TONY EASTLEY: An international study has established a link between Type-2 Diabetes and advanced breast cancer.
It's been known for a while that being overweight puts post-menopausal women at greater risk of breast cancer, but now it's been found that women who are resistant to insulin, or who are overweight, are 50 percent more likely to be diagnosed with the cancer and only when it's in its advanced stages.
The finding comes after an international research team followed more than 60,000 Swedish women over 20 years.
Dr Anne Cust from the University of Melbourne is a collaborator in the study and she is preparing to present the findings at a medical conference in Brisbane today.
Dr Cust is speaking here with AM's Simon Lauder.
ANNE CUST: We found that women who were overweight or who have signs of insulin resistance which is a precursor to Type-2 Diabetes were more likely to be diagnosed with an advanced breast cancer.
SIMON LAUDER: So if a woman is overweight or has early signs of Type-2 Diabetes, how much more likely is she to get advanced stage breast cancer?
ANNE CUST: About 50 percent more likely so they are less likely to get an early stage tumour but more likely to get a more advanced stage breast tumour.
SIMON LAUDER: For overweight or diabetic women, it doesn't necessarily mean they are more likely to get breast cancer but they are less likely to be diagnosed early?
ANNE CUST: Yes, our study was looking particularly about the stage of breast cancer, the diagnosis and we found that they were, women who were overweight or with insulin resistance were more likely to get it, be diagnosed with an advanced stage of breast cancer.
We don't know the exact reasons why that might be. It might be that the cancer is growing more quickly or that it wasn't diagnosed early but we need to do more research to find out exactly why that might be.
SIMON LAUDER: Is there a hypothesis as to why overweight or diabetic women aren't diagnosed earlier with breast cancer?
ANNE CUST: It may be that the hormones that are involved, that are linked with being overweight or having insulin resistance, might be making the tumour grow more quickly but we need to do more research to find out exactly why that might be the case.
SIMON LAUDER: Does it mean that women who are at risk of Type-2 Diabetes should be screened for breast cancer more often?
ANNE CUST: Not necessarily I think. The question of screening is something that would need to be looked at separately but I think it is just providing another indication that being overweight is linked to lots of different health problems and this is another reason to get off the couch and try to stay active and maintain a healthy weight.
And also, the link with insulin resistance may provide a new avenue of research for looking at the causes of breast cancer and possibly new treatments.
TONY EASTLEY: Dr Anne Cust from the University of Melbourne. Simon Lauder the reporter.
Copyright 2006 Australian Broadcasting Corporation. All rights reserved.
