Understanding your prostate MRI scans
The National Institute for Health and Care Excellence (NICE), the American Cancer Society (ACS) and the European Urology Association (EAU) all agree that multiparametric magnetic resonance imaging should be done when a patient presents with a high prostate-specific antigen (PSA). This will identify an enlarged prostate from cancerous tissue.
Magnetic resonance imaging has excellent diagnostic accuracy and tells the urologist if the cancer is localised in the prostate gland or has spread outside the prostate, invading seminal vesicles or if there is lymph node involvement.
The radiologist will interpret the prostate MRI using the PI-RADS system as its mainstay for prostate imaging reporting.
What does a PI-RADS score exactly mean?
The PI-RADS score is a system that grades the likelihood of clinically significant prostate cancer on a prostate MRI scan. The rating system ranges from 1 to 5, where each number corresponds to the possibility of prostate cancer.
The score is assigned based on an assessment of several characteristics of the prostate gland, such as the size, shape, and texture of any suspicious areas seen on the MRI scan. A radiologist reviews the images and assigns a PI-RADS score to each suspicious area before determining the final score.
A PI-RADS score of 1 or 2 suggests a low likelihood of prostate cancer, whereas a score of 3 indicates that the presence of clinically significant cancer is equivocal. A score of 4 or 5 suggests a high or very high likelihood of prostate cancer.
The PI-RADS score can help guide further diagnostic tests or determine the appropriate treatment options for prostate cancer, depending on the score and other factors such as the patient's age, overall health, and personal preferences.
It is important to note that a PI-RADS score is not a definitive diagnosis of prostate cancer but rather a tool used to help determine the likelihood of clinically significant cancer. The benefit of PI-RADs is they avoid an unnecessary prostate biopsy.
PI-RADS System Score Explained: To Biopsy or Not to Biopsy?
The decision to biopsy or not to biopsy depends on the PI-RADS score, the patient's overall health, and the patient's decision. If the PI-RADS score is high or very high, a biopsy may be recommended to confirm the presence of cancer. Conversely, if the PI-RADS score is low, the patient may be advised to have further monitoring without a biopsy.
According to the European Society of Urogenital Radiology (ESUR) guidelines,
PI RADs Scores Clinically Significant Prostate Cancer Risk
Pi rads 1 Very Low ~5%
Pi rads 2 Low ~10%
Pi rads 3 Intermediate ~35%
Pi rads 4 High ~50%
Pi rads 5 Very high ~70%
What other information can the multi-parametric MRI provide?
TNM stage
Apart from the T that looks to see if the cancer is localised or if it has spread outside the prostate, MRI prostate imaging looks at lymph nodes (N stage) and other organs (M stage)
Incidental findings
It is not uncommon that when MRI scans are performed, other changes unrelated to the prostate are picked up.
Understanding your prostate biopsy result
If my biopsy report mentions "core", what exactly does that indicate?
During a prostate biopsy, a small amount of tissue is obtained from the prostate gland using a biopsy needle. Each cylindrical sample of tissue obtained is known as a "core". Typically, multiple cores are taken from different prostate gland regions to increase the diagnosis's accuracy. The biopsy report will contain information regarding the number of cores obtained, their size, and any abnormalities detected in each core, including cancer cells, inflammation, or other abnormalities. This information is crucial in determining the appropriate treatment plan for the patient based on the diagnosis.
What does it mean when there are different core samples with different Gleason scores?
When different core samples from a prostate biopsy have varying Gleason scores, it may indicate the presence of mixed-grade prostate cancer. This means that the cancer cells in different areas of the prostate gland have varying levels of aggressiveness, leading to different Gleason scores in different core biopsy samples.
It's important to note that prostate cancer is frequently multifocal, which means that cancer cells can exist in various regions of the prostate gland. These cancer cells may have different grades of aggressiveness, causing differing Gleason scores across different core samples.
What is the Gleason grade or Gleason score? What do the numbers in the Gleason score mean?
The Gleason grade, or Gleason score, is a histopathological grading system that evaluates the aggressiveness of prostate cancer by examining the appearance of cancer cells under a microscope.
A Gleason score is determined by examining the biopsy or tissue sample under a microscope and assigning a grade based on the appearance of the cancer cells. The grade is based on two numbers, each ranging from 1 to 5, representing the most common and second most common patterns of cancer cells seen in the biopsy or tissue specimen. The sum of these two numbers determines the Gleason score, which ranges from 6 to 10.
A Gleason score of 6 is considered low-grade, meaning the cancer cells look more like normal prostate tissue and are less likely to grow and spread quickly. A score of 7 is intermediate-grade, meaning the cancer cells look less like normal prostate tissue and are more likely to grow and spread. Scores of 8 to 10 are considered high-grade, meaning the cancer cells look very different from normal prostate tissue and are most likely to grow and spread quickly.
The Gleason score is essential in determining prostate cancer's stage and aggressiveness. A higher Gleason score indicates a higher risk of cancer spreading beyond the prostate gland, which can significantly impact the recommended treatment approach. In addition to the Gleason score, other factors such as the patient's age, overall health, and cancer stage also play a role in treatment decisions.
What does Gleason grouping mean? How are they different from Gleason's score?
The Gleason score ranges from 6 to 10. It is determined by adding two numbers together, each representing the most common and second most common patterns of cancer cells seen in the biopsy or tissue specimen. The sum of these two numbers determines the Gleason score.
On the other hand, the Gleason grouping categorizes prostate cancer into one of five groups based on the Gleason score. The five Gleason groups are:
- Group 1: Gleason score 6 or less
- Group 2: Gleason score 3+4=7
- Group 3: Gleason score 4+3=7
- Group 4: Gleason score 8
- Group 5: Gleason score 9-10
Gleason grouping provides a more simplified and practical approach for clinicians to determine the aggressiveness of prostate cancer and to develop appropriate treatment plans for patients. Each Gleason group is associated with a different prognosis and treatment strategy.
It's important to note that the Gleason score and Gleason grouping are interrelated but not the same thing. The Gleason score determines the Gleason grouping, which then helps guide treatment decisions.
I have a Gleason score of 7 (3+4). How is this different from a Gleason score of 7 (4+3)?
A Gleason score of 7 (3+4) and a 7 (4+3) indicate intermediate-grade prostate cancer, but they differ in how the two numbers are arranged.
In a Gleason score of 7 (3+4), most cancer cells (at least 50%) have a grade of 3, and the remaining cancer cells have a grade of 4. This implies that cancer predominantly comprises less aggressive cancer cells, with some more aggressive cells.
In contrast, in a Gleason score of 7 (4+3), most cancer cells (at least 50%) have a grade of 4, and the remaining cancer cells have a grade of 3. This suggests that cancer mainly comprises more aggressive cancer cells, with some less aggressive cells present.
The order of the numbers in the Gleason score is crucial, as it reflects the aggressiveness of cancer and its likelihood of spreading outside the prostate gland. A Gleason score of 7 (4+3) may be associated with a higher risk of cancer spreading beyond the prostate gland than a Gleason score of 7 (3+4).
My Gleason score is 8. Is this serious?
A Gleason score of 8 is considered high-grade prostate cancer and a severe condition.
A Gleason score of 8 means that the cancer cells have a high degree of abnormality and are more likely to grow and spread aggressively beyond the prostate gland. Prostate cancer with a high Gleason score is often associated with a greater risk of recurrence after treatment and a higher likelihood of metastasis or spread of cancer to other parts of the body.
What is the risk of recurrence of prostate cancer after treatment?
Based on stage and Gleason's score, what is the risk of prostate cancer recurrence after radiotherapy?
Stage II prostate cancer recurrence risk
The risk of recurrence for patients with stage II prostate cancer who have received radiotherapy, based on their Gleason score:
- Gleason score 6: The risk of recurrence after radiotherapy is typically low, with around 10-15% of patients experiencing a recurrence within 5–10 years.
- Gleason score 7 (3+4): The risk of recurrence is somewhat higher than for Gleason score 6, with around 20–30% of patients experiencing a recurrence within 5–10 years.
- Gleason score 7 (4+3): The risk of recurrence is higher than for Gleason score 7 (3+4), with around 30–40% of patients experiencing a recurrence within 5–10 years.
- Gleason score 8–10: The risk of recurrence is highest for patients with a Gleason score of 8–10, with around 40–60% of patients experiencing a recurrence within 5–10 years.
Again, it's important to note that these percentages are based on general trends and may not apply to every case. The cancer's stage, the patient's general health, and the particular treatment strategy used can all impact the risk of recurrence.
Stage III prostate cancer recurrence risk
While there is no specific percentage of recurrence risk for each Gleason score in stage III prostate cancer after radiotherapy, studies have shown that patients with higher Gleason scores have a higher risk of recurrence.
One study found that patients with Gleason scores of 8-10 had a 5-year biochemical recurrence-free survival rate of approximately 50% after radiotherapy, while patients with Gleason scores of 6-7 had a 5-year biochemical recurrence-free survival rate of approximately 70%. However, it's important to note that these percentages can vary depending on the patient's case and other factors.
What is the risk of recurrence of prostate cancer after radical prostatectomy based on stage and Gleason score
Generally, a higher Gleason score and advanced stage are associated with a higher risk of recurrence. Here are some estimates of the risk of recurrence based on stage and Gleason score:
Stage II prostate cancer recurrence risk
- With a Gleason score of 6 or lower, the risk of recurrence is approximately 10%.
- With a Gleason score of 7, the risk of recurrence is approximately 30%.
- With a Gleason score of 8-10, the risk of recurrence is approximately 50%.
Stage III prostate cancer recurrence risk
- With any Gleason score, the risk of recurrence is approximately 70%.
What does it mean if, besides cancer, my biopsy report also says atypical glands, atypical small acinar proliferation (ASAP), glandular atypia, or atypical glandular proliferation?
In addition to prostate cancer, your biopsy report might say that you have atypical glands, atypical small acinar proliferation (ASAP), glandular atypia, or atypical glandular proliferation. In that case, it means that there are abnormal cells in your prostate gland that do not meet the criteria for a prostate cancer diagnosis but are not entirely normal.
These atypical cells may have some irregular features that are not typical of normal prostate gland cells but do not show the complete characteristics of cancer cells. If you have atypical glands, ASAP, glandular atypia, or atypical glandular proliferation, you have a greater chance of getting prostate cancer. However, not all cases of atypical findings will progress to cancer.
These unusual findings may need to be looked into and watched more closely because they could mean that closer monitoring or even more prostate biopsies are needed to confirm or rule out a diagnosis of prostate cancer.
Can the Gleason score on my biopsy tell the cancer grade in the entire prostate?
While the Gleason score obtained from a biopsy can provide valuable information about the aggressiveness of prostate cancer, it may not provide a complete picture of the cancer grade in the entire prostate. This is because the biopsy only samples a small portion of the prostate, and cancer may be present in other areas of the gland that were not sampled.
Additionally, prostate cancer is known to be multifocal, which means that multiple areas of cancer may exist in different parts of the prostate gland, and these areas may have different Gleason scores. As a result, the Gleason score obtained from the biopsy may not accurately represent the overall grade of the cancer.
To address these limitations, your doctor may recommend additional tests, such as imaging studies or additional biopsies, to better assess the extent and grade of cancer in the prostate. The Gleason score from the biopsy is just one factor considered when developing a treatment plan for prostate cancer.
What does it mean if, besides cancer, my biopsy report also says high-grade prostatic intraepithelial neoplasia or high-grade PIN?
Suppose your biopsy report mentions high-grade prostatic intraepithelial neoplasia (PIN). In that case, there are areas in your prostate gland where the cells that line the ducts and glands appear abnormal, and you may be at a high risk of developing cancer. However, it is essential to note that high-grade PIN is not cancer but a precancerous condition.
High-grade PIN is considered a risk factor for the development of prostate cancer, but not all men with high-grade PIN will develop cancer. However, men with high-grade PIN are more likely to develop prostate cancer than men without this condition.
Your doctor will likely monitor you closely if you have a high-grade PIN and may recommend additional testing or biopsies to check for the presence of cancer.
My biopsies show acute inflammation (acute prostatitis) or chronic inflammation (chronic prostatitis) should I worry?
If your biopsy report mentions acute or chronic inflammation, your prostate gland is experiencing an inflammatory response. Acute inflammation, also known as acute prostatitis, is an infection-related, sudden onset of inflammation in the prostate gland. Infection may or may not cause chronic inflammation, also called chronic prostatitis, a long-term prostate gland inflammation.
Inflammation in the prostate gland can cause various symptoms, including pain or discomfort in the groin or pelvic area, painful urination, difficulty urinating, and blood in the urine. However, some men with inflammation may not experience any symptoms at all.
While inflammation in the prostate gland does not necessarily mean that you have prostate cancer, it can make it more challenging to interpret biopsy results. Inflammation can cause changes in the appearance of the prostate gland and may make it more challenging to detect cancer cells.
Reflection from a prostate cancer specialist
The improved image quality of prostate MRI scans has revolutionised how urologists decide and perform prostate biopsies. The prostate imaging reporting and data system (PI-RADS) have been proven to relate to the grade group. This has helped urologists better identify clinically significant (high-grade) cancer and avoid unnecessary biopsies.
The MRI scan has also proven its role in active surveillance, which is one of the treatment options for the early detection of low-risk (lowest Gleason score) prostate cancer.
The combination of prostate imaging and prostate biopsy reports is crucial in choosing the best treatment options.
