February 19, 2008 Edition 1

SCIENTISTS have made a breakthrough in their prostate cancer research, discovering seven new genetic variations linked to the development of the disease and which can raise a man’s risk of getting the cancer by up to threefold.

The scientists, funded by Cancer Research UK, have found the largest number of genetic risk factors to be uncovered by a single genome-wide study, representing a major advance in understanding the genetic basis of the disease. Six other genetic variations have also been linked with prostate cancer in two separate studies published simultaneously in the current issue of the journal, Nature Genetics.

This means we are closer to having a genetic test for the disease that could predict who is at risk. Those identified could then be targeted for regular screening and early treatment - in theory.

One test, called deCODE and marketed by an Icelandic company at £250 (R3 750), has already been launched. It checks for the presence of eight of the gene variations, but it has been dismissed by rival researchers as “premature”.

Cancer Research UK scientists say any genetic test raises difficult ethical and practical issues which must be addressed first, such as how men at high risk should be counselled and how often they should be tested for the presence of the disease. Their own test is not expected to be ready for three to four years.

Prostate cancer is the most common male cancer, with thousands of new cases and deaths a year. As a killer of men it is second only to lung cancer and not far short of breast cancer, which gets far more attention and at least 10 times more research funding.

Its incidence is rising rapidly, partly because doctors have begun to look for it and are finding cancer that, in the past, would have gone undiagnosed.

It runs in families - if you have a relative with the disease your own risk is doubled, and if he was diagnosed before 60, it raises your risk almost four- fold. There is an urgent need for an accurate test that can tell who is going to get prostate cancer and who will die from it without treatment.

The prostate is a gland, only present in men, surrounding the urethra, the tube that carries urine from the bladder to the penis. It is the size of a walnut and produces the semen in which the sperm, made in the testicles, can swim. In one in three men in middle age, the prostate becomes enlarged, causing symptoms such as difficulty in urinating, a weak stream or increased frequency. However, in nine out of 10 cases the cause of the symptoms is benign. Only in one out of 10 is it cancer.

The first thing a GP will do for a patient who complains of the above symptoms is check to see if the prostate is enlarged, which can be simply done by inserting a finger in the rectum and feeling it through the bowel wall. The next stage is a blood test for prostate specific antigen - the PSA test - which, if raised, may indicate the presence of cancer. That is followed by a biopsy, a procedure in which a hollow needle is inserted through the penis to take samples of tissue from the prostate to check for cancerous cells.

Prostate cancer is different from other cancers in one crucial respect - more men die with it than from it. It is curable, but may not need treatment. This is because in many men it is slow growing - so slow that they can live with it without ill effects and die of something else.

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