesions, and other abnormalities within the liver.

A contrast agent is typically injected into the patient’s vein to visualize all the structures in the liver. This iodine-based dye enhances the visibility of blood vessels and tissues, making tumors more apparent⁴. Radiologists can observe how it moves through the liver’s blood vessels, highlighting abnormal areas that might indicate cancer.

Signs of liver cancer on a CT scan might include:

1. Hypervascular lesions: Liver tumors often appear as areas of increased blood flow during the arterial phase of the scan⁵.
2. Washout: In later phases, cancerous lesions may show rapid loss of contrast compared to surrounding liver tissue⁶.
3. Tumor size and location: CT scans can accurately measure the size and pinpoint the exact location of liver tumors.
4. Mosaic architecture: Some hepatocellular carcinomas (HCCs) may display a characteristic mosaic pattern⁷. This pattern can look like a patchwork quilt, with different areas of the tumor showing varying colors and textures, reflecting the mix of healthy, cancerous, and damaged tissues within the tumor.
5. Nodule-in-nodule appearance: This feature can indicate HCC. It appears as a smaller spot within a larger spot, often indicating that a cancerous growth is developing within a preexisting, less harmful liver lesion⁸.

Contrast-enhanced CT scans significantly improve liver cancer detection. Dynamic multiphase contrast-enhanced CT is considered to be a standard for diagnosing HCC⁹. This technique involves taking multiple images at different time points after contrast injection¹⁰.

‍Arterial phase: Captures early enhancement of hypervascular tumors.

‍Portal venous phase: Shows contrast distribution throughout the liver.

‍Delayed phase: Can reveal washout characteristics of malignant lesions.

These phases allow radiologists to observe the dynamic behavior of liver lesions, which is crucial for accurate diagnosis. The American College of Radiology's LI-RADS (Liver Imaging Reporting and Data System) classification uses these imaging characteristics to categorize liver lesions and determine their likelihood of being HCC¹¹.

While CT scans are highly effective in detecting liver cancer, very small lesions (less than 1 cm) may be missed¹². Therefore, CT scans are often used in conjunction with other imaging modalities like MRI, ultrasound, and blood tests for comprehensive liver cancer diagnosis and staging¹³.

Benefits of Early Detection with CT Scans

Early detection of liver cancer significantly improves patient outcomes and survival rates. Patients with very early-stage hepatocellular carcinoma (HCC) can achieve 5-year survival rates of 70 - 80 percent after treatments like surgical resection or liver transplantation^14,15. This is a stark contrast to the overall 5-year net survival rate for liver cancer, which is only about 22 percent¹⁶.

CT scans play an important role in the early detection and accurate staging of liver cancer. They have a sensitivity of 77.5 percent and a specificity of 91.3 percent for detecting HCCs of any size and stage¹⁷. CT is highly accurate in identifying the number of lesions, affected liver segments, regional lymph node involvement, and vascular tumor invasion¹⁸. This precise staging information allows doctors to determine the best treatment approach.

CT scans can also detect small tumors. For tumors between 10-20 mm, CT scans have a sensitivity of 84 percent, allowing medical practitioners to catch liver cancers at their earliest stages. CT surveillance is associated with significant improvements in early tumor detection, providing curative therapy, and overall survival in patients with cirrhosis¹⁴.

Who Should Get a CT Scan for Liver Cancer?

You might be recommended to get a CT scan if you have specific risk factors or symptoms that suggest a higher likelihood of developing liver cancer. 

1. Individuals with chronic liver disease: People with cirrhosis, regardless of age, should undergo regular liver cancer screening, including CT scans¹⁹.
2. Chronic hepatitis B or C carriers: Those with long-term hepatitis B or C infections are at increased risk of developing liver cancer and should be screened regularly²⁰.
3. Family history of liver cancer: Individuals with a first-degree relative (parent, sibling, or child) who had liver cancer have about a four times higher risk of developing the disease, even without viral hepatitis²¹.
4. High-risk groups: Asian and Pacific Islanders and African men have a higher incidence of chronic hepatitis B infections and liver cancer. They may need to start screening at an earlier age^22,23.
5. People with specific conditions: Those with hereditary hemochromatosis, nonalcoholic fatty liver disease, or diabetes have an increased risk of liver cancer²⁴.
6. People with multiple risk factors: People who have a combination of risk factors, such as chronic hepatitis infection and a family history of liver cancer, are at particularly high risk and should be screened regularly.

Symptoms that could prompt a CT scan include²⁵:

• Unexplained weight loss
• Loss of appetite
• Abdominal pain or swelling
• Jaundice (yellowing of the skin and eyes)
• Fatigue

It’s important to note that early-stage liver cancer often doesn’t cause symptoms, which is why regular screening for high-risk individuals is imperative.

If you are a high-risk individual, there are several recommendations you should consider²⁶:

• Men with chronic hepatitis B should start liver cancer screening at age 40, while women should start at age 50.
• African men with chronic hepatitis B should begin screening at age 20.
• Patients on a liver transplant waiting list should be screened regularly.
• Individuals with cirrhosis should undergo regular screening regardless of age.
• Those with a family history of liver cancer should discuss early and more frequent screening with their healthcare provider.

How Much Does a CT Scan for Liver Cancer Cost?

The cost of a CT scan for liver cancer in the United States can vary but typically ranges from $464 to $1,061^27,28. However, the total cost of liver cancer screening, which may include multiple tests over time, can be much higher. The average lifetime cost of liver cancer screening is estimated to be between $6,400 and $8,600 per person.

Insurance coverage for CT scans used for liver cancer detection is generally good. Medicare usually covers most cancer screening tests, including CT scans for liver cancer, often with little to no out-of-pocket cost²⁹. Private insurance plans are required by the Affordable Care Act (ACA) to cover certain cancer screening tests, though coverage may vary depending on the specific plan. For those with Medicare Advantage plans, CT scans are typically covered, but costs may vary depending on the specific plan³⁰. 

‍Ezra offers comprehensive full-body MRI scans that cover multiple organs, including the liver. Their advanced scanning technology can screen for potential cancer and over 500 conditions in up to 13 organs. Ezra accepts FSA/HSA dollars and provides flexible payment plans.

Frequently Asked Questions

How much radiation am I exposed to With a CT scan?

Ionizing radiation from medical imaging, particularly CT scans, poses potential health risks by damaging living tissues at the atomic level. This damage can potentially increase cancer risk over time³¹. Low-dose CT (LDCT) scans have been developed to address these concerns as a safer alternative for routine screenings.

LDCT scans use substantially less radiation than standard CT scans, making them more suitable for frequently monitoring conditions. A standard CT scan of the abdomen, which includes the liver, typically delivers an effective dose of about 5-10 mSv (millisieverts). A CT scan of the abdomen and pelvis can deliver up to 15.4 mSv, which is equivalent to about five years of background radiation exposure³².

In contrast, LDCT scans use significantly less radiation. An LDCT of the chest delivers about 1.4 mSv, equivalent to about 6 months of background radiation³³.

How should I prepare for a liver CT scan?

You might need to fast for several hours before your appointment for a liver CT scan procedure³⁴. Clear fluids and medications are usually allowed³². Diabetic patients can have a light snack if necessary. You should wear comfortable, loose-fitting clothing to your appointment and will likely be given a hospital gown for the scan. You should remove any metal items, including jewelry, from the scanned area. 

For liver CT scans, you might need a contrast-enhanced scan. An IV line may be placed, or you might be given an oral contrast to drink³⁵. You should inform your healthcare provider about allergies, especially to iodine or contrast materials.

You should also inform your doctor if you are or might be pregnant. Also, disclose any medical conditions, recent illnesses, or medications you take. For example, if you’re taking metformin for diabetes, you may need to temporarily stop this medication³⁶.

Conclusion

CT scans play a vital role in detecting liver cancer at an early stage, significantly improving treatment options and patient outcomes. Their ability to generate detailed, high-resolution images aids in identifying tumors and lesions, making them indispensable for accurate staging. Contrast agents enhance visibility, ensuring even subtle abnormalities are detected. For individuals in high-risk groups or experiencing potential symptoms, consulting a healthcare provider is essential for timely screening and diagnosis. Early detection through CT scanning can improve overall survival and is an essential part of the liver cancer diagnosis process, alongside MRI and ultrasound.

If you want to be proactive about your health, why not book an Ezra Full-Body Plus? We combine MRI with LDCT to catch potential cancer earlier, leveraging AI through the screening process to make it more efficient, affordable, and faster.