Not only does cancer predate the practice of medicine, but it may also predate the human species entirely. In 2016, archeologists in South Africa unearthed a large 1.7 million years-old bone fragment, ultimately revealed to be the toe bone of an ancient but unknown species of human dating back millennia. On that piece of bone, they discovered something else: a malignant tumor. It’s a stark reminder that, for as long as their profession has existed, oncologists have been studying and treating cancer. For many, it raises a frustrating question: After so many centuries of studying cancer, why haven’t we cured it yet? The answer is complicated.

Dr. Otis Brawley joins the Your Stories podcast to help us better understand what makes cancer such a complex and persistent adversary. In addition to being a professor of oncology at the Johns Hopkins University and a former chief medical and scientific officer of the American Cancer Society, Dr. Brawley is a member of Conquer Cancer’s Board of Directors and editor of The Cancer History Project, a free online resource dedicated to documenting the history of cancer in medicine. He talks with host Dr. Mark Lewis about why cancer has not yet been “cured” and about how our study and understanding of it has evolved over time.