Hepatitis C virus (HCV), a virus linked to liver cancer and non-Hodgkin’s lymphoma, also has a strong association with head and neck cancers, according to a new study conducted by The University of Texas MD Anderson Cancer Center and published in the Journal of the National Cancer Institute. The study suggests that screening for HCV in patients with head and neck cancer is very important because HCV seems to be associated with nonoropharyngeal head and neck cancers and HPV (human papillomavirus)-positive oropharyngeal cancers. (Oropharyngeal refers to the middle part of the throat.)
Harrys A. Torres, MD, lead author of the study and associate professor of infectious disease, infection control, and employee health at MD Anderson, said the impetus behind the study came when he noticed several HCV patients in his cancer clinic had head and neck cancer.
“What I was expecting to see in that clinic was a significant number of patients with hepatocellular carcinoma (HCC, a type of liver cancer), and probably non-Hodgkin’s lymphoma, because these are the top two cancers associated with HCV. However, I started seeing several patients come in with head and neck cancer, and I didn’t know why.”
Dr. Torres looked at patient data from 34,545 MD Anderson cancer patients, 409 of whom had head and neck cancers. The data revealed between 14 to 20 percent of head and neck cancer patients (depending on the type of head and neck cancer) had tested positive for HCV antibodies.
“Around 1.5 percent of the United States population is infected with hepatitis C, so these findings are significantly higher,” said Dr. Torres. In fact, the study revealed patients with HCV infection are two to five times more likely to have a head and neck cancer than other tobacco-related cancers.
Since HCV is a curable infection when treated with the latest drugs on the market, treating for HCV could be an opportunity to prevent or improve the outcome of HCV-associated cancers.
“If we identify hepatitis C early and we treat these patients, there is a very good chance we are going to reduce the number of all these cancers associated with the virus and reduce the potential for complications like hepatic toxicity (chemical liver damage) during the treatment of their existing cancer,” said Dr. Torres. “That has been proven in HCC. We know that when we treat hepatitis C the incidence of HCC will decrease. It is the same for non-Hodgkin’s lymphoma. It remains to be explored whether curing the infection reduces the risk of head and neck cancers, as we do not know if this epidemiological association is causal, i.e. whether the virus directly causes head and neck cancers.”
Dr. Torres said the challenge now is getting at-risk Americans into clinics to be screened for HCV, a disease which for the most part has no symptoms.
“That is one of the major problems with HCV — patients are not aware they have it. When patients do ultimately have symptoms, most of the time it’s too late for curable treatment. They have developed advanced cirrhosis (liver damage) and treatment is not even possible because it is so advanced. That is why screening is so important for early detection of this infection.”
The Centers for Disease Control and Prevention recommends all baby boomers (those born between 1945 through 1965) be tested once for HCV even if they do not have any other risk factors, because 75 percent of all HCV infections occur in baby boomers. Risk factors for HCV infection include injection drug use, having received a blood or organ donation before 1992, HIV infection, and certain medical conditions.
Promoting this testing recommendation is also a focus of Texas HepCA, a team of oncologists and hepatologists (cancer and liver specialists) working with the Texas Medical Association’s (TMA’s) Committee on Cancer and TMA Foundation (TMA’s philanthropic arm) to increase awareness of and education about HCC. HCV is a known cause of HCC due to the damage it inflicts on the liver in the form of cirrhosis.
Dr. Torres cautioned that this study does not prove HCV directly causes head and neck cancers, but it is the first study to reveal a strong association between the two.
“Our study is just the first step to address knowledge gaps related to the oncologic (cancer) impact of HCV. The next step is to do further research,” he said.
He also stressed that tobacco, excessive alcohol use, and HPV infection remain the most important risk factors for head and neck cancers. “All people — with or without HCV infection — should consider lifestyle changes to reduce the risk of these cancers.”