Susan M. O'Brien, MD

Dr. Susan M. O’Brien UCI Health hematology oncologist who specializes in hematology and medical oncology.

As associate director for clinical research at the UCI Health Chao Family Comprehensive Cancer Center, she oversees and coordinates clinical cancer research across the entire UCI Health enterprise, including medical oncology, radiation oncology, surgical oncology and gynecologic oncology.

Her clinical expertise is in the diagnosis and treatment of acute and chronic lymphocytic leukemia and she is actively involved in clinical trials as director of the UCI Health Sue and Ralph Stern Center for Cancer Clinical Trials and Research.

O’Brien earned her medical degree at the University of Medicine and Dentistry of New Jersey in Newark, N.J., where she also completed her residency in internal medicine, followed by a fellowship in Hematology/Oncology at University of Texas MD Anderson Cancer Center in Houston, Tex.

An internationally recognized leader in the research of treatments for both chronic and acute leukemias, she has developed several important therapies now regarded as the standard of care for chronic lymphocytic leukemia (CLL). She has served as the principal investigator for more than 40 funded clinical protocols and led the initial clinical research into ibrutinib (Imbruvica) for patients with chronic lymphocytic leukemia. She continues to research Bruton tyrosine kinase inhibitor in patients with CLL and small lymphocytic lymphoma.

O’Brien is the author of more than 900 articles in peer-reviewed journals, numerous book chapters and abstracts, she is also a past chair of the National Comprehensive Cancer Network guidelines panel on chronic myeloid leukemia. She was recently inducted into the 2020 Giants of Cancer Care® program by a panel of her peers in cancer research and clinical care.

She sees patients at the cancer center in Orange.