Cancer Has Afflicted People Since Prehistoric Times

The idea that cancer is a modern disease is a common misconception — one that the fossil record reveals to be untrue, as explained in this excerpt from The Cancer Chronicles: Unlocking Medicine's Deepest Mystery.

When Louis Leakey sat down to recount the discovery of what may be the earliest sign of cancer in the genus Homo, the first thing he remembered was the mud. It was March 29, 1932, midway through the Third East African Archaeological Expedition, and it had rained so long and so hard that it took an hour to drive the four miles from the campsite in Kanjera, near the shore of Lake Victoria, to the Kanam West fossil beds. By the time he and his crew had slogged their way through, they were covered with mud, and before long, Leakey, who was just beginning an illustrious career as an anthropologist, was on hands and knees scouring the ground for newly exposed bones.

He was coaxing the remains of an extinct pig from the muck when one of his Kenyan workers, Juma Gitau, walked over with a broken tooth he had just extracted from a cliff side. Deinotherium, Leakey noted, a prehistoric elephantlike creature that roamed Africa long ago. 

Gitau went back to look for more, and as he was scratching away at the cliff face, a heavy mass of calcified clay broke loose. He chopped it with his pick to see what was inside: more teeth, but not Deinotherium. These looked like what a dentist might recognize as human premolars, still set in bone, yet they came from a layer of sediment deposited, Leakey believed, in early Pleistocene time, about a million years ago.

The Kanam mandible quickly became a sensation. “Not only the oldest known human fragment from Africa,” Leakey proclaimed, “but the most ancient fragment of true Homo yet discovered anywhere in the world.” It was, he insisted, a direct precursor of us all.