Imaging Tests for Cancer

Imaging tests, or radiology tests, take pictures of the inside of your body for your doctor’s review. These tests help find cancer, how far it has spread and whether your cancer treatment works for you.

What are imaging tests?

Imaging tests take pictures of the inside of your body by sending energy through it. This energy includes x-rays, sound waves, radioactive particles or magnetic fields, depending on the type of test. Your body tissues change the energy, creating an image. The images help your doctor and other professionals see your cancer and changes it causes.

Imaging tests provide information for your doctors. This information includes:

• Early detection of cancer or cancer screening
• Finding tumors
• Determining whether you need a biopsy
• Showing where tumors exist
• Staging your cancer according to its spread
• Planning treatment, such as for radiation
• Charting changes in your tumor after treatment
• Finding out if your cancer came back after treatment

Imaging tests make up part of your cancer diagnosis and treatment. They work with other types of tests and treatments for a full picture of your health. Tests commonly ordered with imaging studies include physical exams, blood work and other lab tests.

People with cancer usually undergo imaging tests like X-rays or CT scans before starting treatment. These images form a baseline upon which future images track changes.

Imaging Studies Are Not Foolproof

No tests exist without limits. Imaging studies have their limits, too. Imaging helps your treatment team find large cancer cell groups, for example. But they do not show cancer cells in low numbers. So even if your imaging tests look clear of cancer after treatment, your treatment may continue to get rid of any surviving cancer cells. After all, even one cancer cell can start a tumor. The goal of your treatment is to kill these problem cells before that tumor can begin.

Imaging tests also sometimes show abnormalities that look like cancer, but are proven wrong by other tests. This is why imaging tests rarely provide the only picture of your cancer to your treatment team.

Types of Imaging Tests

There are many different kinds of scans and imaging tests used for cancer. These include:

• Computed tomography (CT) scan
• Magnetic resonance imaging (MRI) scan
• Breast MRI
• X-rays and other radiographic tests
• Mammography
• Nuclear medicine scans
• Ultrasound

Your doctor orders imaging tests based on several factors, such as:

• Where your tumor is located and its type
• Whether he or she needs a biopsy
• Your overall health, age and gender
• Weighing of risks, side effects and benefits
• Your preference
• Test cost

When your doctor orders an imaging test, ask whatever question you need to ask to feel well-informed about this part of your cancer diagnosis and treatment. Some of these questions may include whether your insurance covers the imaging test, what risks or side effects potentially occur after undergoing the test and where your test will take place. Some tests require special preparation, such as fasting or use of radioactive materials or dyes. For any imaging study, talk to your treatment team for the most updated information and discussion of any expectations or available options.