Rena Callahan, MD

Associate Clinical Professor
Division of Hematology Oncology
UCLA David Geffen School of Medicine

Dr. Rena Callahan is a hematologist-oncologist who practices in Santa Monica and Santa Clarita and serves as an Associate Clinical Professor in the Division of Hematology Oncology at the UCLA David Geffen School of Medicine. She is actively involved in breast cancer research and treatment, with leadership roles in major clinical trials including VIKTORIA-1 and LIDERA, where she served as UCLA Principal Investigator. In June 2025, she also delivered an educational session at the ASCO Annual Meeting on the treatment of ER-positive metastatic breast cancer. Dr. Callahan is board-certified in hematology and medical oncology and cares for patients with a wide range of malignancies and blood disorders.
Dr. Callahan received her medical degree from the University of Pennsylvania School of Medicine, where she graduated with high honors from Alpha Omega Alpha. She completed her internal medicine and hematology/oncology training at UCLA. She received her Bachelor of Science degree in biology from Yale University.

Dr. Amy Steffe Lohmann
1977-2023

With deep sorrow, we share the news of the passing of our cherished co-chair, Dr. Amy Steffe Lohmann. Amy's strength, resilience, and boundless commitment to the fight against metastatic breast cancer have left an enduring impact on all of us.

Though she may have left us physically, her spirit will forever live on in the heart of the MetGala SCV. As we gather on September 9th, 2023, we will present a special tribute in honor of Amy's extraordinary contributions. This tribute will not only celebrate her remarkable journey but will also continue her legacy of raising awareness and funds for metastatic breast cancer research.
As we pay homage to Amy, we also invite you to support her two incredible children by contributing to their GoFundMe campaign. Your kindness will help secure their future and ensure that Amy's love continues to guide them.