Scientific breakthrough in determining early cancer risk

A ground-breaking study could pave the way for the introduction of a quick and simple £5 saliva test to determine a patient’s risk of developing breast or prostate cancer, and it could be available within just five years.

The saliva test would find those who are genetically susceptible to the cancers and lead to thousands of lives saved each year with high-risk patients being monitored and even undergo treatment early enough to stop a cancerous tumour from even beginning to develop.

The research into early cancer prevention was conducted by scientists at the University of Cambridge and the Institute of Cancer Research (ICR) in London and funded by Cancer Research UK (CRUK) and the Wellcome Trust.

Researchers studied the DNA extracted from approximately 200,000 people; of which half were suffering from cancer and half were healthy. The massive project spanned four years of thorough genetic analysis by 1,000 scientists and they described their findings as the ‘single biggest leap forward’ in relation to the genetic causes of prostate cancer.

Each person is born with three billion pieces of code comprised of chemical letters: A, C, T and G; known as the ‘genome’ and is passed to us from our parents. A single nucleotide polymorphism is a single letter variation in DNA between people and we can have millions of these variations. Because cancer patients were compared with healthy individuals, scientists were able to see the genetic spelling mistakes that were prominent in the cancer group.

They discovered more than 80 genetic markers which are linked to the risk of somebody developing cancers. There were 49 for breast cancer, 23 for prostate cancer and 11 for ovarian cancer. Unfortunately, scientists were unable to ascertain around 60% of the genetic risk factors for the cancer types they focused, however their findings can still help increase knowledge of the inherited causes of the condition.

Interestingly, for the prostate cancer patients, 18 of the 23 variants were attributed to the most aggressive forms of the disease.

The next step for scientists is to create simple blood or saliva tests that can accurately obtain the future risk breast and prostate cancers. These samples would probably have to be sent off for a lab analysis but the hope is to have results available immediately at the doctors’ surgery.

New medicine for difficult-to-treat cancers could also be produced in addition to a new ovarian cancer test. It is thought that even bowel and lung cancers risks may be found with similar methods.
Dr Harpal Kumar, chief executive of Cancer Research UK, said: “It can help us identify exactly what is driving different types of cancer, which could enable us to develop new therapeutic approaches.”
He added: “By understanding why some people seem to be at greater risk of developing cancer we can look towards an era where we can take steps to reduce their chances of getting cancer or pick up the disease at its earliest stages. The principle is broad and the potential gains are huge.”

Professor Ros Eeles, from the Institute of Cancer Research, also commented: “These results are the single biggest leap forward in finding the genetic causes of prostate cancer yet made. The work could have a big impact on the number of people dying from the disease, which is still far too high.”

One in two men will develop cancer by 2027

As the number of men developing cancer is on the rise, UK health experts believe that by the year 2027 men will have a one in two chance of developing the disease.

The increase will change from the current 44 in 100 chance, to a 50 in 100 chance and is mostly because of the fact that people are generally living longer according to Cancer Research UK who teamed with Wolfson Institute of Preventative Medicine at Queen Mary, University of London to offer forecasts for the future.

Projections were formulated after studying previous information available about cancer incidence and mortality rates, in addition to projected population data for the UK.

In 2010 it was calculated that 324,000 people were diagnosed with cancer in the UK and this is expected to hit 416,000 by 2027. For men, the total is expected to reach over 221,000, up from 164,000 back in 2010.

The projections estimated that more than 194,000 women will be diagnosed with cancer in 2027, compared with 160,000 in 2010. Therefore, the predictions seem to be a similar pattern for women compared to men, with a lifetime risk which will increase from 40 to 44 out of 100 according to the researchers.

Cancer Research UK’s chief executive Harpal Kumar says that ‘it’s only through research that we will be able to beat cancer’, further adding: “We need to do more work to understand what drives cancer and how we can prevent it, as well as developing new treatments to reduce the number of people who will die from it.”

As mentioned previously, age is predicted to be the biggest risk factor for the disease and it is thought that the biggest increases in new cases will be seen in cancers of the bowel and prostate, as well as melanoma – the most dangerous type of skin cancer and most often brought on because of ultraviolet light (radiation) from the sun or excessive sunbed use.

Dr Kumar says the figures offer an outlook into the future and what challenges health authorities may face. One such challenge is developing an efficient and effective method of screening men for prostate cancer.

Not every cancer within the prostate gland is aggressive or potentially life-threatening and some can live with this all their lives and experience no health problems. Unfortunately though, doctors do not have a reliable testing procedure in their possession that can identify ‘safe’ tumours that are ok to leave alone.

Alan White, chairman of the Men’s Health Forum and professor of men’s health at Leeds Metropolitan University, argues that another problem will be persuading men to attend screenings for prostate cancer should an effective test ever be developed. Prof White says that even though men have a higher chance of developing bowel cancer than women, a lot less men than women actually bother to go for screening for this cancer.

Prof White says: “It’s desperately important that men take up any opportunity to go for cancer screening that they can. Some men are fatalistic about cancer and screening. But screening does make a difference. If cancers are spotted earlier they are easier to treat. We also know that men who discuss screening with their doctor or their partner are more likely to take up the offer.”