An Introduction to Prostate Cancer Scans

Over recent years, prostate cancer imaging has played a vital role in improving the detection and diagnosis of prostate cancer. Imaging techniques can be used to facilitate the initial diagnosis of cancer by helping ensure that no areas have been missed out and guiding the placement and application of treatment in your body.

While the prostate-specific antigen (PSA) test is a very sensitive test for prostate cancer, it unfortunately cannot detect the exact location of your tumor, or determine whether your cancer has spread beyond your prostate.

The same goes for a physical examination of your prostate. This is where imaging plays its role — by offering a simple way to detect the primary lesion and its degree of spread, without subjecting you to an invasive biopsy procedure that requires anesthesia and time to recover.

A variety of imaging techniques are involved in the diagnosis and treatment of prostate cancer:

• Magnetic resonance imaging (MRI)

During an MRI, you will be placed in a large machine containing strong magnets. Radio waves will then be pulsed through your body, enabling the machine’s sensors to form an image of your prostate based on how it affects the magnetic field surrounding your body. Currently, the most accurate way of performing this exam is to use multiparametric MRI, which provides a more detailed image for improved precision and reliability.

If you are being considered for a prostate biopsy, the MRI can help guide the biopsy ensuring precise sampling of the tumor. In addition, it can also be used to determine your cancer stage by checking if there has been spread into the seminal vesicles or other organs.

• Transrectal ultrasound

This method is used to guide the placement of needles in biopsy and treatment procedures (e.g. brachytherapy). A finger-wide ultrasound probe will be coated with lubricant and inserted into your rectum, which may feel cold and cause a little pressure and discomfort. This probe will emit sound waves that will hit your prostate at different angles according to its shape. These waves will then echo back towards the probe, allowing it to record how your prostate looks like.

• Bone scan

If you are at high risk of prostate cancer metastasis, you may be recommended a bone scan for prostate cancer, as spread is usually seen in the bones first. You will be injected with a radioactive tracer, which will then target any areas of bone damage. This can then be detected by a camera to highlight potential cancer spread to the bone.

• Positron emission tomography (PET) scan

While MRI is the usual imaging technology for prostate cancer, the PET scan for prostate cancer is also good at identifying advanced spread and recurrence. One of the latest developments in this area is 68Ga-PSMA-11, another radioactive imaging tracer which is injected into the body, allowing it to bind to high levels of prostate-specific membrane antigen (PSMA) found in prostate cancer cells. These tracers are then detected by a camera to highlight where your cancer has spread.

You may be worried about the risk of radiation exposure from your prostate cancer scan. Notably, prostate MRI and ultrasound scans are free from damaging radiation and safe for most people.

While scans relying on radioactive tracers are generally safe, they can still increase your overall lifetime exposure to radiation. To minimize this, you can rest assured that your doctor will only suggest imaging tests when necessary.

At the end of the day, prostate scans remain crucial in the detection of prostate cancer. Still, it is important to discuss any concerns or pre-existing health conditions with your healthcare provider before undergoing any imaging procedure. They can provide personalized information based on your health history and the specific type of scan being considered. In many cases, the benefits of accurate diagnosis and medical information provided by these scans outweigh potential risks.

Additionally, the decision to undergo prostate scans should be made in consultation with your healthcare team, considering factors such as your age, overall health, and any symptoms or risk factors for prostate conditions. Regular communication with your healthcare provider ensures that the chosen imaging method is appropriate for your specific situation.