One third of cancer deaths due to avoidable factors

By Patricia Reaney

LONDON (Reuters) – If people avoided major risk factors for
cancer, more than a third of the 7 million annual deaths from
the disease could be prevented, scientists said on Friday.

In a report in The Lancet medical journal, the researchers
estimated how many deaths from 12 types of cancer were caused
by exposure to nine risk factors.

They calculated that smoking, alcohol, obesity, poor diet,
unsafe sex, lack of exercise and other factors contributed to
2.43 million cancer deaths worldwide in 2001.

“A third of cancer deaths could have been avoided had those
risks been reduced,” said Dr Majid Ezzati of the Harvard School
of Public Health in the United States.

“Prevention is probably still our best bet for reducing
cancer deaths. It is by far larger than what we may be able to
achieve using medical technology.”

Smoking, which is linked to lung, mouth, stomach,
pancreatic and bladder cancers, is the biggest avoidable risk
factor, followed by alcohol and not eating enough fruits and
vegetables.

“Of the 2.43 million deaths, 37 percent of them are from
lung cancer,” said Ezzati. “The total lung cancer deaths in the
world are 1.23 million and of those 900,000 of them are caused
by these risk factors.”

Smoking has increased in developing countries in the past
few decades so the number of avoidable deaths could grow, he
added.

Obesity also plays a role in colorectal and breast cancer
in high income countries, according to the research.

Infection with the human papillomavirus (HPV) through
unsafe sex is a contributing cause of cervical cancer in women
in sub-Saharan Africa and parts of Asia, mainly because of a
lack of screening and clinical services.

Urban air pollution is a risk factor for cancer in eastern
and southern Asia, while indoor smoke from burning coal is a
particular problem in China.

Ezzati said hepatitis infection, which is linked to liver
cancer, is sometimes spread by the use of contaminated syringes
in health centers in poor countries.

More than 100 scientists around the world contributed data
for the study and reviewed medical evidence.