The oldest human tumor ever found — by more than 100,000 years — has been discovered in the rib of a Neanderthal.
The bone, excavated more than 100 years ago in Croatia, has been hollowed out by a tumor still seen in humans today, known as fibrous dysplasia. These tumors are not cancerous (they don't spread to other tissues), but they replace the weblike inner structure of a bone with a soft, fibrous mass.
"They range all the way from being totally benign, where you wouldn’t recognize them, to being extremely painful," said David Frayer, an anthropologist at the University of Kansas who reported the finding along with his colleagues today (June 5) in the journal PLOS ONE. "The size of this one, and the bulging of it, probably caused the individual pain." [Top 10 Mysteries of the First Humans]
The Neanderthal rib fragment measures just more than an inch long (30 millimeters). It was first unearthed between 1899 and 1905 in a cave known as the Krapina rock shelter in Croatia. This site held more than 900 Neanderthal bones dating back 120,000 to 130,000 years ago. Many of the bones display signs of trauma, and quite a few show post-mortem cutting marks, perhaps indicating cannibalism or some sort of ritual reburial.
Neanderthals (Homo neanderthalensis) were a human species closely related to modern humans (Homo sapiens). They died out approximately 30,000 years ago, though not without apparently interbreeding with Homo sapiens: Many modern-day humans carry Neanderthal DNA, suggesting the two species had sex.
In the 1980s, University of Pennsylvania researchers X-rayed the entire collection of bones found at Krapina, and they published a book in 1999 showing each radiograph. Most of those X-rays were quite high-quality, said Janet Monge, the keeper of physical anthropology at the University of Pennsylvania Museum, who participated in that project and the current study.
But there was one exception: One little rib fragment appeared "burned out" in the X-ray image, an overexposure that turned out to be due to the loss of inner bone in the specimen.
Now, the study researchers have returned to the rib, subjecting it to higher-quality X-rays and to microCT (computed tomography) scanning, which is similar to -- but higher-resolution than -- the types of scans doctors use to detect bone trauma in living patients.