The Gleason score and Grade Group both describe the microscopic growth patterns found in prostate cancer tissue. They are based on the same biopsy or surgical pathology findings but present the result in different ways.
The Gleason score shows the individual patterns used to calculate the grade, while the Grade Group converts the result into a category from 1 to 5. Your report may include both because they help your specialist assess the likely behaviour of the cancer alongside your PSA level, stage, imaging and other findings.
What Does Prostate Cancer Grading Mean?
Prostate cancer grading describes the microscopic growth patterns formed by the cancerous glands. More organised patterns that retain recognisable gland formation are generally associated with less aggressive behaviour, while higher-grade patterns show a greater loss of normal glandular structure.
Your grade is different from your cancer stage. Grade provides information about the cancer’s likely biological behaviour, while stage describes its location and whether it has extended beyond the prostate or spread elsewhere.
What Is the Gleason Score?
The Gleason score is the traditional system used to describe prostate cancer grade. A pathologist examines tissue collected during a biopsy or surgery and assigns Gleason patterns according to the microscopic arrangement of the cancerous glands. Patterns 3, 4 and 5 are normally used in contemporary reporting.
Two patterns are combined to calculate a score such as 3+3=6, 3+4=7 or 4+5=9. The resulting score helps estimate how the cancer may behave but must be interpreted alongside the Grade Group, PSA level, stage, imaging and other clinical findings.
What Is a Gleason Pattern?
A Gleason pattern describes the microscopic growth pattern and glandular architecture of prostate cancer. Modern prostate cancers are generally assigned patterns 3, 4 or 5, with higher numbers showing a greater loss of normal gland structure.
Pattern 3 forms separate recognisable glands, pattern 4 includes irregular, fused, poorly formed or cribriform glands, and pattern 5 shows little or no gland formation. These patterns are used to calculate the Gleason score.
Understanding Gleason Patterns
| Aspect | What It Means | Example | Why It Matters |
| Gleason pattern | Describes the microscopic growth and glandular architecture of prostate cancer | Assessed in biopsy or surgical tissue | Helps estimate likely cancer behaviour |
| Pattern 3 | Separate, recognisable cancerous glands remain present | More organised gland formation | Generally associated with less aggressive behaviour than patterns 4 or 5 |
| Pattern 4 | Includes poorly formed, fused or cribriform glands | Greater loss of normal gland structure | Associated with a higher risk of progression than pattern 3 |
| Pattern 5 | Shows little or no recognisable gland formation | Solid sheets, cords or individual cancer cells may be present | Represents the highest-grade Gleason pattern |
| Gleason score | Combines two clinically important patterns | 3+4=7 or 4+3=7 | Records the predominant pattern and an additional pattern |
| Biopsy assessment | A pathologist examines tissue samples under a microscope | Predominant pattern plus highest additional pattern | Determines the Gleason score and corresponding Grade Group |
How Is the Gleason Score Calculated?
On a prostate needle biopsy, the Gleason score is generally calculated by adding the predominant cancer pattern to the highest other grade identified. For example, predominantly pattern 3 cancer with an additional pattern 4 component is reported as Gleason 3+4=7.
The order matters because Gleason 3+4=7 contains predominantly pattern 3 and is Grade Group 2, while Gleason 4+3=7 contains predominantly pattern 4 and is Grade Group 3.
What Is a Grade Group?
The Grade Group system converts the Gleason score into one of five categories, ranging from Grade Group 1 to Grade Group 5. Grade Group 1 is the lowest category normally diagnosed, while Grade Group 5 contains the highest-grade microscopic patterns.
The system provides a clearer five-level scale, particularly because Gleason 3+3=6 is the lowest score normally assigned rather than a middle-grade result. Grade Group describes cancer grade and should not be treated as a complete assessment of prognosis or treatment needs.
Why Was the Grade Group System Introduced?
Grade Group is the contemporary five-tier system commonly used to communicate prostate cancer grade. It gives a clearer progression from Grade Group 1, the lowest grade, to Grade Group 5, the highest.
The Gleason score remains important because it shows the individual microscopic patterns behind the Grade Group. Pathology reports and clinical discussions may therefore include both results.
How Do the Two Systems Match?
The Gleason score and Grade Group system correspond to each other in a set way. If you have a Gleason score of 3+3=6, this is classified as Grade Group 1, while 3+4=7 is Grade Group 2 and 4+3=7 is Grade Group 3.
A Gleason score of 8 is classified as Grade Group 4, while Gleason scores of 9 or 10 are classified as Grade Group 5. This allows your specialist to use a simpler category alongside the detailed Gleason score when discussing your cancer.
Why Are 3+4 and 4+3 Different?
Although Gleason 3+4 and 4+3 both add up to a total score of 7, they are not the same. The difference is the amount of pattern 4 cancer present, with Gleason 3+4 containing mainly pattern 3 and a smaller amount of pattern 4.
If you have Gleason 3+4, your cancer is classified as Grade Group 2. Gleason 4+3 is classified as Grade Group 3 because it contains more pattern 4 cancer and is generally associated with a higher risk of progression.
What Does Grade Group 1 Mean?
Grade Group 1 corresponds to a Gleason score of 3+3=6. If you have Grade Group 1 prostate cancer, only pattern 3 cancer is found in the tissue examined, making it the lowest-grade category.
Some men with favourable, localised Grade Group 1 disease may be offered active surveillance. This allows your medical team to monitor the cancer closely and avoid or delay treatment when it is unlikely to provide additional benefit immediately.
What Does Grade Group 2 Mean?
Grade Group 2 corresponds to a Gleason score of 3+4=7. If you have this result, pattern 3 is the dominant cancer pattern, but a smaller amount of the more abnormal pattern 4 is also present.
Your treatment options depend on factors such as your PSA level, cancer stage, tumour volume and overall health. Depending on your individual risk, your specialist may discuss options including active surveillance, surgery or radiotherapy.
What Does Grade Group 3 Mean?
Grade Group 3 corresponds to a Gleason score of 4+3=7. If you have this result, pattern 4 makes up most of the cancer found in your tissue, making it less favourable than Grade Group 2.
Your treatment plan depends on your complete diagnosis, including your PSA level, cancer stage, scan results and overall health. Active treatment is more commonly recommended for Grade Group 3, but your specialist will discuss the most suitable approach with you.
What Does Grade Group 4 Mean?
Grade Group 4 includes prostate cancers with a Gleason score of 8. Possible Gleason pattern combinations include 4+4, 3+5 and 5+3, depending on the cancer patterns identified in your biopsy.
These are high-grade cancers with a greater risk of progression compared with lower Grade Groups. However, Grade Group 4 cancer may still be confined to the prostate and can sometimes be treated with curative intent when appropriate.
What Does Grade Group 5 Mean?
Grade Group 5 includes prostate cancers with Gleason scores of 9 or 10, such as 4+5, 5+4 and 5+5. These cancers contain Gleason pattern 5 and form the highest Grade Group category, with a greater risk of progression than lower Grade Groups.
Your Grade Group does not show whether the cancer has already spread. Staging scans, PSA level, TNM stage and other clinical findings are still needed to understand the extent of your cancer and guide treatment decisions.
Which System Is Used More Often Today?
Grade Groups are now commonly used when your specialist explains prostate cancer grade because the five-category system is easier to understand. It places your Gleason result into a simpler range from Grade Group 1 to Grade Group 5.
- Grade Groups: Provide a simpler five-level system that helps explain how aggressive your prostate cancer may be
- Gleason scores: Remain widely used in pathology reports and medical discussions because they provide detailed grading information
- Clinical communication: Specialists often use Grade Groups when explaining results because they are easier for many patients to understand
- Treatment planning: Both systems help doctors assess your cancer and consider the most suitable treatment approach
- Related information: Gleason scores and Grade Groups describe the same underlying tumour features but present the information differently
You may hear both terms during the same consultation because they provide related but slightly different ways of describing your cancer grade. Understanding both systems can help you feel more informed when discussing your diagnosis and treatment options.
Why Do Doctors Still Report the Gleason Score?
The Gleason score records the specific microscopic patterns used to determine your Grade Group. This is particularly useful when distinguishing Gleason 3+4=7 from 4+3=7, as both total seven but differ in which pattern is predominant and are assigned to different Grade Groups.
The Grade Group provides a simpler category, while the Gleason score preserves additional pathological detail. Your specialist may use both when explaining the likely behaviour of the cancer, but neither result should be interpreted without your PSA level, clinical stage, imaging and other relevant findings.
Can Different Biopsy Samples Have Different Grades?
Different biopsy samples may contain different Gleason patterns or Grade Groups because prostate cancer can vary between separate areas of the gland. The pathology report may list individual sample results and provide an overall or summary assessment.
The findings should not simply be averaged or reduced to the highest number without context. Your specialist will consider the grade, amount and location of cancer in each sample alongside the MRI, PSA level and clinical stage.
Can the Grade Change After Surgery?
The Gleason score or Grade Group reported after radical prostatectomy may differ from the biopsy result because the pathologist can examine the whole prostate rather than selected tissue samples.
The cancer may be upgraded if a higher-grade area is identified or downgraded if the complete findings are less concerning. This usually reflects more extensive tissue sampling rather than the cancer suddenly changing after surgery.
Do the Gleason Score and Grade Group Show the Stage?
No. Your Gleason score and Grade Group describe the microscopic growth patterns found in the cancer tissue, but they do not show whether the cancer has spread.
Your TNM stage, PSA level and scan findings provide separate information about the location and extent of your cancer. Your specialist combines all of these results to understand your overall risk and recommend the most appropriate treatment plan for you.
How Do They Affect Treatment Decisions?
For localised or locally advanced prostate cancer, your Grade Group or Gleason score is combined with your PSA level and clinical T stage to determine your Cambridge Prognostic Group.
The CPG helps guide discussions about monitoring, surgery, radiotherapy and other treatments. Cancer volume, imaging findings, general health and personal priorities are also considered, but they are not separate components of the formal CPG calculation.
Myth vs Fact
| Myth | Fact |
| The Gleason score and Grade Group are unrelated. | Grade Group is derived directly from the Gleason score. |
| Gleason 6 is a middle-grade result. | Gleason 3+3=6 is the lowest score normally assigned to prostate cancer. |
| Gleason 3+4 and 4+3 mean the same thing. | They total seven, but 4+3 contains predominantly pattern 4 and belongs to a higher Grade Group. |
| A higher Grade Group proves that the cancer has spread. | Grade describes microscopic growth patterns and likely behaviour, while staging assessments describe the cancer’s location and extent. |
| MRI can determine the Grade Group. | MRI can identify suspicious areas, but tissue examination is required for grading. |
| The biopsy grade can never change. | The grade may be revised when the whole prostate is examined after surgery. |
| Grade Group alone determines treatment. | PSA, clinical stage, imaging, health and personal priorities are also considered. |
Key Takeaways
- The Gleason score and Grade Group describe the same microscopic cancer findings in different ways.
- The Gleason score shows the individual growth patterns identified by the pathologist.
- Grade Group converts the result into a simpler category from 1 to 5.
- Gleason 3+3=6 is Grade Group 1, the lowest current prostate cancer grade.
- Gleason 3+4=7 and 4+3=7 belong to different Grade Groups because the predominant pattern differs.
- A higher Grade Group generally indicates a greater likelihood of aggressive behaviour.
- Grade does not show whether the cancer has spread.
- PSA level and clinical T stage are combined with grade to calculate the Cambridge Prognostic Group.
Frequently Asked Questions
- What Is the Difference Between a Gleason Score and a Grade Group?
The Gleason score records the microscopic growth patterns identified in prostate tissue, while the Grade Group converts the result into a category from 1 to 5. Both describe cancer grade rather than its location or stage. - Is the Gleason Score the Same as the Grade Group?
No. Your Gleason score and Grade Group are related but not identical. The Grade Group system converts your Gleason score into a clearer five-level category that is easier to understand when discussing your diagnosis and treatment options. - Why Are Grade Groups Used Instead of Only Gleason Scores?
Grade Groups provide a clearer five-level scale, particularly because Gleason 3+3=6 is the lowest score normally assigned rather than a middle-grade result. The Gleason score remains useful because it shows the individual patterns behind the Grade Group. - What Does a Gleason Score of 6 Mean?
Gleason 3+3=6 corresponds to Grade Group 1 and is the lowest current prostate cancer grade. Its overall risk still depends on the PSA level, clinical stage, cancer extent and other findings. - Why Are Gleason 3+4 and 4+3 Different?
Although both scores add up to 7, they are not the same. Gleason 3+4 contains mainly pattern 3 cancer with a smaller amount of pattern 4, while Gleason 4+3 contains more pattern 4 cancer and is generally considered more aggressive. - What Does Grade Group 1 Mean?
Grade Group 1 corresponds to Gleason 3+3=6. It represents the lowest-grade category, and some men with favourable, localised disease may be offered active surveillance rather than immediate treatment. - What Does Grade Group 5 Mean?
Grade Group 5 includes Gleason scores of 9 or 10, such as 4+5, 5+4 and 5+5. It is the highest Grade Group category and contains the highest-grade microscopic growth patterns. - Does a Higher Grade Group Mean the Cancer Has Spread?
No. Your Grade Group describes the cancer’s microscopic growth patterns and does not show whether the cancer has spread. Your TNM stage, PSA level and scan results are needed to understand the extent of your cancer. - Can My Grade Group Change After Surgery?
The Grade Group may differ after radical prostatectomy because the pathologist can examine the entire prostate. A higher- or lower-grade result usually reflects more complete sampling rather than a sudden biological change. - How Do Gleason Score and Grade Group Affect Treatment Decisions?
For non-metastatic cancer, Grade Group or Gleason score is combined with PSA and clinical T stage to calculate the Cambridge Prognostic Group. Imaging, cancer extent, general health and personal priorities are then considered when treatment is discussed.
Final Thoughts: Gleason Score and Grade Group
The Gleason score and Grade Group describe the same prostate cancer grading findings in different ways. The Gleason score records the microscopic patterns identified by the pathologist, while the Grade Group converts the result into a category from 1 to 5 that may be easier to understand.
If you are considering prostate cancer surgery in London, feel free to contact us to arrange a consultation and receive personalised advice on your diagnosis, treatment options, and recovery.
References
- Berney, D.M., Beltran, L., Fisher, G., North, B.V., Greenberg, D., Møller, H., Soosay, G., Scardino, P. and Cuzick, J. (2016) ‘Validation of a contemporary prostate cancer grading system using prostate cancer death as outcome’, British Journal of Cancer, 114(10), pp. 1078–1083. Available at: https://pubmed.ncbi.nlm.nih.gov/27100731/
- Cancer Research UK (2025) Cambridge prognostic groups and risk groups for prostate cancer. Last reviewed 22 May 2025. Available at: https://www.cancerresearchuk.org/about-cancer/prostate-cancer/stages/cambridge-prognostic-group-cpg
- Cancer Research UK (2025) Grade Groups for prostate cancer. Last reviewed 21 May 2025. Available at: https://www.cancerresearchuk.org/about-cancer/prostate-cancer/stages/grades
- Epstein, J.I., Amin, M.B., Reuter, V.E. and Humphrey, P.A. (2017) ‘Contemporary Gleason grading of prostatic carcinoma: an update with discussion on practical issues to implement the 2014 International Society of Urological Pathology consensus conference on Gleason grading of prostatic carcinoma’, The American Journal of Surgical Pathology, 41(4), pp. e1–e7. Available at: https://pubmed.ncbi.nlm.nih.gov/28177964/
- Epstein, J.I., Egevad, L., Amin, M.B., Delahunt, B., Srigley, J.R. and Humphrey, P.A. (2016) ‘The 2014 International Society of Urological Pathology consensus conference on Gleason grading of prostatic carcinoma: definition of grading patterns and proposal for a new grading system’, The American Journal of Surgical Pathology, 40(2), pp. 244–252. Available at: https://pubmed.ncbi.nlm.nih.gov/26492179/
- Epstein, J.I., Zelefsky, M.J., Sjoberg, D.D., Nelson, J.B., Egevad, L., Magi-Galluzzi, C. et al. (2016) ‘A contemporary prostate cancer grading system: a validated alternative to the Gleason score’, European Urology, 69(3), pp. 428–435. Available at: https://pubmed.ncbi.nlm.nih.gov/26166626/
- Goel, S., Shoag, J.E., Gross, M.D., Al Hussein Al Awamlh, B., Robinson, B., Khani, F. et al. (2020) ‘Concordance between biopsy and radical prostatectomy pathology in the era of targeted biopsy: a systematic review and meta-analysis’, European Urology Oncology, 3(1), pp. 10–20. Available at: https://pubmed.ncbi.nlm.nih.gov/31492650/
- National Institute for Health and Care Excellence (2019) Prostate cancer: diagnosis and management. NICE guideline NG131. Last updated 15 December 2021 and last reviewed 13 August 2025. Available at: https://www.nice.org.uk/guidance/ng131
- Prostate Cancer UK (2023) What do my test results mean? Updated August 2023. Available at: https://prostatecanceruk.org/prostate-information-and-support/just-diagnosed/what-do-my-test-results-mean