Unknown. It is very difficult if not impossible to attribute one factor alone as a cause of breast cancer. A recent study looked at stress levels in breast cancer patients and found the stress scores higher in those with more aggressive cancers, but it's hard to know whether the stress caused the aggressive form or if the aggressive cancer caused more stress. Regardless, stress, obviously, is never good.
Unclear. The data on this is unclear. Stress has a negative effect on many systems in the body.
Maybe. New research indicates that one form of hormone receptor negative breast cancer aka triple negative has found "stress" to be an independent risk factor for this type of breast cancer. This breast cancer is about 15% of all breast cancer. Little is known how to treat it and it has rather benign looking mammogram and ultrasound! dcis is not invasive--or really breast cancer--but can become ca.