If you or someone you love has had a prostate biopsy, the Gleason score is one of the first numbers you’ll hear. It can sound alarming. Here’s what it actually measures, how the newer grade groups work, and how doctors use it with other tests to plan treatment.
Key takeaways
- The Gleason score adds the two most common grades seen in prostate cancer cells under a microscope, and most cancers score 6 or 7.
- Grade groups 1 to 5 sort the scores: group 1 (6 or less) is slowest-growing, and group 5 (9 or 10) is most likely to grow fast.
- The score is one part of the picture, along with your PSA test, the cancer’s stage, your health and your wishes.
What is a Gleason score?
A Gleason score describes how abnormal prostate cancer cells look under a microscope. A pathologist grades the two most common patterns and adds them together. Lower scores mean slower-growing cancer, and higher scores mean cancer that’s more likely to grow and spread. Most prostate cancers score 6 or 7, according to MedlinePlus.
How the Gleason score is worked out
After a biopsy, a pathologist looks at the cancer cells and gives each pattern a grade from 1 to 5, based on how abnormal the cells look, MedlinePlus explains. The two most common grades are added together. The lowest grade given to a tumor is 3, so in practice scores run from 6 to 10.
For example, if the most common pattern is grade 3 and the second most common is grade 4, the score is 3 + 4 = 7. The National Cancer Institute says the higher the score, the more likely the cancer is to grow and spread quickly.
Gleason score and grade groups
Doctors now also use grade groups, which sort Gleason scores into five steps. MedlinePlus lists them like this:
| Grade group | Gleason score | What it means |
|---|---|---|
| Grade group 1 | 6 or lower | Low grade, slow-growing |
| Grade group 2 | 3 + 4 = 7 | Medium grade |
| Grade group 3 | 4 + 3 = 7 | Medium grade, with more abnormal cells than group 2 |
| Grade group 4 | 8 | High grade |
| Grade group 5 | 9 or 10 | High grade, most likely to grow fast |
MedlinePlus says a lower group suggests a better chance of successful treatment, and a higher group means more of the cancer cells look different from normal cells.
Gleason score 7: 3+4 vs 4+3
Both add up to 7, but they aren’t the same. The first number is the most common pattern. In 3 + 4, most of the cancer is grade 3, so it’s grade group 2. In 4 + 3, most of it is the more abnormal grade 4, so it’s grade group 3. That difference can affect which treatments your doctor suggests.
How the score guides treatment
MedlinePlus says grading helps you and your doctor choose treatment, together with the cancer’s stage, your PSA test result, your overall health and your own preferences. PSA is a substance made by the prostate that can be higher in the blood of men with prostate cancer, the NCI explains.
Not every prostate cancer needs treatment right away. The NCI describes active surveillance, which means closely following the cancer without treatment unless test results change, and watchful waiting, which means monitoring until symptoms appear or change. Your care team will explain whether these fit your situation.
Prostate cancer symptoms
The CDC says most prostate cancers don’t cause symptoms early on. See your doctor right away if you have:
- difficulty starting to urinate, or a weak or interrupted flow
- peeing often, especially at night
- trouble emptying your bladder completely
- pain or burning when you pee
- blood in your urine or semen
- pain in the back, hips or pelvis that doesn’t go away
- painful ejaculation
Should you get screened?
The main screening test is the PSA blood test. The CDC shares the US Preventive Services Task Force advice: men aged 55 to 69 should make their own decision about PSA screening, and men 70 and older shouldn’t be screened routinely. Talk to your doctor about the benefits and risks first.
Questions to ask your doctor
- What is my Gleason score, and what grade group is that?
- How many biopsy samples had cancer in them?
- What is my PSA, and what stage is the cancer?
- Is active surveillance an option for me?
- What are the side effects of each treatment option?
- Should I get a second opinion on my biopsy?
When to see a doctor
See a doctor right away if you have any of the urinary symptoms above, blood in your urine or semen, or pain in your back, hips or pelvis that won’t go away. If you’ve had a diagnosis, contact your care team about new symptoms or questions about your results.
Frequently asked questions
What is a normal Gleason score?
There’s no “normal” Gleason score, because it’s only given when cancer is found. In practice, scores run from 6 to 10. A score of 6, grade group 1, is the lowest and describes slow-growing, low-grade cancer.
Is a Gleason score of 6 cancer?
Yes. A Gleason score of 6 is grade group 1, which MedlinePlus describes as low grade. These cancers tend to grow slowly, and the NCI notes that some men may be offered active surveillance instead of treatment right away.
What does a Gleason score of 9 mean?
A Gleason score of 9 or 10 is grade group 5, the highest group. MedlinePlus describes it as high grade, meaning the cancer cells look very different from normal cells and are more likely to grow and spread. Your doctor will combine it with your stage and PSA to plan treatment.
Does a high Gleason score mean the cancer has spread?
Not by itself. The Gleason score describes how abnormal the cancer cells look, not where the cancer is. A higher score means the cancer is more likely to spread, but your stage, worked out from scans and other tests, describes whether it has.
How fast does prostate cancer grow?
It varies. MedlinePlus says lower Gleason scores mean slower-growing cancer, while higher scores mean faster-growing cancer that’s more likely to spread. The CDC notes that most prostate cancers don’t cause symptoms early on.
Should men get PSA screening?
The CDC shares the US Preventive Services Task Force advice: men aged 55 to 69 should decide for themselves after talking with their doctor about the benefits and risks. Men 70 and older shouldn’t be screened routinely.
The bottom line
The Gleason score tells you how abnormal prostate cancer cells look, from 6 (low grade) to 10 (high grade), and grade groups 1 to 5 sort those scores. It guides treatment together with your PSA, stage, health and wishes. Ask your doctor what your score and grade group mean for you.
Related reading
- Foods to avoid for prostate health
- Men’s mental health: signs and support
- Can vitamin B12 deficiency be a sign of cancer?