High-grade prostate cancer: Gleason score 8 to 10, Grade Groups and treatment

When a biopsy finds prostate cancer, a pathologist looks at the cells under a microscope and grades how abnormal they look. Cancer Research UK explains that the grade gives an idea of how aggressive the cancer is and how it might behave. Macmillan adds that grading describes how the cancer cells look and how likely they are to grow and spread outside the prostate.

High grade does not describe the size of the tumour or whether it has spread; that is stage. A high-grade tumour may be small and confined to the prostate, and a lower-grade tumour may be larger. This is why the grade is always considered with the stage and the PSA level.

The phrase high-grade prostate cancer is generally used for Gleason score 8 to 10, which corresponds to Grade Groups 4 and 5.

Macmillan explains that the Gleason score looks at the pattern of cancer cells in the prostate tissue and how different they are from normal prostate cells. There are patterns graded 1 to 5, and in practice biopsies are graded 3, 4 or 5. The doctor identifies the most common grade and the highest other grade seen and adds them, so that, for example, 3 + 4 = 7.

Cancer Research UK says the Gleason score has now been replaced by the Grade Group because doctors think it is a more accurate way to grade prostate cancer, but that people still ask about Gleason so it is shown alongside. The table below shows how they match and what each means, according to Cancer Research UK.

Macmillan says doctors look at the T stage, the Grade Group and the PSA level to identify a risk group. The Cambridge Prognostic Group system has five groups. NICE's guideline sets out the criteria: group 4 includes one of Gleason score 8 (Grade Group 4), PSA more than 20 microgram/litre or stage T3, and group 5 includes two or more of these, or Gleason score 9 to 10 (Grade Group 5), or stage T4.

Macmillan describes CPG4 as a higher risk of the cancer growing more quickly and spreading to another part of the body, and CPG5 as a high risk of the cancer growing quickly and spreading. In plain terms, a high-grade cancer places a person in the higher groups, and that shapes the conversation about treatment and about the tests needed to see whether it has spread.

The NHS says that if you are referred to a specialist because you might have prostate cancer you will have an MRI scan, and that a biopsy takes a small tissue sample through a needle to be checked for cancer cells. If cancer is diagnosed you may need more tests, including CT, MRI, PET or bone scans, to help the team decide on treatment.

NICE says not to routinely offer isotope bone scans to people with CPG 1 or 2 localised prostate cancer, which implies that scans for spread are more relevant in higher-risk groups. The team will explain which tests apply to you.

Cancer Research UK says that if the cancer has not spread, treatment may include surgery to remove the prostate (prostatectomy), external radiotherapy with or without hormone treatment, or internal radiotherapy (brachytherapy). Grade Group, PSA and stage, together with how much cancer there is in the biopsies, age and general health, possible gene changes and personal preferences, are used to recommend treatment. Cancer Research UK adds that some prostate cancers are slow growing and might never cause problems, in which case the doctor may suggest monitoring, which may be called active surveillance or watchful waiting.

The NHS lists hormone therapy as usable at all stages, noting that testosterone causes prostate cancer to grow and that hormone therapy with radiotherapy aims to cure early prostate cancer. NICE says to discuss the option of docetaxel chemotherapy with people with newly diagnosed non-metastatic prostate cancer who are starting long-term androgen deprivation therapy, have no significant comorbidities and have high-risk disease, as shown by T3 or T4 stage or Gleason score 8 to 10 or PSA greater than 40 microgram/litre, as a shared decision after explaining benefits and harms; treatment is started within 12 weeks of starting ADT.

The NHS notes that surgery carries risks, such as peeing without meaning to, problems having or keeping an erection and problems with orgasm, and that a prostatectomy means you will not be able to have children by having sex. NICE says that before radical treatment people and, if they wish, their partner should be told it will alter sexual experience, may cause loss of sexual function, may affect ejaculation and fertility (with sperm storage offered) and may affect urinary function.

These effects are part of why the specialist team and the clinical nurse specialist spend time on shared decision making, and why asking for a second opinion is reasonable.

The NHS says you will have regular check-ups during and after any treatment, and may have tests and scans. If the cancer has spread or cannot be cured, the aim becomes controlling the cancer and symptoms, and the NHS describes hormone therapy, chemotherapy and steroids as options, with a palliative care team supporting symptom control.

Macmillan explains that statistics are difficult to apply to individuals and that questions about outlook are best discussed with the cancer doctor or specialist nurse.

On the NHS, the pathway runs from GP and PSA testing to MRI and biopsy, a multidisciplinary team recommendation and treatment, with a clinical nurse specialist as the main contact. The NHS notes that Macmillan's free helpline is open every day from 8am to 8pm.

The grading and risk group framework above applies wherever you are treated, and a useful question to ask your team is which risk group you are in and how that influences the options. Anyone who wants a second opinion can ask their team how to arrange one.