Type 2 drug could lower breast cancer risk

Metformin the drug commonly used to treat type 2 diabetes could help significantly reduce the risk of breast cancer.

Research, carried out by the University of Copenhagen, has suggested that women with diabetes using the drug were 40 per cent less likely to have dense breast tissue.

The study, which researchers say is the first to look at the impact of diabetes treatments on breast density, was unveiled at the European Breast Cancer Conference.

A total of 5,644 women aged around 56-years-old took part in the Danish Diet, Cancer and Health (DCH) study group.

Each participant had all attended mammographic screenings between 1993 and 2001.

The findings showed those used diet or medication to control their condition were far less likely to have dense breasts.

However, the women who regularly used insulin were twice as likely to have high breast density.

Although mammograms are the most successful way to detect breast cancer tumours early, high density breast tissue can sometimes prevent an accurate screening.

Dr Zorana Jovanovic Andersen, of the University of Southern Denmark, said: “Diabetes is associated with an increased risk of breast cancer, but the exact mechanisms which bring this about are still unclear.

“Diabetes is associated with an increased risk of breast cancer, but the exact mechanisms which bring but the exact mechanisms which bring this about are still unclear.”

Dr Andersen wants more research to be carried out so further investigation into the links between breast density and other risk factors for the disease can be looked at.

She said: “One of the characteristics of cancer cells is their ability to grow rapidly and uncontrollably, and to resist the programmed death that occurs in non-cancer cells. Therefore, growth factors are critical to cancer development and progression.

“We know that insulin is an important growth factor for all body tissues, and even if we do not know exactly how it affects the development of cancer cells, it is also highly plausible that it increases breast density.

“In the meantime, we would urge all women, both with diabetes and without, to take measures to reduce their risk of developing breast cancer through simple lifestyle changes, such as avoiding obesity, reducing alcohol consumption and exercising.”

Chair of the conference, Professor Fatima Cardoso, director of the breast unit of the Champalimaud Clinical Centre in Lisbon, Portugal, said: “There has been much research into the role of the insulin pathway in breast cancer, but the exact mechanisms are still unknown.

“This study shows clearly that a link between diabetes treatment and breast density, an important risk factor for the disease, has been made. I hope that these findings will lead to further research into the effect of cheap, easily-available drugs such as metformin, not just on breast density, but on breast cancer risk overall.”

Statistics currently suggest that one in eight women in the UK will develop breast cancer over their lifetime.

If detected early, the chances of recovery are normally good, The NHS advice women to check their breasts regularly for any changes such as dimples, lumps and puckering.