How much can you affect your risk to develop cancer? Elizabeth Tracey reports


Even people with some advanced cancers can benefit from genetic analysis of their tumors, a recent study found. William Nelson, director of the Kimmel Cancer Center at Johns Hopkins, describes the contribution of genetics to overall risk for developing cancer.

Nelson: There have been studies that look at inherited tendencies, environmental exposures, and just the error prone aspects of the way cells divide. There’s a significant inherited contribution to cancer that’s on the order of 30-40%. If you look at the environmental exposure logic, it’s 80% or more of all cancers are caused by environmental influences, and the propensity for one cell to divide into two and make some mistakes that ultimately would lead to cancers, that’s also at an estimate that comes in at roughly 40%.   :32

Nelson says the reason this adds up to more than 100% is because of the overlap between factors, and notes that risk can clearly be impacted by individual choices. At Johns Hopkins, I’m Elizabeth Tracey.