Hepatitis C is a risk factor for mouth and throat cancer, say researchers from the University of Texas MD Anderson Cancer Center (abstract here).
Hep C is a serious viral infection of the liver, mainly transmitted through infected blood via shared needles and accidental needle sticks or through sexual contact (here). It can cause liver damage and failure, and it is a risk factor for liver cancer. Hep C kills 19,000 Americans yearly, but there are effective treatments (here).
The researchers, led by first author Parag Mahale, had access to 34,500 blood samples from MD Anderson cancer patients treated between 2004 and 2014. The researchers divided Hep C patients into two groups: those who had cancers of the head and neck region (n = 609) and controls with cancers of the lung, esophagus and bladder (n = 1,143). They looked for differences in Hep C infection rates.
Mahale and colleagues found that about 14% of people with mouth or throat cancer were infected with Hep C, which is about twice the rate as controls (OR = 2.0, 95% confidence interval, CI = 1.04 – 4.01). The association was somewhat higher in patients who had mouth or throat cancer and who were infected with human papillomavirus, HPV (OR = 3.0, CI = 1.3 – 6.8).
I have previously discussed the emerging evidence for HPV as a risk factor for mouth and throat cancer (here and here). The new research suggests that Hep C may also play a causative role.