Periodically you hear news stories about viruses such as avian influenza and infectious bronchitis virus affecting chickens and other poultry, and often with devastating effects. What you may not know, however, is that exposure to poultry viruses has been associated with an increased risk of various human cancers, including penis cancer (aka, penile cancer).
Penis cancer is relatively uncommon. According to the American Cancer Society, about 2,030 new cases of penile cancer will be diagnosed in 2016 and 340 men will die of the disease. Traditional risk factors include not being circumcised, presence of human papillomavirus (HPV), age older than 60, having phimosis, poor personal hygiene, having many sexual partners, and tobacco use.
According to investigators who have been exploring the relationship between poultry viruses and cancer, “Humans are commonly exposed to viruses that naturally infect and cause cancer in food animals such as poultry that constitute part of the biological environment. It is not known if these viruses cause cancer in humans.”
What’s the link between chickens and penis cancer?
In an early 2010 study from the University of North Texas Health Science Center, experts evaluated information concerning 2,580 individuals who worked in poultry slaughtering and processing plants. When they compared cancer mortality in this group against the general population, they found an excess of cancers of the nasal cavities, pharynx, esophagus, rectum/anus, liver, and intrabiliary system as well as lymphoid leukemia, myelofibrosis, and multiple myeloma.
From these findings, the authors hypothesized that viruses found in poultry, as well as exposure to fumes in the processing plants, could have a role in the development of at least some of these cancers.
A subsequent study conducted by some of the same experts at the same university reported on their findings using a larger population: 20,132 workers in poultry slaughtering and processing facilities. Once again, mortality was compared with that of the general population. While the investigators found an increased risk of many of the same cancers named in the earlier study, two new cancers were identified: penile cancer and cervical cancer. In the case of penile cancer, the experts found an eightfold higher risk of developing and/or dying of penile cancer among the men in the study.
The authors concluded that their findings provided “evidence that a human group with high exposure to poultry oncogenic [cancer causing] viruses has increased risk of dying from several cancers.” One important question that arises from these findings is whether non-occupational exposure to poultry viruses, such as when handling raw poultry and/or eating poultry that has not been cooked thoroughly, also presents an increased risk of cancer. That question, along with others relating to the risk of penile cancer associated with exposure to poultry, are for future research.
Johnson ES et al. Mortality from malignant diseases–update of the Baltimore union poultry cohort. Cancer Causes & Control 2010 Feb; 21(2): 215-21
Johnson ES et al. Cancer mortality in poultry slaughtering/processing plant workers belonging to a union pension fund. Environmental Research 2010 Aug; 110(6): 588-94