Marisa C. Weiss

Marisa C. Weiss, M.D. is the founder, president and guiding force behind Breastcancer.org, the world's most trafficked online resource for medically-reviewed breast health and breast cancer information, reaching over 8 million visitors per year. A breast cancer oncologist with twenty years of active practice in the Philadelphia region, Dr. Weiss is regarded as a visionary advocate for her innovative and steadfast approach to informing, empowering, and treating patients with breast cancer.

Dr. Weiss currently practices at Lankenau Hospital, part of the Main Line Health Hospitals of the Thomas Jefferson University Health System in the Philadelphia-area, where she serves as director of breast radiation oncology and director of breast health outreach. After attending the University of Pennsylvania for her undergraduate studies, medical school, residency, and laboratory research fellowship, Dr. Weiss became an assistant professor in Penn's Radiation Oncology Department. In 1992, she established her clinical practice in the Main Line Health System.

Dr. Weiss lives in Wynnewood, Pennsylvania, with her husband, a pediatrician and avid fisherman, their three children, and two dogs.