Clinical trial looks to improve treatment of early-stage breast cancer

Dr. Amy Fowler, a radiologist and active researcher with Carbone Cancer Center, is studying how a targeted imaging agent, tracked by positron emission tomography (PET) and magnetic resonance imaging (MRI) scans, can be used to observe the effectiveness of hormone therapy given before surgery.

“The overall focus of this study is to better identify the cancers that are truly hormone sensitive versus those that may be hormone therapy resistant, and that helps in selecting a different treatment,” she said.

Hormone therapy, also called endocrine therapy, is intended to deprive cancer cells of hormones like estrogen and progesterone that can fuel cancer growth. Given before surgery, also called a neoadjuvant treatment, it helps shrink tumors and improve surgical outcomes. While most types of breast cancer are receptive to this therapy, patients with a hormone-resistant type of breast cancer see no benefit.

Fowler’s study hopes to prove that use of their imaging agent, designed to bind to progesterone receptors in breast cancer cells, can accurately distinguish between cancers that are receptive to hormones and those that are not. Using PET/MRI, her team is tracking the uptake of this imaging agent by the cancer cells while the patient undergoes two weeks of endocrine therapy before surgery.

“The idea is that, if the breast cancer is endocrine sensitive, we should see that tracer signal go down, and if we don’t see any change, that might suggest that they’re less sensitive to endocrine therapy, and other options, such as chemotherapy or other targeted therapies, would potentially be more effective for those patients,” she said.

Fowler hopes this imaging technique can eventually become standard for clinical use as a less-invasive alternative to using needle biopsies to track treatment progress.

“In my clinical work at the Breast Center as a radiologist, we do image-guided breast biopsies, and many patients say that it would be nice to get all the information about a tumor, or as much as you can about a tumor, without needing more biopsies,” she said.

This clinical trial builds on years of lab research and pilot studies by Fowler and colleagues at UW to test the imaging agent. Fowler also collaborates with members of the Breast Cancer Research Advisory Network at UW, a group comprised of breast cancer survivors, caregivers and advocates who work with researchers to provide a patient perspective on research proposals, grant submission and designing clinical trials.

“It’s been very key for, especially for clinical trials, to understand what’s reasonable to ask of patients in terms of the study design,” she said of their perspectives.

This trial is currently open for patients who are interested in participating. For more information about this and other trials, contact the Clinical Trials Nurse Navigator team at (608) 262-0439 or clinicaltrials@cancer.wisc.edu, or visit uwhealth.org/cancertrials.