Overweight, insulin resistant women at greater risk of breast cancer diagnosis
Women who have risk factors commonly associated with Type 2 diabetes also have much greater odds of being diagnosed with an advanced breast cancer, according to research presented to the Population Health Conference 2008 in Brisbane, by University of Melbourne researcher, Dr Anne Cust.
Dr Cust was a key collaborator on the international study, which found that women who were overweight or had signs of insulin resistance, such as elevated blood glucose or insulin levels, were about 50% more likely to be diagnosed with an advanced breast cancer tumor.
Researchers tracked more than 60,000 Swedish women over a 20 year period, from 1985 to 2005.
All were cancer free when recruited, and their blood tested for glucose, insulin and other hormones associated with obesity and diabetes risk.
Insulin resistance is most commonly caused by being overweight and inactive and is often a precursor to Type 2 diabetes.
Dr Cust said that previous research had shown a strong link between being overweight, and increased breast cancer risk in post menopausal women, but this study was the first to demonstrate the influence of insulin resistance on the stage of cancer diagnosis.
“Women with insulin resistance or who were overweight ,were less likely to be diagnosed with stage 1 breast cancers, but at greater risk of being diagnosed with stage 2 to 4 tumors; larger, more advanced cancers,” she said.
“We know that being overweight and having insulin resistance is a risk factor for getting cancer but, in the case of breast cancer, our study indicates that the cancer will be more advanced.”
Dr Cust’s research was conducted with colleagues from Umea University, Sweden, and the German Cancer Research Centre.
It was recently published in the journal Breast Cancer Research and Treatment.
