Overview

• Mouse studies showed influenza or SARS-CoV-2 infection awakened latent breast cancer cells in the lungs, producing visible metastatic lesions within two weeks.
• Molecular analyses identified interleukin-6 released during the immune response as the critical signal driving dormant tumor cell reactivation and growth.
• UK Biobank and Flatiron Health data linked COVID-19 infection to double the rate of cancer-related deaths and over a 40% increase in lung metastasis risk among breast cancer patients.
• Researchers stress that common respiratory viruses do not cause cancer but can increase the risk of recurrence in patients with previously dormant tumor cells.
• Investigators are now evaluating IL-6 inhibitors and reinforcing flu and COVID-19 vaccination recommendations to reduce post-infection metastasis in survivors.