Genome mapping the key to cancer cure

Cancer cases will double by the year 2020 but the mapping of the human genome will give scientists new tools to fight the disease that by then will be striking 20 million people a year.

Imaging and biomarkers produced by cancer will speed diagnosis, surgery will disappear as a major treatment and instead of bombarding the body with toxic chemicals, new pills will be tailored to individual tumours to provide maximum impact and minimum discomfort.

"We are at the beginning of a revolution in cancer care," says Professor Karol Sikora, the former chief of the World Health Organisation's cancer programme.

Many of the advances will be due to genome research but improvements in imaging techniques, radiotherapy and vaccines will also play a big part.

"New screening technology coupled with drugs and vaccines that prevent cancer will come into routine use. Gene chips will be implanted under the skin and send radio signals to a home computer when abnormal fragments of DNA are detected, prompting further investigations," Professor Sikora said in a lecture at the Royal Society of British Scientists.

But the ability to detect cancer would also put more strain on healthcare systems and clinics because more people would need treatment.

Three-quarters of the 20 million cases a year predicted by 2020 will be in the developing world, already burdened with infectious diseases such as Aids, malaria and tuberculosis.

North America, Europe, Japan, Australia and New Zealand have the highest incidences of cancer but, ironically, as medical care and better sanitation and housing improve in the developing world, more people will live longer and will develop cancer.

Smoking, high-fat, low-fibre diets and viruses are three of the main causes of cancer. They account for 7.5 million cancer cases every year and will contribute to the increase of cancer in poorer countries.

The human papilloma virus is linked to cervical cancer, the hepatitis virus causes liver cancer, or hepatoma, and the Epstein-Barr virus is associated with lymphoma.

"The commonest cancer in West Africa is hepatoma and for $2 extra at the time of childhood vaccination, hepatitis immunisation has been shown to reduce the incidence of hepatoma by 90 per cent," said Professor Sikora.

"Yet politicians avoid tackling this issue as they see no gain until well beyond the end of their own careers."

New treatments will be simpler to administer because they will be tablets given over long periods and not injection or intravenous solutions.

"We are going through a technological explosion which will allow us to prolong survival way beyond the dreams of our ancestors. The aim of medicine must now be not only to add years to life, but life to years."

- REUTERS