Not reliably: in 1,706 women taking prevention drugs, chemical marks on DNA did little to predict who developed breast cancer. The women had a high risk of breast cancer. They were taking Selective Estrogen Receptor Modulators, drugs that block estrogen in some tissues and act like it in others. Researchers used blood samples collected when the women entered two earlier studies. They compared 587 women who developed breast cancer with 1,119 similar women who did not. The team studied chemical marks on DNA, which can affect how genes work. They compared marks at 887,318 spots. Some spots showed differences between the two groups. But the actual size of those differences was small. Next, researchers tested five ways to predict who developed cancer. Their middle prediction scores ranged from 0.524 to 0.590. On this scale, 0.5 means no better than chance, and 1 means perfect prediction. Adding scores based on inherited gene differences did not improve the results. A measurable difference is not always a useful prediction. These findings do not mean the prevention drugs failed. The source notes that these drugs lower breast cancer risk in high-risk women. What fell short was this method of predicting risk among women taking them. For BioSocial members tracking medication use and bloodwork, that distinction matters. A detailed test report may still offer little help estimating personal cancer risk. Comparing notes can focus on what each test measures, rather than treating every number as proof of protection. What has been your experience making sense of risk scores alongside your own bloodwork and medication records?