M.D. M.S.
Medical Oncologist
Pashtoon Kasi, MD is a nationally recognized cancer specialist who focuses on cancers of the gastrointestinal (GI) system. He now sees patients at the City of Hope® Lennar Foundation Cancer Center in Irvine, California, bringing world-class care to Orange County.
Inspired by his parents, who were also doctors, Dr. Kasi was drawn to cancer care early on. He was fascinated by how new treatments could lead to better outcomes for patients—and excited by the potential for even more breakthroughs in the future.
One of Dr. Kasi’s most important research efforts is known as the “NEST” clinical trial. In this study, he helped show that two immunotherapy drugs—botensilimab and balstilimab—can significantly reduce colorectal cancer tumors when given before surgery. This approach helps the body fight cancer more effectively and could offer new hope for curing certain cancers.
Dr. Kasi also works on cutting-edge technologies, such as liquid biopsies, which use blood samples to help diagnose and manage cancer. He often teams up with international scientists to keep pushing the boundaries of what’s possible in cancer care.
Before joining City of Hope, Dr. Kasi led research programs at Weill Cornell Medicine in New York. He also held faculty roles at the University of Iowa and Mayo Clinic, where he trained in oncology, hematology, and clinical research.
Dr. Kasi says it was his East Coast patients who introduced him to City of Hope. “They told me about the unique care available here and how it made a real difference,” he said. That inspired him to bring his talents to California.
In 2024, Dr. Kasi was honored with OncoDaily’s Yvonne Award for challenging the status quo in oncology. He’s also been recognized for his compassion and excellence during his training at Mayo Clinic.
Outside of work, Dr. Kasi is a father of two and finds time to support patient advocacy. He speaks Pashto and Urdu/Hindi and continues to look for ways to connect with and support his patients in every aspect of their care.