Your Gleason score is a number between 6 and 10 that tells you how aggressive your prostate cancer is and what treatment options make sense for your situation. After a prostate biopsy, a pathologist examines tissue samples under a microscope and assigns grades based on how abnormal the cancer cells look compared to healthy prostate cells. These two grades are added together to create your Gleason score, which becomes the foundation for your entire treatment plan .

What Does Your Gleason Score Actually Mean?

Think of your Gleason score as a speed indicator for your cancer. A score of 6 means your cancer is slow-growing and unlikely to spread, while a score of 10 represents the most aggressive form of prostate cancer with the highest chance of spreading beyond the prostate . The scoring system works because cancer cells that look more abnormal under the microscope tend to behave more aggressively in your body.

Here's what each score range tells you about your cancer's behavior:

• Gleason 6 (Grade Group 1): Cancer cells look similar to normal prostate cells and grow slowly or not at all, making it the least aggressive type
• Gleason 7 (Grade Groups 2 and 3): A mix of normal and abnormal cells with intermediate risk; 3+4 is considered favorable intermediate risk while 4+3 is unfavorable intermediate risk
• Gleason 8 (Grade Group 4): Most cells look abnormal and may grow at a moderate to quick pace
• Gleason 9 or 10 (Grade Group 5): Most or all cells appear abnormal with the highest likelihood of rapid growth and spread

Many hospitals now use both the traditional Gleason score and a simplified Grade Group system (1 through 5) to help patients better understand their diagnosis. The Grade Group approach makes it easier to compare your cancer's aggressiveness without getting lost in the number combinations .

How Does Your Gleason Score Guide Treatment Decisions?

Your Gleason score is the primary tool doctors use to predict how quickly your cancer will grow and to select the best treatment approach for you. Prostate cancer in general grows slowly compared to other cancers, so even a Gleason 6 is a slow-growing version of an already slow-growing disease .

"Historically, when we thought about treating solid tumors, the first expected treatment was to have surgery to remove the tumor. Now, we are seeing treatment more frequently with targeted medication before surgery," said Dr. Judy C. Boughey, chair of the Division of Breast and Melanoma Surgical Oncology at Mayo Clinic in Rochester, Minnesota.

Dr. Judy C. Boughey, Chair of the Division of Breast and Melanoma Surgical Oncology at Mayo Clinic in Rochester, Minnesota

For low-risk cancers (Gleason 6), doctors typically recommend active surveillance rather than immediate surgery or radiation. This means regular monitoring with PSA (prostate-specific antigen) blood tests, digital rectal exams, MRIs, or repeat biopsies to catch any changes early. If your doctor notices concerning changes, treatment can begin at that point .

Intermediate-risk cancers (Gleason 7) offer more flexibility. If your score is 3+4, you might choose active surveillance, surgery, radiation, or focal therapy options like cryoablation or high-intensity focused ultrasound (HIFU). However, if your score is 4+3, treatment is usually recommended because the cancer has more abnormal cells .

High-risk cancers (Gleason 8, 9, or 10) almost always require treatment because they grow faster and have a higher chance of spreading beyond the prostate. The good news is that while metastatic prostate cancer cannot be cured, it is treatable with hormone therapy, chemotherapy, or radiation therapy .

How to Work With Your Doctor After a Gleason Score Diagnosis

• Ask for clarification: Request that your doctor explain your specific Gleason score and Grade Group in plain language, and ask what each number means for your individual situation
• Discuss PSA levels: Understand that your prostate-specific antigen (PSA) level at diagnosis, combined with your Gleason score and cancer stage, helps predict your risk of serious outcomes
• Take time for decisions: Even with high-risk prostate cancer, you typically have several months between diagnosis and when treatment must begin, giving you time to discuss options with loved ones and your care team
• Consider a second opinion: Because treatment options vary based on your specific Gleason score and Grade Group, getting input from another oncologist can help you feel confident in your choice

Recent data shows that treatment approaches for prostate cancer are evolving. In 2022, roughly 60% of men with prostate cancer were treated with non-surgical options like medication or radiation, up from 54% in 2018 . This shift reflects growing recognition that not all prostate cancers require surgery, and that medication given before surgery can sometimes shrink tumors enough to allow less invasive procedures .

Your Gleason score is not a death sentence; it's a tool that helps your medical team create a personalized plan. The most common type of prostate cancer diagnosed is Gleason 6, which is slow-growing and often managed with careful monitoring rather than aggressive treatment. Understanding what your score means empowers you to have informed conversations with your doctor and make decisions that align with your values and health goals.