There are over 200 different kinds of cancer. Cancer happens when a small bit of how a cell works or behaves goes wrong.

The human body is made up of hundreds of different sorts of cells which all have different jobs to do to make the body work. When cells go wrong, they grow the wrong way and they can start destroying healthy body tissue.

Scientists know a lot more about cancers now because so much research is going on to find out about it. But there's still lots to discover. Because there are so many different types of cancers that can happen anywhere in the body, there are different causes.

What experts do know is cancer is caused by damaged genes in your DNA. Genes are the set of coded instructions which decide what happens to a cell in its life. The instructions are kept in a cell's nucleus. But if genes get damaged, this can trigger wrong cell behaviour.

Cells start to behave out of control and they ignore the rules on how to behave. Experts reckon there are three main causes of gene damage: diet, smoking, harmful sun rays.

Two Doctor Gahutu John Bosco, a physiology professor at the National University of Rwanda medical school, says that knowledge about the biology of cancer has made some prevention measures possible.

These measures include health education to avoid exposure to risk factors, campaigns against smoking, a healthy diet and physical exercise. Other recommended measures are a low fat diet with plenty of fruits, vegetables, nuts and grains. High fibre diet particularly prevents cancer of the colon.

Gahutu adds that screening of patients before onset of signs and symptoms of the disease has made early and efficient treatment possible. This constitutes an important strategy of secondary prevention for cervical and colon cancer.

Cancer in Rwanda

In a 2006 study carried out in the anatomical pathology laboratory of Butare teaching hospital, 7216 samples were tested. Out of these, there were 1298 cancer cases representing 19.98 per cent of the samples.

The highest occurrence of cancer is among women who made up 53.6 per cent of those tested. Breast and cervical cancer pose a particular threat to the lives of women especially those aged above 42 years.

Today, Rwanda has medical equipment that can detect cancer in its early stages. However, the low turn up of patients for medical tests is still a problem.

The most diagnosed types of cancer in Rwanda include non-Hodgkin lymphoma, stomach, Kaposi sarcoma, skin cancer and cancer of the eye. Children under 15 years are mostly affected by non-Hodgkin lymphomas and eye cancer.

Cancer distribution in the country varies according to age. Non-Hodgkin lymphomas cancer is common among 1-34 years, though this goes hand in hand with the prevalence of HIV/Aids infections.

Lung cancer is now common in urban areas of developing countries. It is mainly caused by use of tobacco and inhalation of second-hand smoke.

Cancer rates may change downward with the awareness created by medical research findings. For example in most populations in the developed world, stomach cancer has been declining rapidly in recent decades, whereas colon, breast and prostate cancer are on the rise.

Preventive measures are straight clear; as countries become more industrialised and urbanised, environmental factors like pollution and unnecessary disposure of expired drugs and foodstuffs should be dealt with. The best individual preventive measure is checking on one’s eating habits.

The writer is a general medical practitioner.

E-mail: josephmunich06@yahoo.co.uk