A recent study published in The Lancet Oncology reveals that infections play a significant role in causing cancer, with approximately one in eight new cancer cases globally attributed to infectious agents. Research conducted by The International Agency for Research on Cancer (IARC) identified about 2.3 million new cancer cases in 2024 linked to infections, making up 12% of all new cases.
Among the infectious agents, Helicobacter pylori was found to be responsible for the highest number of cancer cases globally, particularly stomach cancer cases in eastern Asia, totaling around 760,000 cases. Human papillomavirus (HPV) followed closely, contributing to nearly 750,000 new cases worldwide, with a high prevalence in sub-Saharan Africa. Hepatitis B virus (HBV) and hepatitis C virus (HCV) were also associated with a notable number of liver cancer cases.
The study expanded the list of cancers linked to infections, including 16 additional types. Researchers highlighted the increasing evidence of infectious agents like HIV and Merkel cell polyomavirus as cancer-causing agents, emphasizing the need for preventive measures.
Epstein-Barr virus (EBV) was identified as a significant contributor to cancer cases globally, leading to various types of cancers, such as nasopharyngeal cancer and Hodgkin’s lymphoma. The study underscored the urgent need for strategies to address infections like EBV that are associated with chronic diseases.
Regional disparities in cancer cases related to infections were noted, with high-income countries showing better outcomes due to established screening and vaccination programs. In North America, infections like Helicobacter pylori and HPV are major contributors to cancer cases.
In Canada, a 2019 study estimated that infections account for about four percent of cancer cases. While the prevalence of infection-related cancers is lower in Canada, these infections still lead to over 7,000 cancer diagnoses annually. Efforts to increase vaccination rates and screening programs are crucial to combat infections like HPV, a key focus in Canada’s cervical cancer elimination plan.
Helicobacter pylori remains a significant concern, with efforts underway to implement universal screening programs for early detection and treatment. Although stomach cancers may not receive as much attention as other cancers, targeted screening programs for high-risk groups are seen as crucial in preventing unnecessary deaths.