Results from a new research study suggest that a spike in infections such as influenza could be linked to the risk of developing certain cancers.
The study, published in Cancer Immunology Research, followed over 50,000 individuals who experienced influenza, gastroenteritis, hepatitis, and pneumonia infections over a 7 year period to look for correlations with cancer diagnoses. The researchers found that an increased rate of infection in the “pre-cancerous” phase correlated with an eventual cancer diagnosis.
Cancer can develop in an inflammatory environment caused by infections, immunity disruption, exposure to chemical carcinogens, or chronic or genetic conditions, says Shinako Inaida, corresponding author of the study.
“An individual’s immunity is thought to be a factor in the development of cancer, but additional research is needed to understand the relationship [between] precancerous immunity, infections, and cancer development. This information may contribute to efforts to prevent or detect cancer.”
Interestingly, their data suggested that different infection types were associated with the subsequent development of specific cancers. Subsets of patients who went on to develop male germ cell cancers, for example, had a higher incidence of influenza. On the other hand, stomach cancer patients had a greater chance of having pneumonia prior to the diagnosis.
Inflammation is likely the root of this link between infections and cancer. Inflammation is a double-edged sword: while it helps us eliminate invading pathogens and dead cells, too much of it fuels cancer development, aiding tumor growth and spread throughout the body.
This and ongoing studies looking into the links between immunity, inflammation and cancer development could pave the way for improved diagnostic methods and earlier interventions.