Prostate cancer

Prostate cancer is now the most commonly diagnosed cancer of UK men.

The prostate is a small, walnut-sized gland situated near the bladder in men - it produces one component of semen.

There were 24,700 new cases of prostate cancer diagnosed in the UK in 1999 - it is one of the top ten most common in the country.

If found early, while still confined to the gland itself, chances of survival are excellent, and modern surgical techniques, combined with drugs such as Viagra, mean that life-saving operations don't have to mean the end of sex lives.

Professor Alan Horwich, is based at the Royal Marsden Hospital in London and the Institute of Cancer Research, where he carries out research funded by Cancer Research UK.

He said: "There are a broad range of prostate cancers, some of which are extremely gentle and indolent, which may not cause any significant ill health.

"Others have the ability to spread to other parts of the body and cause damage there."

He added: "If prostate cancer is caught at a time when it is confined to the prostate, generally it can be cured by radiotherapy and surgery."

Symptoms

The first sign of prostate cancer is usually problems passing water - usually an increased frequency or difficulty maintaining a full stream.

However, these symptoms are shared with benign prostate enlargement.

The symptoms are caused by the growth of cells, whether malignant or benign, pushing against the urethra, the thin tube which links the bladder to the penis.

Other symptoms to look out for are:

• Painful urination or ejaculation
• Blood in urine or semen
• Pain in lower back, hips or thighs

Of course, all of these symptoms could be caused by something else, for example infection - but should be investigated.

The doctor has several methods to check for the presence of prostate cancer.

The simplest of these is the digital rectal examination, in which a gloved finger is inserted into the rectum, through which an enlarged prostate can be felt.

Blood tests are the next step - prostate cancers cause the levels of certain chemicals in the blood to rise.

More sophisticated tests include the use of ultrasound scans, and x-rays.

Causes

The causes of prostate cancer are not yet understood.

However, there are certain things which place some men at higher risk of developing the disease than others.

These include other family members who have had prostate cancer.

There is some suggestion that a fat-rich diet may contribute to prostate cancer, but this is not proven.

Studies linking the cancer to vasectomy, an operation to remove a man's fertility, are contradictory.

Treatments

The key decision in prostate cancer is whether or not to treat at all.

In many older men, the cancer progresses so slowly that surgery and other treatments may cause more harm than good.

However, for those whose cancer is more aggressive, either already spreading or liable to spread beyond the prostate, surgery is usually the first option.

A prostatectomy means that the prostate gland is removed, normally along with small parts of the lymphatic system near the gland.

Unfortunately, the operation often causes nerve damage which can make it nigh-on impossible for men to achieve erection afterwards, or maintain complete control over urination.

However, modern "nerve-sparing" surgical techniques - combined with drugs such as Viagra - mean that the effects on both function and quality of life can be minimised.

As well as surgery, another option for doctors is radiotherapy which will be precisely targeted on the pelvic area.

And doctors are also tackling prostate cancer using the body's own hormones.

Prostate cells, including cancerous ones, are sensitive to levels of certain male hormones, and can be rendered far less active if levels are reduced.

However, one unwanted by-product of this is to lessen the natural sex drive of the patient.

The main advances in prostate cancer treatment are being made in surgery and radiotherapy.

Surgeons are learning how to remove the prostate without causing the problematic nerve damage which was inevitable in the past.

And radiotherapy technology advances mean that far higher doses can be targeted more precisely on the prostate, killing more cancer cells with fewer treatments.