Can a CT Scan Find Cancer?

While it’s likely you’ve heard of “CT scans,” these imaging tests may not be the first piece of equipment you think of for finding cancer. Scanning for cancer usually involves an X-ray, ultrasound or MRI. But a CT scan shouldn’t be discounted, because it balances speed, detail and coverage — all features that make it a helpful tool for spotting a suspicious area in the body and guiding doctors toward next steps.

What Is a CT Scan?

CT stands for “computed tomography.” When you have one of these scans, you’ll lie on a table that moves through a scanning ring, which is shaped a bit like a doughnut. The CT scan uses X-rays to produce detailed, cross-sectional images of the body. (Think of a view of the body as if it were “sliced” to show its internal makeup — but this is not surgery and no cutting is involved.)

While CT scans are like standard X-ray tests, there’s an important difference. X-rays use a broad beam of radiation from only one angle. CT scans, on the other hand, have a pencil-thin beam that takes a series of pictures from different angles. The information from each of those angles is fed into a computer, which creates a black-and-white picture that’s like looking at a single slice from a loaf of bread.

Having a CT scan only takes a few minutes. After that, images from the scan are processed into clear, layered pictures that help doctors get a precise view of your organs, bones and tissues, showing these areas more clearly than standard X-rays.

Why Physicians Use CT Scans for Cancer Screening Instead of MRIs

CT scans help reveal suspicious masses or unusual growths in different parts of the body and are often faster and easier for patients. MRIs are also more costly, and their enclosed setting can cause some patients to feel claustrophobic. Additionally, because MRIs use a powerful magnet to create images, it isn’t the right device for people who have metals in their bodies, such as:

• Artificial heart valves
• Artificial joints
• Eye implants
• IUD
• Pacemakers
• Pins
• Plates

For people with any of these implants, CT scans offer a safe and comfortable alternative to MRI.

How a CT Scan Can Help with a Cancer Diagnosis

If you’re wondering if a CT scan can diagnose cancer, the answer is that it can certainly be part of the diagnostic process. CT scans offer a broad view of the body in just a few minutes, so they’re a vital tool for planning diagnosis and treatment. CT scans can:

• Find abnormal masses or tumors
• Show the size, shape and location of suspicious areas
• Uncover enlarged lymph nodes
• Help physicians see whether cancer may have spread (metastasized) to other organs
• Guide biopsies by showing where to select sample tissue
• Track the body’s response to treatment or check for return of the disease
• Detect these cancers:
  • Lungs
  • Pancreas
  • Liver
  • Colon
  • Kidneys
  • Brain
  • Ovaries and many others

CT scans can help reveal suspicious masses or abnormal growths in different parts of the body. They can show a tumor’s size, shape and bulk, which helps physicians decide if a growth is possibly cancerous. The scan can also help show how severe the cancer is and whether it has spread to other parts of the body. This helps a doctor decide on the most effective way to treat the disease.

What a CT Scan Can’t Do

A CT scan isn’t a defining test by itself. There are certain things the scan can’t do, so it can’t be the only way to confirm cancer. The scans may also miss small or early cancers, and they can’t always tell the difference between cancer and noncancerous conditions such as infections, inflammation or cysts.

If the CT scan shows anything unusual, your care team may recommend follow‑up tests, such as:

• Biopsy, which is the definitive way to diagnose cancer
• MRI, ultrasound or PET scan
• In some cases, blood tests or tumor markers

These additional tests ensure your care team has the full picture before deciding on the best path forward.

More to Know About CT Scans

CT scans use a small amount of ionizing radiation, a high-energy form of radiation. So, doctors tend to recommend CT scans only when the benefits outweigh the risks.

In some cases, a contrast dye is used to make specific blood vessels, tissue and abnormalities appear brighter and clearer. If you’re pregnant, breastfeeding or sensitive to iodine, seafood or contrast dye, you should let your physician know before having a CT scan.

Healing From Cancer Begins With Early Detection

Early detection is one of the most important steps to overcoming cancer. That's why we offer advanced screenings and diagnostic testing. Accurate and timely diagnoses can confirm the presence of cancer and provide essential information about the type, stage and characteristics.

Building a care plan tailored to your needs begins with the diagnostic methods we use to gather the right information about you. You’ll work with our team of oncologists, surgeons, counselors and wellness experts, who are dedicated to making your cancer treatment as comfortable and successful as possible.

Learn more about detection and treatment at AdventHealth.