Clear Search

Farrokh Dehdashti, MD

Washington University School of Medicine
Saint Louis, Missouri

Titles and Affiliations

Professor of Radiology, Division of Nuclear Medicine, Mallinckrodt Institute of Radiology,
Siteman Cancer Center

Research area

Testing a new imaging method to predict response to therapy in estrogen receptor positive/HER2-negative breast cancer.


Many individuals with hormone receptor (HR)-positive breast cancer can be treated successfully with endocrine therapy (ET), but the cancer can return. Some patients with recurrent disease will benefit from additional ET approaches, including addition of cell cycle inhibitors (CDK4/6i), but others who don’t respond will need to go on to chemotherapy. Currently, there is no good way to predict which choice is the best for an individual patient. Drs. Dehdashti and Linden are developing a method to use PET imaging, in order to determine—within days—whether an individual with recurrent HR-positive disease is likely to benefit from additional ET and CDK4/6i. This test could help to direct individuals quickly to the best treatment, sparing those likely to respond to ET from the side effects of chemotherapy, and avoiding the cost and delay from ineffective ET for those not likely to respond.

Progress Thus Far

The trial opened in the summer of 2023 and will open at 2 additional collaborating sites.

What’s next

The phase two trial will be performed in HR-positive/HER2-negative metastatic breast cancer patients. Before, during, and after treatment with ET and CDK4/6i (abemaciclib, Verzenio®) patients will receive a PET scan, using a special imaging tracer, which is designed to reveal if the estrogen receptor is still active in their tumors. Drs. Dehdashti, Linden and their teams will then assess if estrogen receptor activation correlated with patients’ response to this therapy.


Farrokh Dehdashti, MD, is Professor of Radiology at the Mallinckrodt Insitute of Radiology. An innovative translational researcher, Dr. Dehdashti focuses on applying PET imaging to the diagnosis and treatment of cancer. She is credited with conducting the first patient studies of several novel PET diagnostic compounds related to cervical, breast, and prostate cancers and has advanced the use of PET for detecting tumor hypoxia and tracking chemotherapy and radiation sensitivity and resistance.

Her early research on steroid hormones in breast cancer was the first to show that PET using F-18 fluroestradiol (FES), an estrogen analogue, can reliably and noninvasively assess tumor estrogen receptor status and can be used to predict response to endocrine therapy. That work was groundbreaking in its potential to save patients from having to undergo numerous invasive biopsies and being treated with ineffective endocrine therapy.

Dr. Dehdashti earned her medical degree from Pahlavi University School of Medicine in Iran in 1977 and competed her radiology residency in 1980 at the same institution. She served as chief resident and then research fellow in PET imaging in the division of nuclear medicine at Washington University School of Medicine before joining the faculty in 1990. In 2017, Dr. Dehdashti received the Daniel P. Schuster Award for Distinguished Work in Clinical and Translational Science at Washington University.

BCRF Investigator Since


Areas of Focus



Hannah Linden, MD

University of Washington School of Medicine
Seattle, Washington