Jennifer Rosenbluth, MD, PhD

A recent study showed that short-term, low-dose therapy can provide lasting protection from cancer. Yet only two drugs are approved for breast cancer prevention in the US. One reason is the lack of clear signs that show a risk-reduction therapy is working. One possible sign is background enhancement on breast MRI. A higher level means a higher risk of getting breast cancer. When a patient lowers their risk by taking tamoxifen, the background also goes down. For others, it does not. This shows that the therapy is not working. We studied breast tissue to understand the reason for this background. We found that those with high levels had either high estrogen or signs of inflammation. In our new study, we will use tissue pieces from patients starting tamoxifen. Our goal is to find a molecular signal that shows the drug is working. For those who do not respond, we will test drugs that target inflammation. Finally, we will see if different background signals point to estrogen or inflammation. These signals could be assessed in a clinical trial at UCSF to support a personalized cancer prevention strategy.