Infections Linked to Over 2 Million Cancer Cases Globally

Infections were linked to over 2 million new cancer cases globally in 2024, according to an analysis of worldwide cancer incidence published in The Lancet Oncology. This figure represents approximately 12.7% of all new cancer cases diagnosed in that year, underscoring the significant burden of infection-related cancers. The study, which synthesized data from various sources including the Global Burden of Disease (GBD) 2021 study, identified specific pathogens responsible for a substantial proportion of these cases. Among the most impactful were human papillomavirus (HPV), hepatitis B virus (HBV), hepatitis C virus (HCV), and Helicobacter pylori.

HPV was identified as the leading infectious agent, contributing to an estimated 690,000 new cancer cases in 2024. This primarily includes cervical cancer, but also cancers of the anus, oropharynx, penis, vagina, and vulva. HBV and HCV infections were collectively responsible for an estimated 530,000 new liver cancer cases, with HBV accounting for a larger share. H. pylori, a bacterium commonly associated with stomach ulcers, was linked to an estimated 430,000 new stomach and non-cardia gastric cancers. Epstein-Barr virus (EBV) was also highlighted, contributing to cancers such as nasopharyngeal cancer, stomach cancer, and certain lymphomas.

The analysis emphasized that the majority of these infection-attributable cancers were preventable. The researchers pointed to existing and emerging interventions, such as HPV vaccination, hepatitis B vaccination, and screening and treatment for HBV, HCV, and H. pylori. They also noted that these infections disproportionately affect lower-income countries, where access to preventive measures and healthcare is often limited. For instance, the study indicated that over 70% of infection-attributable cancers occurred in low- and middle-income countries. This highlights a critical global health inequity that needs to be addressed through targeted public health strategies and increased investment in infectious disease prevention and control programs.

The findings serve as a critical call to action for global health organizations, governments, and healthcare providers to prioritize and scale up efforts to prevent and control infectious agents known to cause cancer. This includes expanding vaccination coverage, improving access to diagnostics and treatments for chronic viral infections, and implementing public health campaigns to raise awareness about the link between infections and cancer. The study's authors stressed that by effectively tackling these preventable infections, a significant reduction in the global cancer burden is achievable, potentially saving millions of lives in the coming decades and alleviating pressure on healthcare systems worldwide.