Severe respiratory infections, including COVID-19 and influenza, may significantly increase the risk of developing lung cancer, even in individuals who have never smoked. This finding highlights the importance of preventative measures like vaccination and careful monitoring of patients recovering from serious respiratory illnesses.
A new study published on March 11 in the journal Cell, conducted by researchers at the University of Virginia (UVA) and based on both mouse models and hospital records, revealed an approximately 24% increased risk of lung cancer following a hospitalization for COVID-19. The research suggests that severe viral respiratory infections can leave a lasting inflammatory mark on the lungs, creating an environment conducive to cancer development.
“A severe case of COVID or the flu can leave the lungs in a state of sustained inflammation that makes it easier for cancer to establish itself later,” explained Jie Sun, a researcher at the UVA School of Medicine, in a statement. The study found that overwhelmed neutrophils and macrophages contribute to a “pro-tumoral” inflammatory environment, while epithelial cells and alveoli can undergo remodeling for years after the initial infection.
However, the research also offers a hopeful note: vaccination appears to largely prevent these harmful changes. “The good news is that vaccination largely prevents these detrimental changes favorable to cancer development in the lung,” Sun stated. This finding underscores the critical role of vaccination in protecting against long-term health consequences beyond the immediate threat of infection.
Researchers emphasize the need for altered post-infection monitoring protocols. “These results have vital immediate implications for how we monitor patients after a severe viral respiratory infection,” said Jeffrey Sturek, a physician-scientist at the University of Virginia and a collaborator on the project. “We’ve known for a long time that things like smoking increase the risk of lung cancer. The findings of this study suggest that we may need to think about severe viral respiratory infections the same way.”
The study’s findings suggest a potential shift in how healthcare professionals approach lung cancer screening, particularly for patients with risk factors like a history of smoking. For some high-risk patients, doctors already recommend close monitoring with routine chest CT scans to detect cancer early. Researchers found that the increased risk of 1.24 times was present regardless of smoking history or other health issues.
The increased risk extends to common respiratory illnesses beyond COVID-19. According to Top Santé, severe forms of the flu and COVID-19 can affect neutrophils and macrophages, immune cells designed to protect the body.
It’s also important to protect against other respiratory illnesses. Roswell Park notes that influenza, RSV, and COVID-19 can be particularly dangerous for people with cancer, potentially leading to increased hospitalization rates, treatment complications, and even death. Vaccines are available to significantly reduce the risk of severe illness and complications from these viruses.
