Separating fact from fiction

The number of new cases of cancer diagnosed each year in Europe rose by 300,000 in 2004-2006, according to new estimates published last week. There are also several myths surrounding the disease. Michelle McDonaghseparates the facts from the fiction.

Cancer is on the increase and infecting more young people than ever before. People living near mobile phone masts and landfill sites are at greatest risk of the disease and, despite 50 years of research, the outlook for cancer patients is no better than it was in the 1960s.

All of the above statements are complete myths, although most people outside the medical profession will be surprised to hear this. There is so much conflicting information surrounding the Big C - which one in three of us will develop in our lifetime - that people don't know what to believe.

The director of the Irish National Cancer Registry, Dr Harry Comber, is one man who can separate the facts around cancer from the fables. He points out that the cause of cancer is damage to DNA that takes place over a long period and a number of different factors are involved, so it is not possible to say that there is a cause for cancer in the same way as a virus causes influenza or a bacterium causes TB.

As a result, when studying cancer, scientists must look to populations to examine whether there is a link between exposure to different things and getting cancer.

"One of the persistent beliefs about cancer is that diet is very important, but although a lot of work has gone into looking at the components of foods to see what might cause cancer, there are no certain answers," he says.

"It's quite obvious that people who eat diets rich in fruit and vegetables have a lower incidence of cancer but we are not certain if this is because they are eating fruit and veg or not eating other things," says Comber.

Being overweight is a major cancer risk factor and this risk increases considerably if you are obese. This, Comber points out, shows that it's not so much what you eat that's important, but how much you eat.

Although some cancers have already been

cured to a certain extent, such as testicular cancer and leukaemia in children, Comber does not think there is such a thing as a generic cure for cancer as the disease has so many different forms.

"I think we will see incremental

improvements in surgery and radiotherapy.

For the majority of patients, surgery is curative but there's no magic bullet for cancer. There are a lot of targeted treatments for specific cancers but nothing for the major cancers.

"I think it's a matter of holding cancers in check with treatment until the person dies of something else. Cancer will become a chronic rather than a terminal disease, a bit like HIV," he says.

The way forward, in Comber's opinion, is through more detailed knowledge about the risk factors associated with cancer, more effective intervention for the risk factors already understood such as smoking, diet and exercise, and more investment in treatment facilities.

"While there has been a lot of promising work done in areas like immunotherapy and stem cell research, nobody has yet found a cure for cancer," he says.

"However, I think there are lots of small things we can do to make a patient's life more tolerable and we shouldn't lose sight of the individual in the midst of the high tech. For example, a lot of work has been done on making patient waiting areas more pleasant, providing overnight beds for relatives and providing patient transport instead of ambulances.

"It's these kind of things that can make a huge difference to the patient and their family."

Cancer Myths:

Fable 1: Mobile phone masts and mobile phones cause cancer.

As the radiation from mobile phones and masts is not ionising radiation, it has no affect on DNA and there is no evidence that they cause cancer. The level of emission from a mobile phone mast is actually thousands of times lower than from a mobile phone and, ironically, the more masts there are, the less radiation your mobile phone emits as your signal will be stronger.

Fable 2: Cancer is on the increase, especially in young people.

It is clear from the National Cancer Registry data that the incidence of cancer in Ireland is not on the increase and the risk of dying from the disease has fallen in the past 10 years. While the number of cancer cases and deaths has risen due to an ageing population, the risk of getting cancer and dying is actually falling. Cancer is a very age-dependant disease and the risks of developing it double every eight years from the teens onwards. As you age, the people around you who are also ageing are twice as likely to die from cancer which gives rise to the misperception that there is a huge rise.

Fable 3: The war against cancer is not getting anywhere.

Cancer survival rates are increasing by about two per cent a year. While there have been no major breakthroughs in terms of a cure, there have been improvements in surgery, anaesthesia, medical support for patients, drug treatments and radiotherapy. There has also been an overall improvement in the general fitness of the population and life expectancy is increasing so people are better able to withstand treatment than they did 20 years ago.

Fable 4: Screening for cancer will solve all our problems.

There seems to be confusion between earlier detection of cancer and screening programmes. While it's very valuable for the individual cancers picked up, screening has a very small impact on the overall population. There is no doubt that cervical screening works but as this form of cancer accounts for only 70-80 deaths a year, it does not have a big impact.

Breast screening also works but it targets only a portion of the population and in those it reduces breast cancer by 25 per cent. Prostate screening probably does not work at all in terms of reducing mortality, says Comber.