Infectious diseases linked to 2 million cancer cases each year

Infectious agents are responsible for about 2 million cases of cancer each year, according to researchers from the International Agency for Research on Cancer in Lyon, France.

The researchers convened an expert working group in February 2009 to review infectious agents classified as carcinogenic to humans by the International Agency for Research on Cancer. They calculated the population attributable fraction (PAF) of these infectious agents worldwide and in eight geographical regions during 2008. The PAF is the proportion of new cancer cases that would have been prevented by an intervention after exposure to the infectious agent.

The infectious agents included Helicobacter pylori, hepatitis B virus, hepatitis C virus, Opisthorchis viverrini, Clonorchis sinensis, HPV, Epstein-Barr virus, human T-cell lymphotropic virus type 1, human herpes virus type 8 and Schistosoma haematobium.

There were 12.7 million new cancer cases in 2008, and the PAF was 16.1%, equal to about 2 million new cancer cases attributable to infections. In less developed countries, the PAF was 22.9% vs. 7.4% in more developed countries.

H. pylori, HBV, HCV and HPV were responsible for 1.9 cases, primarily gastric, liver and cervical cancers. In women, cervical cancer accounted for half of all cancers, and in men, liver and gastric cancers accounted for 80% of cancers.

“Although a full investigation of cancer death due to infection is beyond the scope of this report, we can estimate the mortality burden by applying PAFs to the 7.5 million cancer deaths that occurred in 2008,” the researchers wrote. “These calculations suggest that 1.5 million cancer deaths were attributable to infectious agents, or roughly one in five deaths due to cancer worldwide.”

References:

de Martel C. Lancet Oncol. 2012;doi:10.1016/S1470-2045(12)70137-7.

Disclosures:

The researchers report no relevant disclosures.