Cancer Treatment Centers of America

Diagnostic tools: Imaging 101

Author: Mia James

Diagnostic imaging can play a big role throughout all phases of the cancer journey. These tests and scans are used to make pictures of areas inside the body, which can help doctors identify and locate disease, guide certain treatment modalities, monitor treatment response, and spot recurrences during follow-up. Timothy McCay, DO, a radiologist at Cancer Treatment Centers of America® (CTCA) in Tulsa, Oklahoma, introduces us to some popular imaging tools and explains the roles that imaging can play in cancer treatment and beyond.

From diagnosis to recovery

For many patients an imaging test or scan is one of the first steps in treatment. “Typically, a patient who’s diagnosed with cancer goes to the doctor with a complaint, and then they’re referred to an imaging department to image that area of the body,” Dr. McCay explains.

Doctors may also incorporate imaging during treatment planning, as detailed information about a malignancy is necessary to determine appropriate therapy. For example, “Imaging may be utilized by a surgeon to determine if surgery would be the best option for a patient,” says Dr. McCay.

Following treatment, imaging can be used to determine if or to what extent therapy has been effective and to carefully monitor the patient for recurrence. “Imaging plays a very vital role in not only the diagnosis of cancer but also subsequent scans to determine if the cancer’s coming back, to what degree it’s coming back, or if it’s regressed,” Dr. McCay explains.

Imaging tools

The following imaging tools are commonly used in cancer treatment. The type of imaging you undergo will be determined by such factors as the nature and the location of the cancer or suspected cancer.

  • X-ray machines take images of the inside of the body, using highenergy electromagnetic radiation. X-rays may be used to diagnose and stage disease and also in radiation therapy to help destroy cancerous cells.
  • Ultrasound uses high-energy sound waves to create images of internal organs and tissues during diagnosis and staging and to locate a cancerous area for treatment. Ultrasound can also be used as part of a treatment to directly destroy cancerous cells.
  • Magnetic resonance imaging (MRI) uses radiofrequency waves, magnets, and a computer to take cross-sectional images inside the body. MRI can show the difference between normal and diseased tissue and is used in diagnosis and staging. The MRI scanner is a tube, which the patient passes through on a moving table.
  • Computed tomography (CT) is a type of X-ray that produces threedimensional, cross-sectional images. CT scans can be used in diagnosis and treatment to directly locate the cancer and show its size, and, during follow-up, to show whether treatment has been effective.
  • Positron emission tomography (PET) is a nuclear scanning technique that can be used in combination with a CT scan (PET/CT). Combined, these tests produce detailed information about a tumor’s location, growth, or spread.
  • Nuclear medicine imaging requires the ingestion of a radioactive substance (injected, inhaled, or taken as a pill). The substance, which gathers in the area of study and is visible with a nuclear scan, can reveal areas of cancer and monitor an organ’s function. Nuclear imaging scans include bone scans, multiplegated acquisition (MUGA) scans (to monitor heart function), and Miraluma breast imaging.

In the spotlight: PET and MRI

According to Dr. McCay, two scans are particularly noteworthy: PET and MRI. These techniques, he says, are likely to become increasingly used in cancer treatment.

“The PET scan is a tool that’s becoming increasingly utilized,” says Dr. McCay, explaining that because PET scans can measure the glucose metabolism of cells, which is higher in cancerous tissues, they are particularly useful in showing a cancer’s stage and whether it has recurred or regressed.

Dr. McCay also sees an expanding role for MRI in cancer treatment. For example, “We’ve learned that MRI has a higher resolution for liver lesions than CT does,” he says, which allows for earlier detection of disease that has spread to the liver. Dr. McCay also explains that MRI (as well as ultrasound) doesn’t emit radiation as do CT scans and X‑rays. “The more we can use MRI and ultrasound, the overall total dose of radiation to the patient is diminished.”

Three questions to ask your doctor about imaging

As with much of the cancer journey, educating yourself about imaging can help you make appropriate decisions and be more comfortable with the process. The following questions, says Dr. McCay, can help you prepare for scans and tests.

  • How soon can I have my tests done? If your current treatment facility can’t take care of you in a timely manner, consider another facility.
  • Which imaging studies are really necessary? In some circumstances one study may be sufficient.
  • What experience do you have with the recommended scan? For some scans provider experience affects accuracy and findings. Ask your health care team how familiar they are with the scan you’re undergoing.

Make imaging work for you

Your role in your treatment plan continues once you’ve undergone the scans, says Dr. McCay. He suggests that you stay proactive and involved by requesting scan results in a reasonable amount of time. “Remember that you’re the consumer,” he says.

After all, imaging is part of the treatment process, and like therapies and procedures, they’re done to help you get the best outcome possible. By understanding the studies you’ll undergo and their purpose, and by making sure you get results in a timely manner, you’re doing your part to ensure effective treatment.