Understanding a Prostate Cancer Diagnosis
A prostate cancer diagnosis can be confusing because prostate cancers vary greatly. Some grow so slowly that they may never cause problems, while others are more aggressive and require treatment.
Several pieces of information help determine how serious a prostate cancer is and what treatment, if any, may be appropriate. These include PSA level, biopsy results, Gleason score and Grade Group, MRI findings, and whether the cancer has spread beyond the prostate.
One of the most important things I learned is that a prostate cancer diagnosis does not necessarily mean treatment should begin immediately. For men with appropriate low-risk cancers, active surveillance may allow treatment to be safely postponed—or avoided altogether.
Understanding the specific characteristics of your cancer is therefore an important first step before deciding what to do.
What Determines the Risk?
Doctors consider several factors together when determining how serious prostate cancer may be.
PSA: Prostate-specific antigen is measured with a blood test. A higher PSA can be associated with prostate cancer, but PSA can also rise for other reasons, including an enlarged or inflamed prostate.
Biopsy and Grade Group: A biopsy shows whether cancer is present and how abnormal the cancer cells appear. The traditional Gleason score is now commonly accompanied by a Grade Group from 1 to 5, with higher numbers generally indicating more aggressive cancer.
MRI: Multiparametric MRI can help identify suspicious areas within the prostate, provide information about their location and extent, and help guide a biopsy.
Stage: Staging describes whether the cancer appears confined to the prostate, has grown into nearby tissues, or has spread elsewhere in the body.
Taken together, these findings help classify prostate cancer into risk groups and guide decisions about active surveillance or treatment.
Understanding the Gleason Score and Grade Group
The Gleason score describes how abnormal prostate cancer cells look under a microscope. A pathologist identifies the two most common patterns of cancer cells and assigns each a grade. The two grades are added together—for example, 3 + 4 = 7.
Importantly, 3 + 4 and 4 + 3 are not the same. A 3 + 4 cancer has more of the less aggressive pattern, while a 4 + 3 cancer has more of the more aggressive pattern.
A newer system called Grade Groups makes the results somewhat easier to understand:
Grade Group 1: Gleason 6 (3 + 3)
Grade Group 2: Gleason 7 (3 + 4)
Grade Group 3: Gleason 7 (4 + 3)
Grade Group 4: Gleason 8
Grade Group 5: Gleason 9–10
Generally, the higher the Grade Group, the greater the likelihood that the cancer will grow or spread.
The Decipher Score
The Decipher Prostate test is a genomic test performed on prostate cancer tissue obtained from a biopsy or surgery. It measures the activity of 22 genes and produces a score from 0 to 1 that provides additional information about how aggressive the cancer may be.
The score is classified as low, intermediate, or high genomic risk. It complements—not replaces—information such as PSA, Gleason score, Grade Group, stage, and MRI findings.
In some situations, Decipher can provide additional information when deciding between active surveillance and treatment or when considering whether additional treatment may be useful after surgery.
An advantage is that the test usually uses tissue that has already been collected, so another biopsy is generally not required.
Risk Groups
Doctors combine PSA level, Grade Group, tumor stage, biopsy findings, and sometimes imaging or genomic tests to estimate the risk that prostate cancer will grow or spread.
Prostate cancer is commonly described as low-risk, intermediate-risk, or high-risk. Intermediate-risk cancer may be further divided into favorable and unfavorable intermediate risk.
These distinctions matter because management can be very different. A man with low-risk prostate cancer may be a good candidate for active surveillance, while higher-risk cancer is more likely to require treatment.
The important point is that the words “prostate cancer” alone do not tell you how dangerous the cancer is. Understanding your individual risk category is one of the most important steps before making a treatment decision.
Questions to Ask Before Choosing Treatment
Before deciding on treatment, it can be helpful to ask:
What is my Grade Group and Gleason score?
What is my risk category?
Is the cancer confined to the prostate?
Do I need additional imaging, such as a PSMA PET scan?
Am I a candidate for active surveillance?
If treatment is recommended, what are the advantages and disadvantages of surgery, radiation, or other options?
What are the likely effects on urinary function, sexual function, and quality of life?
Should I get a second opinion before deciding?
Prostate cancer often allows time to understand the diagnosis, consider the alternatives, and make a well-informed decision.
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