You are here

Cynthia X. Ma, MD, PhD

Associate Professor, Medicine
Division of Oncology
Section of Medical Oncology
Washington University School of Medicine
St. Louis, Missouri

Current Research

Goal: To advance the use of precision medicine for patients with estrogen receptor (ER)-positive breast cancers.

Impact: Drs. Ma and Ellis are conducting a trial to test a predictive tool that identifies patients with ER-positive breast cancer who are at low risk of recurrence and may safely avoid chemotherapy following surgery. Their work could spare many from the toxicities of chemotherapy and lead to more personalized treatments.

What’s next: The team will continue to collect tumor and blood for molecular studies in patients enrolled in the trial.

Treatment with endocrine (anti-estrogen) therapy is successful in treating most breast cancers, but about 20 percent of women will experience a recurrence of their disease. Unfortunately, there is currently no way of predicting which patients will respond to endocrine therapy and which will not. Drs. Ma and Ellis are conducting a clinical trial to test a predictive index to identify patients who may be spared chemotherapy.

Full Research Summary

Research area: To identify biomarkers that can predict response to anti-estrogen (endocrine) therapies.

Impact: Estrogen receptor (ER)-positive breast cancer typically responds well to surgery and endocrine therapy. However, up to 20 percent of patients will experience a recurrence. It is therefore important to identify biomarkers that can identify those patients whose tumors are most likely to respond to endocrine therapy versus those that most likely will not. Drs. Ma and Ellis are analyzing a large number of patient blood and tumor samples to identify such biomarkers with the goal of developing better risk stratification and treatments.

Current investigation: The research team has completed patient accrual for the ALTERNATE trial. They will use data obtained from ALTERNATE to better understand how resistance to endocrine therapy occurs so better treatments can be developed, to identify patients at low risk of recurrence who do not need chemotherapy after surgery, and to develop a mutation-based classification of ER-positive breast cancer for targeted therapeutic intervention. In addition, they will continue to assess the utility of circulating tumor DNA in predicting late recurrence and endocrine therapy resistance.

What she’s learned so far: Dr. Ma’s analysis of the data from over 1000 patients has provided insight into a marker of the effectiveness of chemotherapy, called Ki67.

What’s next: The team will continue to analyze tumor samples obtained from patients enrolled in ALTERNATE trial, in particular, for Ki67 – a marker of cell proliferation – and estrogen receptor expression. Furthermore, they will continue to conduct molecular analysis on tissue biopsies and blood.


Dr. Cynthia Ma obtained her MD from Beijing Medical University in China and subsequently PhD in Developmental Biology from the University of Cincinnati. She completed her Internal Medicine residency from New Hanover Regional Medical Center at North Carolina followed by the Hematology/Medical Oncology fellowship at Mayo Clinic, Rochester, Minnesota. In 2005, she was recruited as a breast oncologist at Washington University School of Medicine (WUSM). She is currently an Associate Professor of Medicine and a research member of Siteman Cancer Center. In August 2014, Dr. Ma was appointed as the Clinical Director of the Breast Cancer Program at WUSM. Dr. Ma’s research includes preclinical and clinical trial development of molecularly targeted cancer therapeutics for the treatment of resistant breast cancer. She is the principal investigator for several biomarker directed clinical trials of biological agents including UCN-01, temsirolimus, MK2206, BKM120, IMC-A12, and palbociclib in breast cancer.

Large Researcher Headshot - Ma Cynthia

BCRF Investigator Since


Area(s) of Focus