Cancer has existed for at least 76 million years. The oldest confirmed case is an osteosarcoma, a type of bone cancer, found in the fossilized leg bone of a plant-eating horned dinosaur called Centrosaurus apertus. Far from being a modern disease, cancer is a vulnerability woven into the basic biology of multicellular life.
Cancer in Dinosaurs and Early Humans
That 76-million-year-old Centrosaurus fossil, discovered in what is now Canada, was the first malignant tumor ever confirmed in a dinosaur through microscopic tissue analysis. The finding, published by the American Association for Cancer Research, demonstrated that unregulated cell growth is not something created by pollution, processed food, or modern lifestyles. It is a fundamental risk that comes with having cells that divide.
Moving forward in the evolutionary timeline, the earliest known tumor in a human relative appeared roughly 1.98 million years ago. Researchers examining the foot bones of Australopithecus sediba, an extinct hominin found at the Malapa site in South Africa, identified a benign bone-forming tumor called an osteoid osteoma. This species lived more than a million years before modern humans existed, yet its cells were already susceptible to abnormal growth.
Ancient Civilizations Knew About Cancer
The earliest written descriptions of cancer come from ancient Egypt. Two medical texts, the Edwin Smith and George Ebers papyri, contain references to tumors written around 1600 B.C. and are believed to draw on sources as old as 2500 B.C. These documents show that Egyptian physicians recognized cancer as a distinct condition thousands of years ago, even if they had no effective way to treat it.
Archaeologists have since confirmed those written accounts with physical evidence. Studies of Egyptian mummies buried between 1,500 and 3,000 years ago have uncovered six cases of cancer, including a toddler with leukemia, a man in his 50s with rectal cancer, and individuals with tumors possibly linked to human papillomavirus (HPV). HPV itself evolved in Africa long before Homo sapiens appeared, meaning the virus-cancer connection is ancient as well.
How Cancer Got Its Name
The word “cancer” traces back to the Greek physician Hippocrates, who lived around 400 B.C. He used the terms “carcinos” and “carcinoma” to describe tumors, drawing on the Greek word “karkinos,” meaning crab. The name likely came from the appearance of blood vessels radiating outward from a tumor, resembling a crab’s claws. That imagery stuck, and the Latin translation, “cancer,” became the word we still use today.
About five centuries later, the Roman physician Galen built on Hippocratic theory by attributing cancer to an excess of “black bile,” one of the four bodily fluids that ancient physicians believed governed health. Galen taught that thick black bile caused incurable cancers, while thinner bile was responsible for treatable tumors. This explanation was wrong, but it dominated medical thinking for more than a thousand years.
Cancer in the Medieval World
For a long time, historians assumed cancer was rare before the modern era. Recent research from the University of Cambridge overturned that assumption. Using X-rays and CT scans on skeletal remains from medieval Britain, researchers found that 9 to 14 percent of adults had cancer at the time of their death. That is roughly ten times higher than previous estimates, which had relied only on visible damage to bones and missed cancers in soft tissue that had long since decomposed.
Medieval physicians had almost nothing effective to offer. The French Renaissance surgeon Ambroise Paré called cancer “Noli me tangere,” meaning “do not touch me,” and warned that operating on tumors rarely led to healing. Patients who could afford treatment might receive poultices, cauterization, or pain-relieving remedies, but as one researcher put it, “there was very little doctors would have had that was actually helpful.” Despite significant advances in anatomy during the Renaissance, cancer treatment remained essentially stagnant.
Why Cancer Is More Common Now
Cancer rates today are substantially higher than in the medieval period, but the gap is smaller than most people think. In modern Britain, 40 to 50 percent of people have cancer by the time they die, making it roughly three to four times more common than in medieval populations (not the hundredfold difference older estimates suggested).
Several factors explain the increase. The most significant is lifespan. People in the medieval period rarely lived past their 50s or 60s, and cancer risk climbs sharply with age. Every additional decade of life gives cells more time to accumulate the mutations that drive tumor growth. Beyond aging, tobacco use, which arrived in Britain in the 16th century, introduced a powerful carcinogen to entire populations. Industrial pollutants that became widespread starting in the 18th century added further DNA-damaging exposures. Long-distance travel may have also spread cancer-causing viruses to regions where they previously didn’t exist.
None of this means cancer is a “modern” disease. It means that modern life created conditions where more people live long enough, and encounter enough carcinogens, for cancer to develop. The biological machinery behind it has been around since before the dinosaurs.
When Science First Saw Cancer Cells
For most of human history, cancer was understood only by what physicians could see and feel from the outside. That changed in 1838, when the German scientist Johannes Müller published a systematic analysis of the microscopic features of both benign and malignant tumors. Müller and his assistants in Berlin had been collecting and examining tissue samples under microscopes since 1833, and his monograph was the first work to describe what cancer actually looked like at the cellular level. This marked the beginning of tumor pathology as a scientific discipline, shifting cancer from a mystery explained by “bad fluids” to a disease that could be studied, classified, and eventually understood at the molecular level.