Prostate cancer is the second most common cancer in men worldwide. It can be challenging to diagnose early as it often shows no symptoms. However, early detection is crucial for successful treatment. Magnetic Resonance Imaging (MRI) is a non-invasive test that can help detect prostate cancer, guide biopsies, and investigate whether prostate cancer has spread. In this article, we will discuss how prostate cancer is diagnosed, the difference between normal MRI and MPM prostate MRI, and the various treatment options available.
How is prostate cancer diagnosed?
A prostate cancer diagnosis would normally consist of a combination of different tests. Examples of these include:
Prostate-Specific Antigen (PSA) Blood Test
The PSA blood test measures the amount of prostate-specific antigen in the blood. A raised PSA level can indicate an enlarged prostate or prostate cancer. If your PSA level is high, your doctor may recommend further tests.
Digital Rectal Examination (DRE)
During a DRE, a doctor will feel the prostate to check for any abnormalities. If the doctor suspects prostate cancer, they may recommend further testing.
Prostate Biopsy
A prostate biopsy involves taking small tissue samples from the prostate gland to test for cancer cells. The biopsy is taken with a thin needle, and sent to a lab for analysis. A prostate biopsy is the main method for diagnosing prostate cancer, but it may be combined with other examination methods such as MRI.
MRI for Prostate Cancer Diagnosis
MRI uses strong magnetic fields and radio waves to produce a detailed picture of the inside of the body. It is a non-invasive test that can check for abnormalites, and help plan whether a biopsy is necessary. It can also help determine the extent of how much the cancer cells have spread, and check the surrounding tissues, bones and lymph nodes.. Prostate MPM (multiparametric) is a special type of MRI specifically used for imaging of the prostate gland. Sometimes MRI is used to determine and guide where a biopsy should be taken from.
What is the difference between normal MRI and MPM prostate MRI?
A traditional MRI scan produces images of the prostate gland that help doctors determine whether prostate cancer is present. However, magnetic resonance spectroscopic imaging (MRSI) and magnetic resonance imaging (MRI) have been combined to produce an MRI scan that is highly sensitive to prostate cancer. This imaging technique is called multi-parametric MRI (MPMRI), and it can help doctors detect prostate cancer at an early stage.
The difference between a normal MRI and MPMRI is that MPMRI uses several imaging techniques to produce a more detailed picture of the prostate gland. These techniques include:
-
T2-weighted imaging: Produces images that show the structure of the prostate gland.
-
Diffusion-weighted imaging: Produces images that show the movement of water molecules in the prostate tissue, which can help detect cancerous areas.
-
Dynamic contrast-enhanced imaging: Uses a contrast agent to produce images that show the blood flow to the prostate gland.
The combination of these imaging techniques produces a highly detailed picture of the prostate gland, making it easier for doctors to detect cancerous areas. This can be especially helpful for men with elevated PSA levels, a family history of prostate cancer, or other risk factors.
Advantages of MPM Prostate MRI scans
Compared to a standard MRI, MPM prostate MRI has several advantages. Firstly, it can provide better visualisation and localisation of cancerous lesions in the prostate gland. Secondly, it can help identify early-stage prostate cancer that may not be visible on a standard MRI. Finally, MPM MRI can help guide targeted biopsies of suspicious areas in the prostate gland, which can improve the accuracy of prostate cancer diagnosis.
Disadvantages of MPM Prostate MRI scans
MPM prostate MRI does have some limitations. The technique is not always routinely available, and the cost of an MPM MRI scan may be higher than a standard MRI if accessed privately. However, the higher price tends to include a contrast agent and the range of techniques used in the study. Additionally, the interpretation of MPM MRI scans requires specialised training and expertise, which may not be available in all healthcare centres, though it is available via Scan.com.
When is MRI Used for Prostate Cancer Diagnosis?
MRI is typically used in diagnosing prostate cancer when:
-
The PSA (prostate-specific antigen) level is elevated in blood test results
-
The DRE (physical examination) suggests an abnormality
-
Previous biopsy samples suggest cancerous cells
-
A patient is on active surveillance
What are the Advantages of MRI in Prostate Cancer Diagnosis?
-
MRI can detect prostate cancer cells that may not be visible on ultrasound or CT scans.
-
MRI can provide a detailed picture of the prostate gland, allowing doctors to determine the extent of cancer spread.
-
MRI is non-invasive and does not require the use of radiation.
-
MRI can help doctors determine the best treatment options for patients.
What are the disadvantages of MRI in prostate cancer diagnosis?
-
MRI can produce false-positive or false-negative results, leading to further tests or missed diagnoses. Therefore, a combination of tests will usually be used to diagnose prostate cancer.
-
Prostate MPMRI requires the use of a contrast agent, which some people may be allergic to.
-
Patients with metal implants, shrapnel in their body, or medical devices such as cochlear implants and pacemakers may not be suitable for MRI due to a risk of the high-strength magnets interacting with metal in the body.
How accurate is MRI in diagnosing prostate cancer?
MRI's accuracy in detecting and diagnosing prostate cancer has seen promising research outcomes in recent years. In 2023, a study by University College London published in BMJ Oncology showed MRI to be significantly more effective at diagnosing early prostate cancer than the current blood test screening method. Of the men in the study who were found to have prostate cancer, over half had a 'normal' PSA rating. This means that without MRI, their cancer would have remained undetected by the UK screening programme and they would have been wrongly reassured that they were cancer-free.
In 2019, research conducted in Canada suggested MRI was effective 93% of the time when diagnosing prostate cancer, vs just 48% for biopsies. However, it is important to note that MRI alone is rarely used to diagnose prostate cancer - biopsies and additional tests as mentioned in this article are usually combined for the most thorough investigation and accurate diagnosis.
People who are concerned about their prostate health, have a family history of prostate cancer, or are experiencing symptoms should turn to MRI for accurate results. All MRI bookings via Scan.com include a pre-scan clinician consultation to make sure a Prostate MPM scan is suitable for you. But, if you're not sure whether or not to book, you can also book a phone consultation to discuss your concerns with an expert clinician, with no obligation to get a scan as a result.
What is the most accurate test to diagnose prostate cancer?
While the PSA test and DRE are commonly used to screen for prostate cancer, the most accurate test for prostate cancer is the prostate biopsy. However, this procedure can be uncomfortable, and it may miss small cancerous areas in the prostate gland. To increase the accuracy of prostate cancer diagnosis, doctors may also use imaging tests such as magnetic resonance imaging (MRI), transrectal ultrasound (TRUS), or computed tomography (CT) scans. In many cases, MRI can help prevent invasive biopsies in cases where no anomalies can be seen in the imaging results.
What do prostate cancer cells look like on an MRI scan?
Prostate cancer cells typically appear as dark areas on a T2-weighted MRI image. These dark areas indicate that the cancer cells are less dense than the surrounding healthy tissue.
In addition to T2-weighted images, other MRI sequences may also be used to help diagnose and stage prostate cancer. For example, a diffusion-weighted imaging (DWI) sequence can show how water molecules are moving within the prostate tissue, and areas of restricted diffusion may indicate the presence of cancer cells. A biopsy is normally required to definitively confirm cancer cells are present, and this can be guided by MRI scans.
It is important not to try and interpret your own MRI images without the expertise of a radiologist, who is a highly trained doctor specialising in the interpretation of diagnostic imaging tests. They will be able to help you understand what the images show, in simple terms that you can understand, and provide recommendations about what to do next.
Prostate cancer treatment
If prostate cancer is diagnosed, there are several treatment options available, including active surveillance, radiation therapy, surgery, hormone therapy, and chemotherapy. The choice of treatment will depend on several factors, such as the stage and grade of cancer, the patient's overall health, and the patient's preferences.
Active surveillance involves monitoring the cancer closely and treating it only if it grows or spreads. Radiation therapy uses high-energy radiation to kill cancer cells. Surgery involves removing the prostate gland and surrounding tissue. Hormone therapy involves blocking the hormones that fuel prostate cancer growth. Chemotherapy involves using drugs to kill cancer cells.
Conclusion:
Prostate cancer is a common disease that affects millions of men worldwide. MRI is a non-invasive imaging technique that can help diagnose and monitor prostate cancer. Standard MRI can detect suspicious areas in the prostate gland, but MPM MRI is a more advanced technique that provides better visualization and localization of cancerous lesions. MPM MRI can help guide targeted biopsies and improve the accuracy of prostate cancer diagnosis. However, MPM MRI is a relatively new technique that may not be widely available and requires specialized training and expertise for interpretation.
MRI is an accurate tool in diagnosing prostate cancer and is typically used when other tests indicate a potential problem. While it is not without its disadvantages, the benefits of MRI in detecting prostate cancer cannot be overstated. Early detection of prostate cancer can lead to successful treatment and increased survival rates. If you have any concerns about your prostate health, speak with your doctor about whether an MRI scan is right for you.
Next steps:
- If you have a concern about your prostate health or have been recommended a Prostate MPM MRI, you can book a scan today and get the results back quickly.
- Find out more about medical imaging by visiting our news page.
Sources used:
https://www.cancerresearchuk.org/about-cancer/prostate-cancer/getting-diagnosed/tests-for-prostate-cancer
https://www.cdc.gov/cancer/prostate/basic_info/diagnosis.htm
https://www.nhs.uk/conditions/prostate-cancer/diagnosis/
https://www.cancer.org/cancer/prostate-cancer/detection-diagnosis-staging/how-diagnosed.html
https://www.mayoclinic.org/diseases-conditions/prostate-cancer/diagnosis-treatment/drc-20353093
https://www.wcrf.org/cancer-trends/prostate-cancer-statistics/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8988779/
https://bmjoncology.bmj.com/content/2/1/e000057
