The largest number of cases was attributable to H pylori (n=760,000; PAF 4%); followed by HPV (n=750,000, 4%), EBV (n=260,000, 1%) HCV (n=160,000, <1%) and KSHV (n=35,000, <1%). The corresponding ASIR for all infections combined was 22.7 cancer cases per 100,000 person-years.HPV had the highest ASIR for infection-attributable cases (7.7), followed by H pylori (6.9), HBV (3.4), EBV (2.6), HCV (1.5) and KSHV (0.4).
The investigators found the largest number of infection-attributable cancer cases in eastern Asia (999,000 cases, 42% of global total); with the region having a PAF of 15% and an ASIR of 31.9 per 100,000 person-years.Other regions with higher PAFs and ASIRs than the global average included sub-Saharan Africa, central and Eastern Europe and southeastern Asia.
Rumgay and colleagues point out that despite progress in vaccination and screening, infection-related cancers remain a global challenge, "with persistent inequities especially impacting low-income and middle-income countries."
What You Need to Know
About 2.3 million new cancer cases worldwide in 2024, or 1 in 8 of all new cases, were attributable to infection, according to the first global analysis to include HIV in its estimate.
Helicobacter pylori (760,000 cases) and HPV (750,000 cases) caused the largest share of infection-attributable cancers, and eastern Asia carried the heaviest regional burden, with 42% of the global total.
Because most of these infections can be prevented or treated before cancer develops, the investigators call for wider access to HPV vaccination, H pylori screen-and-treat programs, and long-acting injectable HIV PrEP, especially in low- and middle-income countries.
They point to H pylori as a major cause of cancer globally, despite improved sanitation programs and reduced incidence of intrafamilial transmissions. They recognize several recent initiatives to address the persistently high incidence, however, including population-based gastric cancer screening endoscopy programs in Japan, South Korea and China; and H pylori "screen-and-treat” programs in several countries in Europe.
With the direct association of cervical cancer to HPV, Rumgay and colleagues urge greater access to HPV vaccine in low- and middle-income countries, "if increasing inequalities in future cervical cancer burden are to be avoided".
Noting that HIV-attributable cancer burden is highest in southern and eastern Africa, the investigators commend the 2025 WHO approval of long-acting, injectable pre-exposure prophylaxis. PrEP holds great potential for primary prevention by reducing HIV transmission and HIV attributable cancers, they indicate, "if integrated into a comprehensive combination approach spanning condom promotion, HIV testing, and harm reduction services for people who inject drugs."
The study was characterized as a "staggering new analysis" in one health center press release, in which medical faculty emphasized that preventable infections are a substantial but often overlooked cause of cancer.3
"This recent Lancet data is a profound reminder that a significant portion of our global cancer burden is fundamentally preventable," stated David Greenberg, MD, Hematology Oncology, Hackensack Meridian Health, Neptune, New Jersey."We have historically siloed infectious diseases and oncology, but they are deeply intertwined.By shifting toward aggressive infection control, we can literally vaccinate and treat our way out of millions of future cancer diagnoses."
References
1. Rumgay H, Georges D, Huang Y, et al. Global burden of cancer attributable to infections in 2024: A worldwide incidence analysis. The Lancet Oncology. 2026; 27:1237-1248.
2. International Agency for Research on Cancer. IARC monographs on the evaluation of carcinogenic risks to humans volume 100B: biological agents. International Agency for Research on Cancer. 2012.
3. Hackensack Meridian Health. Newswise Press Release. The hidden cause of 2+ million cancer cases. 2026, September 30. https://www.newswise.com/articles/the-hidden-cause-of-2-million-cancer-cases.
