PET scans are a form of imaging scan that can take three-dimensional images of the inside of a person’s body. They can help a doctor detect and accurately stage someone’s liver cancer.

Doctors might combine PET scans with a CT scan to get a more detailed image of the specific area. If they combine these two scans, they may refer to it as a PET-CT scan.

Read on to find out more about the role of PET scans in liver cancer. This article looks at how PET scans work, what to expect from one, and more.

A person is getting a PET scan.Share on Pinterest
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PET or PET-CT scans can play a crucial role in the diagnosis and treatment of liver cancers such as hepatocellular carcinoma (HCC). HCC is one of the most common types of liver cancer, accounting for more than 90% of primary tumors of the liver.

PET-CT scans can help with:

  • detecting liver cancer
  • distinguishing which type of liver cancer a person may have
  • accurately identifying the stage of someone’s liver cancer

PET scans are usually for evaluating metastatic cancer — which refers to the spread of cancer cells to other parts of the body. Other imaging tests may be more suitable for taking a closer look at the primary tumor for potential surgery or involvement of critical structures.

A PET scan uses a radiotracer in the form of radioactive sugar. The body’s cells take in different amounts of the sugar, depending on how fast they are growing.

Cancer cells grow quickly, meaning they are more likely to take up larger amounts of the radiotracer.

A PET scan can detect areas where the radiotracer does and does not build up. This can help show how certain cells are functioning.

A healthcare professional administers the radiotracer in one of the following ways:

  • intravenously through a vein
  • orally
  • via inhalation

The radiotracer takes some time to make its way through a person’s body. The individual then slides through the central hole in the PET machine before the scan takes place.

When the radiotracers in a PET scan decay, they produce small particles called positrons, which react with electrons in the body. When they combine, they annihilate one another, producing a small amount of energy in the form of two photons.

The detectors in the PET scanner measure these photons, which they use to create images of inside a person’s body.

When preparing for a PET scan, a person may have to stop eating or drinking for 2–12 hours before the procedure.

An individual should also inform the doctor or nurse about any medications they are taking, including:

A person may have to avoid taking certain prescription or OTC medications for a period of time before the test. Their doctor will give them instructions regarding this.

Reactions to the radiotracer are very rare. However, it is best to inform a doctor about any allergies the person has and whether they have had previous reactions with nuclear medicine scans.

A PET scan will often take place in the radiology or nuclear medicine department of the hospital. A typical PET scan involves the following steps:

  • A person will need to remove all jewelry or metal items that could interfere with the scan. They may be able to wear their own clothes, though sometimes they may need to wear a gown during the test.
  • A doctor will begin by administering the radiotracer. They will most often do this intravenously using a needle.
  • The person will then need to wait for up to 1 hour for the tracer to make its way to the liver.
  • The PET scanner has a hole in the middle. A person will lie on a padded table that moves through the hole of the scanner.
  • A technician may ask the person to change positions to allow them to take scans of different views. Other than during those movements, an individual needs to remain still during the scan.

PET scans can take around 20–30 minutes.

A person can usually go home the same day as their PET scan. They should not experience any side effects after having the scan.

An individual’s specialist will usually receive their results and discuss them at their next appointment.

As a PET scan uses radioactive materials, there is a slight risk of radiation exposure.

However, the total radiation dose involved in a PET scan is no more than the amount of radiation exposure a person experiences in a routine chest X-ray or CT scan.

There may be concerns about how even low levels of radiation exposure can cause cancers. However, this risk is quite small, and the benefits that a PET scan can typically offer outweigh the risk.

When medical professionals make use of nuclear medicine, they help ensure radiation exposure is as low as possible. This includes giving the least amount of radiotracer necessary to provide an effective diagnostic image.

A doctor can use a PET scan to detect, distinguish, stage, and evaluate a person’s liver cancer.

A PET scan is a form of imaging scan that uses a radiotracer. This substance comprises carrier molecules that bond tightly to a radioactive atom.

PET scans can help create three-dimensional images of the inside of a person’s body. This can help show the location of the cancer as well as help evaluate the condition.