Study confirms cancers- family link

Having cancer in the family can
increase your chances of developing
not only the same cancer but other
types too, research suggests.
A study of 23,000 people in Italy and
Switzerland found that for each of 13
cancers, close relatives had an increased
risk of the same disease.
But there was also evidence that a family
history of one cancer could significantly
raise the risk of others.
Cancer charities say risk depends on
genes, lifestyle and environment.
The research, published in the journal
Annals of Oncology, followed 12,000
patients with cancer at different sites in
the body.
They were compared with 11,000 people
without cancer.
The researchers collected information on
family history of cancer, particularly in a
first-degree relative (those who share
about 50% of their genes - namely a
parent, sibling or child).
They found people with a first-degree
relative with cancer of the larynx had
triple the normal risk of developing oral
and pharyngeal cancer.
Those closely related to someone with
oral and pharyngeal cancer had a fourfold
increased risk of oesophageal cancer,
while breast cancer doubled the risk of
ovarian cancer for female family
members.
Men had a 3.4-fold increased risk of
prostate cancer if a first-degree relative
had bladder cancer.
The research also confirmed some known
cancer risks. They include a raised risk of
women developing breast cancer if they
have a family history of bowel cancer.
Lifestyle factors
Study leader Dr Eva Negri, of the Mario
Negri Institute for Pharmacological
Research in Milan, Italy, told BBC News:
"If you have a relative with one type of
cancer your risk of the same type of
cancer is increased.
"What this study has highlighted is that
sometimes if you have a relative with
one cancer your risk of another cancer
can be increased.
"The relative risk of a different cancer
generally tends to be lower than for the
same cancer."
In some cases, the links between
different cancers may be due to shared
environmental factors, such as family
smoking and drinking habits, she said.
But there was also evidence of genetic
factors affecting multiple cancer sites in
the body.
Jessica Harris, Cancer Research UK's
senior health information manager, said
cancer risk is determined by a
combination of genes we inherit from our
parents, our lifestyles, and our
environment.
"Whether or not someone in your family
has had cancer, living a healthy life can
really help to stack the odds in our
favour, and reduce the risk of cancer,"
she said.
"The main things you can do are to be a
non-smoker, cut down on alcohol, and
stay in shape by being active and eating a
balanced diet."
Eluned Hughes, from the charity
Breakthrough Breast Cancer, said some
breast cancers do run in the family,
however it was vital that women
remembered most cases were not
hereditary.
"In order to fully understand the causes
of breast cancer, we need to study more
women over a longer period of time,"
she said.