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Danish pathologist Johannes Fibiger (Photo/Beijing News)

Award: The discovery that cockroaches are carcinogenic

A carcinogenic experiment that was hard to replicate.

At the beginning of the 1900s, Danish pathologist Johannes Fibiger was working hard to identify carcinogenic microorganisms. Having experienced more than 1000 failures, Fibiger began to suspect that cockroaches were the hosts of a carcinogenic microorganism. Therefore, he fed mice with cockroaches, and subsequently found tumors in the stomach of the mice.

This was the first time in history that anyone had succeeded in inducing cancer in experimental animals by physical methods. Fibiger published a paper on the results of his experiments in 1913, and was awarded the Nobel Prize for Medicine in 1926.

No other scientist could duplicate Fibiger's experiment, hence the accuracy of his experiment aroused tremendous skepticism.

Two years after Fibiger had published his paper, a Japanese scientist, Katsusaburo Yamagiwa, successfully induced skin cancer by painting crude coal tar on the inner surface of rabbits' ears. Yamagiwa's discovery received wide recognition, and went on to become the basis of cancer research. Encyclopedia Britannica's guide to Nobel Prizes in cancer research mentions Yamagiwa's work as a milestone without mentioning Fibiger.