Peyton Rous is awarded the Nobel Prize for tumor viruses

The hen and the filter

The Nobel Foundation's own account of the work is short. In 1910, Peyton Rous took material from a tumor in a hen and injected it into a healthy chicken. The healthy bird developed cancer. Rous concluded that the tumor contained something infectious, a virus, that could pass cancer from one animal to another.

The 1966 prize citation reads "for his discovery of tumour-inducing viruses." The prize was shared with Charles Brenton Huggins, honored for his work on hormonal treatment of prostate cancer. Rous was 87 by then. He had done the experiment 56 years earlier.

Why the wait

The Nobel Foundation is direct about the reason. The result could not be repeated in mammals, and it was long overlooked.

That is a fair summary of a long silence. A finding in chickens that would not transfer to rats or mice looked like a curiosity about birds, not a fact about cancer. Interest revived only when research showed that viruses can act by changing the genetic material of normal cells.

That was the real discovery hiding inside the first one. Cancer could begin with something inserted into a cell's own instructions.

What the idea became

The virus Rous found is now called Rous sarcoma virus, and the search for how it worked led to the genes that drive cancer. The general principle it opened up is now unremarkable. Cancer starts with changes in genes that control how cells grow and divide. Our page on what cancer is covers that basic mechanism.

NCI puts the infection route plainly. Certain infectious agents, including viruses, bacteria, and parasites, can cause cancer or raise the risk of it. Some viruses disrupt the signaling that normally keeps cell growth in check. Some infections weaken the immune system, leaving the body less able to handle other cancer-causing infections.

The list, as it stands

NCI names these infectious agents linked to cancer:

• Epstein-Barr virus.
• hepatitis B and hepatitis C viruses.
• HIV.
• human papillomaviruses.
• human T-cell leukemia/lymphoma virus type 1.
• Kaposi sarcoma-associated herpesvirus.
• Merkel cell polyomavirus.
• Helicobacter pylori.
• Opisthorchis viverrini, a liver fluke.
• Schistosoma hematobium, a parasitic worm.

A chicken experiment that would not replicate in mammals sits at the head of that list.

Why this is the most practical history on the site

Infection is the one cause of cancer you can sometimes remove.

NCI states that high-risk HPV types cause nearly all cervical cancers, along with most anal cancers and many oropharyngeal, vaginal, vulvar, and penile cancers. Vaccines prevent infection with the types responsible for most of those cancers. NCI notes the U.S. recommendation to vaccinate children at age 11 or 12, with vaccination possible from age 9 and up to age 26.

Chronic hepatitis B or C infection can cause liver cancer. NCI notes that infants in the United States and most other countries have been routinely vaccinated against hepatitis B since the 1980s, and that unvaccinated adults at increased risk should be vaccinated.

H. pylori is a bacterium that can cause noncardia gastric cancer and a stomach lining lymphoma called gastric MALT lymphoma. NCI says it can be detected and treated with antibiotics, and that roughly two-thirds of the world's population carries it, according to CDC estimates.

Our page on cervical cancer covers the screening side of the HPV story.

When to ask about this

Bring these up at a routine appointment rather than waiting for symptoms:

• HPV vaccination, if you or your children are in the age range NCI describes.
• hepatitis B vaccination, if you were never vaccinated and have any added risk.
• hepatitis C testing. NCI notes that CDC recommends it for everyone in the United States born from 1945 through 1965, and for other groups at increased risk.
• H. pylori testing, if you have ongoing stomach pain, indigestion, or a history of ulcers.

None of these is a cancer test. Each removes or reduces a cause. That is a different and often better place to intervene.

What this does not mean

• Cancer is not contagious. Some infections that raise cancer risk are transmissible, which is not the same thing.
• Most people carrying these agents never develop cancer. H. pylori is carried by a large share of the world's population.
• Rous sarcoma virus infects chickens. It is not a human pathogen, and the discovery mattered for what it revealed about genes, not as a human threat.
• Vaccination and treatment lower risk. They do not remove it, and they do not replace screening where screening exists.

Sources

• NobelPrize.org: The Nobel Prize in Physiology or Medicine 1966
• NobelPrize.org: Peyton Rous — Facts
• NCI: Infectious Agents and Cancer
• NCI: What Is Cancer?

How this page was made

An AI-assisted editorial system helped prepare this page. This article has not been reviewed by a healthcare professional unless a named reviewer is specifically shown. Cancer Explained is published by the National Cancer Information Foundation as a nonprofit-oriented public-interest education project. It is not a diagnostic service, does not recommend treatments, and is not for emergencies.

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