A study conducted by Canadian and U.S. researchers reveals that young women with abnormally high levels of an “insulin-like growth factor” called IGF-1 have seven times greater risk of breast cancer than do other women.
IGF-1 is produced by many of the body’s tissues and is important for normal growth. Unfortunately, it fosters the growth of cancer cells as well as normal, healthy cells, and also has been linked to prostate cancer. It is uncertain whether IGF-1 actually causes cancer; researchers only know that there is a connection between elevated IGF-1 levels and the disease. Study leader Dr. Susan Hankinson said the findings are hopeful and may lead to improved breast cancer screening, but that further study is needed.
Jeff Bristol of Bristol Royal Infirmary in Britain, believes that the study is especially significant because it departs from the past 50 years of study, which mainly focused on genetic damage. “This is powerful evidence that the incidence of cancer in not just due to genetics but also due to the hormonal balance in the body – and that those hormones could be your defense,” he said.
Breast Cancer Information Center