Understanding prostate cancer
What is the prostate gland?
The prostate is a small gland found only in men and contributes to the production of healthy sperm. It is about the size and shape of a walnut, however it tends to get bigger with increasing age. It lies just below the bladder and surrounds the urethra, the tube that carries urine out of the body. Prostate problems are common, particularly in men aged over 50 and can affect how men urinate and their sexual function.
Cancer of the prostate occurs when some cells in the prostate start to grow out of control. Each year in the UK, approximately 47,000 men are diagnosed with prostate cancer, with some 11,000 dying from the disease. Prostate cancer is rare in men under 50 years of age, with the most common age of diagnosis being between 65 and 69.
Men are at higher risk if they:
- have a family history of prostate cancer – if one first-degree relative has prostate cancer, the risk is at least doubled.
- are of black ethnic origin, with their lifetime risk being 1 in 4 compared to 1 in 8 for white Caucasian men.
- are overweight or obese, although this is specifically for advanced prostate cancers.
Most early prostate cancers do not cause any symptoms. If there are symptoms, many are the same as those caused by an enlarged non-cancerous prostate. Symptoms can include problems urinating, issues with erections and ejaculation, pain or stiffness in the lower body, extreme tiredness and loss of weight and appetite.
The prostate specific antigen (PSA) blood test may help to find out if men are more likely to have prostate cancer. Whilst the PSA level is expected to increase with age, a raised PSA level could indicate the presence of prostate cancer and may warrant further investigation. A rise in PSA over time can also be significant, even if the level remains within the normal range. It is for these reasons that regular monitoring is advised.
It is not a perfect test however, as approximately 3 in 4 men with a raised PSA level will not have cancer and the test can also miss about 15% of prostate cancers. A raised PSA may also occur in other non-cancerous conditions, such as enlargement of the prostate or a urinary tract infection.
Here at The London General Practice, we offer a sophisticated test that includes a free/total PSA ratio, which can help to increase the accuracy of diagnosis by determining the need for further investigations.
Before a PSA test, men should not have:
- an active urinary infection
- exercised vigorously or ejaculated in the previous 48 hours
If a raised PSA level is identified, patients will require an examination of the prostate and possibly further imaging in the form of an MRI. Depending on the outcome of this initial assessment, a prostate biopsy may be offered, which involves taking small samples of the prostate through the back passage and checking them for cancer. The most common complications of having a biopsy are bleeding and infections, with most men also experiencing blood in urine and sperm after biopsy. In up to one in five men who have a prostate biopsy, prostate cancer will be missed, in which case follow-up and additional biopsies may be needed.
Treatment for prostate cancer will depend on the patient’s individual circumstances, including the stage of disease, the man’s age and general health and there are important quality of life differences between each option.
Watchful waiting and active surveillance
For many men with prostate cancer, no treatment will be necessary and instead watchful waiting is often recommended, particularly for older men when it is unlikely the cancer will affect their life expectancy. This involves observing for the development of symptoms of cancer and may also be recommended if a patient’s general health is not be amenable to any form of treatment.
Some men with slow-growing cancers may be offered active surveillance, which involves regular PSA tests and MRI scans to monitor the cancer. This aims to avoid unnecessary invasive treatments of harmless cancers, with treatment offered only if the cancer starts to progress.
Radical prostatectomy is the surgical removal of the prostate gland and can be done as an open, keyhole or robotically-assisted procedure. This treatment is an option for potentially curing localised prostate cancer. However, recent evidence demonstrates possible long-term side effects including infertility, erectile dysfunction and urinary incontinence. In addition, up to 20% of men will have residual tumour.
External beam radiotherapy and brachytherapy
Radiotherapy involves using radiation to kill cancerous cells and is an option for curing localised prostate cancer or slowing the progression of advanced prostate cancer, thereby relieving symptoms. Radiotherapy is an alternative to surgery, with evidence suggesting that external irradiation offers the same long-term survival results and quality of life outcomes as surgery. Long-term side effects can include erectile dysfunction and a higher risk of diarrhoea and discomfort compared with other treatments.
Brachytherapy is a form of radiotherapy where the radiation dose is delivered inside the prostate gland using a number of tiny radioactive seeds surgically implanted into the tumour. The idea behind this method is to deliver radiation to the prostate while minimising damage to other tissues. Whilst the risk of bowel problems is slightly lower, the risk of urinary problems is higher than with radiotherapy.
Hormone therapy is often used in combination with radiotherapy to increase the chance of successful treatment or used after radiotherapy to reduce the risk of cancerous cells returning. Hormone therapy alone can be used to slow the progression of advanced prostate cancer in order to relieve symptoms.
High-intensity focused ultrasound (HIFU) is sometimes used to treat localised prostate cancer. This involves inserting an ultrasound probe into the rectum that releases high-frequency sound waves through the wall of the rectum and into the prostate, destroying cancerous cells by heating them to a high temperature.
Cryotherapy is another method of killing cancer cells by freezing them and sometimes used to treat men with localised prostate cancer.
Both HIFU and cryotherapy treatments are still going through clinical trials for prostate cancer and their long-term effectiveness has not yet been conclusively proven.