Cynthia Ma, MD, PhD

Medical Oncologist

Cynthia Ma

Appointment Options

Whether you’re seeking a new patient appointment or exploring treatment options and looking for a second opinion, our Siteman care coordinators are ready to assist you.

My Locations

Gary C. Werths Building at Siteman Cancer Center

Gary C. Werths Building at Siteman Cancer Center

On WashU Medicine Campus
4500 Forest Park Avenue, Saint Louis, MO 63108

Expertise & Training

Clinical Expertise

  • Breast cancer

Primary Academic Title

Professor of Medicine, Division of Oncology, Section of Breast Oncology, WashU Medicine

Board Certification

  • 2001: American Board of Internal Medicine, Internal Medicine
  • 2004: American Board of Internal Medicine, Hematology
  • 2005: American Board of Internal Medicine, Medical Oncology

Training

  • 1990 - 1991: Resident, Internal Medicine and Endocrinology, Beijing Medical University, Beijing, China
  • 1997 - 1998: Postdoctural Fellow, Endocrinology and Oncology, University of Cincinnati, Cincinnati, OH
  • 1998 - 2001: Intern and Resident, Internal Medicine, New Hanover Regional Medical Center, Wilmington, NC
  • 2001 - 2005: Fellow, Hematology and Oncology, Mayo Clinic, Rochester, MN

Education

  • 1990: MD, Beijing Medical University, Beijing, China
  • 1997: PhD, Developmental Biology, University of Cincinnati, Cincinnati, OH

Research & Selected Publications

Research Interest

Breast cancer, endocrine therapy, developmental therapeutics, biomarkers and pharmacogenetics

Research Publications

Unraveling TIME: CD8+ T cell- and CXCL11-driven endocrine resistance in breast cancer
Authors:

Kong T, Ma CX

Journal & Year:

J Clin Invest | 2026

Biomarkers of response to neoadjuvant palbociclib plus anastrozole in endocrine-resistant estrogen receptor-positive/HER2-negative breast cancer: a phase 2 trial
Authors:

Kong T, Mabry A, Highkin M, one or more additional authors omitted Ma CX

Journal & Year:

Nat Commun | 2026

Circulating Tumor Cell Dynamics after CDK4/6 Inhibitor for Hormone Receptor-Positive Metastatic Breast Cancer: A Biomarker Analysis from the PACE Phase II Study
Authors:

Gerratana L, Reduzzi C, Ren Y, one or more additional authors omitted Ma CX, one or more additional authors omitted Mayer EL

Journal & Year:

Clin Cancer Res | 2025

First-Line Camizestrant for Emerging ESR1-Mutated Advanced Breast Cancer
Authors:

Bidard FC, Mayer EL, Park YH, one or more additional authors omitted Ma C, one or more additional authors omitted Turner NC

Journal & Year:

N Engl J Med | 2025

A bedside-to-bench translational analysis of NF1 alterations and CDK4/6 inhibitor resistance in hormone receptor-positive metastatic breast cancer
Authors:

Lloyd MR, Chica-Parrado R, Weipert CM, one or more additional authors omitted Ma CX, one or more additional authors omitted Wander SA

Journal & Year:

EBioMedicine | 2025

Detection of Circulating Tumor DNA Using a Tissue-Free Epigenomic Assay Is a Highly Prognostic Biomarker in Early-Stage Triple-Negative Breast Cancer
Authors:

Ademuyiwa FO, Ma CX, Weilbaecher K, one or more additional authors omitted Davis A

Journal & Year:

Clin Cancer Res | 2025

Novel treatment approaches utilizing antibody-drug conjugates in breast cancer
Authors:

Davis AA, Hesse J, Pereira PMR, Ma CX

Journal & Year:

NPJ Breast Cancer | 2025

Stabilization of RUNX1 Induced by O-GlcNAcylation Promotes PDGF-BB-Mediated Resistance to CDK4/6 Inhibitors in Breast Cancer
Authors:

Zhou S, Zhang Y, Belmar J, one or more additional authors omitted Ma CX, one or more additional authors omitted Zhu W

Journal & Year:

Cancer Res | 2025