A study of ancient remains has found that cancer is a man-made disease fuelled by pollution and changes to diet and lifestyle.
Tumours were rare until recent times when pollution and poor diet became issues, a review of mummies, fossils and classical literature found.
Despite slivers of tissue from hundreds of Egyptian mummies being rehydrated, just one case of cancer has been confirmed. This is even though tumours should be better preserved by mummification than healthy tissues.
"The virtual absence of malignancies in mummies must be interpreted as indicating their rarity in antiquity. This indicates that cancer-causing factors are limited to societies affected by modern industrialization," The Daily Mail quoted researcher Michael Zimmerman, a visiting professor at Manchester University, as saying.
The ancient Greeks were probably the first to define cancer as a specific disease and to distinguish between benign and malignant tumours.ut researchers said it was unclear if this signalled a real rise in the disease, or just a greater medical knowledge.
"There is nothing in the natural environment that can cause cancer," co-researcher Professor Rosalie David said.
"So it has to be down to pollution and changes to diet and lifestyle. The important thing about our study is that it gives a historical perspective to this disease," David added.
"Data from across the millennia has given modern society a clear message - cancer is man-made and something that we can and should address."