The prostate gets bigger ('enlarges') gradually after the age of about 50. By the age of 70, about 8 in 10 men have an enlarged prostate. It is common for older men to have urinary symptoms caused by a benign (non-cancerous)
enlargement of the prostate (see separate page). Some men also develop prostate cancer.
What is cancer?
Cancer is a disease of the cells in the body. The body is made up from millions of tiny cells. There are many different types of cell in the body, and there are many different types of cancer which arise from different types of cell. What all types of cancer have in common is that the cancer cells are abnormal and multiply 'out of control'.
A malignant tumour is a 'lump' or 'growth' of tissue made up from cancer cells which continue to multiply. Malignant tumours invade into nearby tissues and organs which can cause damage.
Malignant tumours may also spread to other parts of the body. This happens if some cells break off from the first (primary) tumour and are carried in the bloodstream or lymph channels to other parts of the body. These small groups of cells may then multiply to form 'secondary' tumours (metastases) in one or more parts of the body. These secondary tumours may then grow, invade and damage nearby tissues, and spread again.
Some cancers are more serious than others, some are more easily treated than others (particularly if diagnosed at an early stage), some have a better outlook (prognosis) than others.
So, cancer is not just one condition. In each case it is important to know exactly what type of cancer has developed, how large it has become, and whether it has spread. This will enable you to get reliable information on treatment options and outlook. See separate page called
'What are Cancer and Tumours' for further details about cancer in general.
What is prostate cancer?
Prostate cancer is a malignant cancer which develops from cells in the prostate gland. It is one of the most common cancers. Most cases develop in men over the age of 65.
What causes prostate cancer?
A cancerous tumour starts from one abnormal cell. The exact reason why a cell becomes cancerous is unclear. It is thought that something damages or alters certain genes in the cell. This makes the cell abnormal and multiply 'out of control'. (See separate page called
'What Causes Cancer' for more details.)
Although the exact cause is unclear, certain 'risk factors' increase the chance that prostate cancer may develop. These include:
- Ageing. Most cases are diagnosed in older men.
- Family history and genetic factors. If your father or brother had prostate cancer at a relatively early age (before they were 60) then you have an increased risk. Prostate cancer is more common in black men than white men. Also, if the type of breast cancer which is linked to a faulty gene runs in your female relatives, then you are at increased risk. These factors point towards a 'faulty gene' which may occur in some men which increases their risk of developing prostate cancer.
- Diet is possibly a risk factor. As with other cancers, a diet high in fats and low in fruit and vegetables may increase the risk.
- Exposure to the metal cadmium may be a risk.
What are the symptoms of prostate cancer?
Prostate cancer is often slowly growing. There may be no symptoms at first, even for years. As the tumour grows, it may press on and 'irritate' the urethra, or cause a partial blockage to the flow of urine. Symptoms may then develop and can include one or more of the following.
- Poor stream. The flow of urine is weaker, and it takes longer to empty your bladder.
- Hesitancy. You may have to wait at the toilet for a while before urine starts to flow.
- Dribbling. A bit more urine may trickle out and stain your underpants soon after you finish at the toilet.
- Frequency. You may pass urine more often than normal.
- Urgency. You may have to get to the toilet quickly.
- Poor Emptying. You may have a feeling of not quite emptying your bladder.
Note: all the above symptoms are common in older men. Most men who develop the above symptoms do not have prostate cancer but have a benign (non-cancerous) enlargement of the prostate. However, it is best to get any new symptoms checked out by a doctor.
Other symptoms such as pain at the base of the penis or passing blood occasionally occur. (These do not occur with benign prostate enlargement.)
If the cancer spreads to other parts of the body, various other symptoms can develop. The most common site for the cancer to spread is to one or more bones, especially the pelvis, lower spine and hips. Affected bones can become painful and tender. Sometimes the first symptoms to develop are from secondary tumours in bones.
How is prostate cancer diagnosed?
Initial assessment
If a doctor suspects that you may have prostate cancer, he or she will usually:
- Examine the prostate gland. They do this by inserting a gloved finger through the anus into the rectum to feel the back of the prostate gland. A normal feeling prostate does not rule out prostate cancer. An enlarged feeling gland, particularly if it is not smooth to feel, may indicate prostate cancer.
- Do a blood test to measure the level of prostate specific antigen (PSA). PSA is a chemical which is made by both normal and cancerous prostate cells. Basically, the higher the level of PSA, the more likely that you have cancer of the prostate. However, a mild to moderately raised PSA can occur in other conditions. (If you have confirmed prostate cancer the PSA blood test is also used to monitor treatment. If treatment is working and cancer cells are killed then the level of PSA falls.)
Biopsy - to confirm the diagnosis
A biopsy is when a small sample of tissue is removed from a part of the body. The sample is then examined under the microscope to look for abnormal cells.
To confirm the diagnosis of prostate cancer a small biopsy of the prostate is taken by using a fine needle. This is usually done with the aid of a special ultrasound scanner. The probe of the scanner is about the size and shape of a finger. It is passed through the anus into the rectum to lie behind the prostate. This finds the exact position of the prostate. The doctor then pushes a fine needle into the back of the prostate from within the rectum to obtain the biopsy. Several samples are usually taken from different parts of the prostate.
To biopsy the prostate can be uncomfortable, so local anaesthetic is used to reduce the pain as much as possible.
Assessing the severity and spread of prostate cancer
The severity of the disease is mainly based on three factors - the grade of the cancer cells, the stage of the cancer, and the blood PSA level.
Grade of the cancer
The biopsy samples are looked at under the microscope to asses the cancer cells. By looking at certain features of the cells the cancer can be 'graded'. The common grading system used is called the Gleason Score.
- A Gleason score of 2, 3 or 4 is a low grade. The cells look reasonably similar to normal prostate cells. The cancer cells are said to be 'well differentiated'. The cancer cells tend grow and multiply quite slowly and are not so 'agressive'.
- A Gleason score of 5, 6 or 7 is an intermediate grade.
- A Gleason score of 8, 9 or 10 is a high grade. The cells look very abnormal and are said to be 'poorly differentiated'. The cancer cells tend to grow and multiply quite quickly and are more 'aggressive'.
Staging
If you are confirmed to have prostate cancer, further tests may be done to assess if it has spread. These tests are not advised in all cases. It depends on factors such as your age and the grade of the tumour cells. Tests which may be done include a bone scan, a CT scan, an MRI scan, an abdominal ultrasound scan, or other tests. (There are separate pages which describe each of these tests in more detail, eg.
CT Scan and
MRI Scan.) This assessment is called 'staging' of the cancer. The aim of staging is to find out:
- How much the tumour has grown, and whether it has grown through the wall of the prostate and into nearby structures such as the bladder wall.
- Whether the cancer has spread to local lymph nodes.
- Whether the cancer has spread to other areas of the body (metastasised).
The PSA level
As a general rule, the higher the PSA level in the blood, the greater the number of prostate cancer cells. The PSA level can give a good idea of how quickly the cancer is growing in the prostate or spreading to other parts of the body.
What are the treatment options prostate cancer?
Treatment options which may be considered include: watchful waiting (no active treatment), surgery, radiotherapy, hormone treatment, and less commonly, chemotherapy. Often a combination of two or more of these treatments are used. The treatments used depend on:
- The cancer itself - its size and stage (whether it has spread), the grade of the cancer cells, the PSA level, AND
- The man with the cancer - your age, your general health, and personal preferences for treatment.
For example, certain types of prostate cancer are confined to the prostate, are slow growing and are unlikely to affect your life expectancy. Some types are more aggressive, more likely to spread and may cause serious illness and lead to death unless treated. The risks and possible side-effects of treatment are another consideration.
You should have a full discussion with a specialist who knows your case. They will be able to give the pros and cons, likely success rate, possible side effects, and other details about the various possible treatment options for your type of cancer.
You should also discuss with your specialist the aims of treatment. For example:
- Treatment may aim to cure the cancer. In particular, the earlier the stage of the cancer, the better the chance of a cure. (Doctors tend to use the word 'remission' rather than the word 'cured'. Remission means there is no evidence of cancer following treatment. If you are 'in remission', you may be cured. However, in some cases a cancer returns months or years later. This is why doctors are sometimes reluctant to use the word cured.)
- Treatment may aim to control the cancer. If a cure is not realistic, with treatment it is often possible limit the growth or spread of the cancer so that it progresses less rapidly. This may keep you free of symptoms for some time.
- Treatment may aim to ease symptoms. Even if a cure is not possible, treatments may be used to reduce the size of a cancer which may ease symptoms such as pain. If a cancer is advanced then you may require treatments such as nutritional supplements, painkillers, or other techniques to help keep you free of pain or other symptoms.
Watchful waiting
In some cases it may be best not to have any active treatment but to see how the cancer develops. This is called 'watchful waiting'. Various factors are taken into account such as the stage of the cancer, your age, general health, the impact and potential side-effects if treatment were to be used, etc. Watchful waiting may be more appropriate for men where the cancer is not causing much in the way of symptoms, is slow growing, especially in older men. With a watchful waiting approach you will need regular check ups and the decision about treatment can be reviewed at any time.
Surgery
Removing the prostate can be curative if the cancer is in an early stage (confined to the prostate and not spread.) It is a major operation and so tends to be advised more often for younger men whose general health is good, especially if the cancer grade means the cancer is likely to spread in the future. Side-effects such as impotence may occur following surgery to remove the prostate.
Even if the cancer is advanced and a cure is not possible, surgery may still have a place to ease symptoms. For example, a blockage of the flow of urine may be eased by an operation.
Radiotherapy
Radiotherapy is a treatment which uses high energy beams of radiation which are focussed on cancerous tissue. This kills cancer cells, or stops cancer cells from multiplying. (There is a separate page which gives more details about
radiotherapy.)
Radiotherapy may be used as an alternative to surgery, or may be used in addition to surgery. Two types of radiotherapy are used for prostate cancer, external and internal. Again, the type chosen depends on various factors such as the size, grade, and stage of cancer, etc. Some people have both types.
- External radiotherapy. This is where radiation is targeted on the prostate cancer from a machine. (This is common type of radiotherapy used for many types of cancer.)
- Internal radiotherapy (brachytherapy). This treatment involves inserting a small radioactive implant into the cancerous tumour, or next to the tumour. Sometimes radioactive 'seeds' are placed into the prostate gland. The 'seeds' are left in place permanently but lose their radioactivity over time. Sometimes a larger radioactive implant is inserted into the prostate for a short time and then removed.
Even if the cancer is advanced and a cure is not possible, radiotherapy may still have a place to ease symptoms. For example, radiotherapy may be used to shrink secondary tumours which have spread to bones and are causing pain.
Hormone treatment
Prostate cancer cells need the male hormone called testosterone to grow and multiply well. Testosterone is made in the testes and circulates in the bloodstream. Hormone treatments aim to stop you from making testosterone or to block the effect of testosterone on prostate cancer cells. Hormone treatments dont cure prostate cancer but may greatly slow down the growth of the cancer for a number of years.
The level of testosterone can be reduced by surgery or by drugs.
- Surgery. This involves removing the testes (orchidectomy). Without testes you no longer make testosterone.
- Drugs. Two groups of drugs are available:
- Drugs which work on the pituitary gland. For example: goserelin, leuprorelin and triptorelin. (Your pituitary gland makes a hormone which circulates in the bloodstream to stimulate the testes to make testosterone. These drugs stop your pituitary from making this stimulating hormone.)
- Drugs which block the action of testosterone (anti-androgen drugs). For example: flutamide, bicalutamide and cyproterone acetate.
Hormone treatments can cause side-effects such as erectile dysfunction (impotence) and other problems. Hormone treatment may be used in addition to surgery or radiotherapy. It may be used alone in cases where the cancer is more advanced.
Chemotherapy
Chemotherapy is a treatment of cancer by using anti-cancer drugs which kill cancer cells, or stop them from multiplying. See separate page called
chemotherapy for more details. Chemotherapy is not used as much as the above treatments for prostate cancer.
What is the prognosis (outlook)?
The outlook for prostate cancer is very variable. Some prostate cancers are slow growing and do not affect life expectancy. On the other hand some are already spread to other parts of the body when they are diagnosed and can lead to death. The response to treatment is also variable. The specialist who knows your case can give more accurate information about your particular outlook, and how well your type and stage of cancer is likely to respond to treatment.
Screening for prostate cancer
Screening for prostate cancer is controversial. A routine blood test which shows a high PSA may indicate that you have prostate cancer. However, there are other causes of a high PSA. Also, many prostate cancers are slow growing and do not cause problems, particularly in older men. Some experts believe that if all men were screened then there may be many men found with a raised PSA level. Many men may then be investigated and treated unnecessarily with all the possible risks and side-effects of the investigations and treatment. Put simply, some people believe that screening for all men may do more harm than good.
Currently there is no national screening programme in the UK. However, you can decide for yourself if you would like a PSA test. It is best to discuss the pros and cons of the test with your GP. After counselling, if you decide that you would like the test, many GPs will do the test on request. There are other pages in this series which discuss the PSA screening test in more detail.
Further help and information
The Prostate Cancer Charity, 3 Angel Walk, Hammersmith, London, W6 9HX
Helpline: 0845 300 8383 Web:
www.prostate-cancer.org.ukProvides support and information for patients and their families.
CancerBACUP, 3 Bath Place, Rivington Street, London, EC2A 3JR
Tel: 0808 800 1234 Web:
www.cancerbacup.org.ukProvides information and support to anyone affected by cancer.
Cancer Research UK
Other support groups
©EMIS and PIP 2004
