Viral Infections May Reactivate Dormant Breast Cancer Cells, Increasing Risk of Recurrence and Metastasis

Strategic Insights -

New research published in Nature has found that respiratory viruses like Covid-19 and flu may reactivate breast cancer cells that have settled in the lungs of mice, increasing the risk of breast cancer recurrence and metastasis. The study, led by James DeGregori, a professor of biochemistry and molecular genetics at the University of Colorado School of Medicine, also found that women with a history of breast cancer who caught Covid-19 were nearly 50% more likely to develop metastatic breast cancer in their lungs.

Key Takeaways:

  • The study found that respiratory viruses can reactivate dormant breast cancer cells in mice, leading to a 100-fold surge in levels of previously dormant cancer cells in the lungs.
  • Women with a history of breast cancer who caught Covid-19 were nearly 50% more likely to develop metastatic breast cancer in their lungs compared to those who tested negative for the virus.
  • The researchers also found that these women had almost double the risk of dying from cancer, with the risk being even greater in the months following infection.
  • The study's findings highlight the importance of regular Covid and flu vaccinations for those who have had breast cancer.
  • Immunologists say that widespread inflammation triggered by a viral infection can reawaken dormant cancer cells, while suppressing the immune system's ability to attack and destroy cancer.
  • Experts warn that the data is not sufficient to prove a direct link between Covid-19 and metastatic cancer in humans, and that more research is needed to understand the relationship between viral infections and cancer recurrence.

Statistics:

  • 1 in 5 women with breast cancer that is treated successfully develops secondary tumours in other parts of the body - sometimes decades later.
  • 50% increase in risk of developing metastatic breast cancer in the lungs for women with a history of breast cancer who catch Covid-19.
  • 100-fold surge in levels of previously dormant breast cancer cells in the lungs of mice after respiratory virus infection.
  • Almost double the risk of dying from cancer for women with a history of breast cancer who catch Covid-19.

Sources:

  • DeGregori, J. et al. (2022). Respiratory viruses reawaken dormant cancer cells in mice. Nature. [1]
  • DeGregori, J. (Interview with Good Health). [2]
  • PROFESSOR Kefah Mokbel (Interview with Good Health). [3]
  • Dani Edmunds (Interview with Good Health). [4]