Titles and Affiliations

Professor of Medicine
Associate Dean of Research Development
Vice-President of Genetic Medicine
Georgetown University Medical Center
Washington, D.C.

Research area

Developing strategies to improve treatment outcomes for HER2-positive breast cancer patients. 


Human epidermal growth factor receptor 2 (HER2) is a protein found on the surface of all breast cells. When generated at high levels, HER2 causes breast cells to grow rapidly—this occurs in approximately 20 percent of breast cancers which are called HER2-positive. These breast cancers tend to be more aggressive, however, they can also be effectively treated with HER2-targeted therapies. Dr. Swain has been focused on defining effective HER2-targeted therapies and led a clinical trial to test dual HER2-targeting with trastuzumab (Herceptin®) and pertuzumab (Perjeta®) plus docetaxel for treating metastatic HER2-positive breast cancer. This led to the approval of this combination for treatment of metastatic as well as early HER2-positive breast cancer—it is currently used as the standard of care throughout the world. Dr. Swain’s recent work focuses on immune cells in the HER2-positive breast tumor microenvironment and the role they play in how the tumor responds to treatment. This will help inform treatment decisions and potentially improve treatment outcomes for these patients.

Progress Thus Far

Studies have shown that one type of immune cell, called tumor infiltrating lymphocytes (TILs), can move from the blood into the tumor microenvironment where they can recognize and kill cancer cells. Specifically, the presence of TILs has been associated with better outcomes from HER2-targeted therapy. Based on these observations, Dr. Swain compared primary and metastatic HER2-positive breast cancers to determine if immune cells play a role in the progression to metastases. They found that primary samples had a higher infiltration of immune cells, CD3 and CD45. Further studies will help determine the role of immune cells in the progression to metastases and patient outcomes. 

What’s next

Dr. Swain and her colleagues will continue to evaluate TILS in the tumors of patients with early HER2-positive breast cancer that have been treated with HER2-targeted therapy and chemotherapy prior to surgery. In the coming year, they will also build on their observations and determine if TILs and other immune cells can be used as biomarkers to predict treatment outcomes and therefore provide clinicians with a potentially important decision-making tool.


Dr. Sandra M. Swain is an internationally-recognized breast cancer medical oncologist, and clinical translational researcher. She has authored nearly 300 articles in numerous peer-reviewed medical journals, such as the New England Journal of Medicine, Lancet Oncology, and the Journal of Clinical Oncology, on topics including inflammatory breast cancer, adjuvant treatment of breast cancer, the treatments of metastatic HER2-positive breast cancer, cardiotoxicity, and health care disparities.

Throughout her career, Swain has held many advisory and leadership positions with professional oncology societies and organizations across the globe. From 2012 through 2013, she served as President of the American Society of Clinical Oncology where she championed efforts to promote the advancement of women in medicine and that she continues today through her service on the board of Conquer Cancer, the ASCO foundation, and the Women Who Conquer Cancer initiative she established. Currently, she is a professor at the Georgetown University School of Medicine, the Associate Dean for Research Development at Georgetown University Medical Center, and the Vice President of MedStar Genetic Medicine–roles in which she works to improve patients’ access to cutting-edge treatments and technologies by expanding medical research opportunities across the MedStar Health system. She is also co-chair of the Early Breast Cancer Trialists’ Collaborative Group in Oxford and a visiting professor of clinical oncology at the University of Oxford, UK.

BCRF Investigator Since


Donor Recognition

The Friends and Family of Jen and Josh Feinberg Award

Areas of Focus