MedicalResearch.com Interview with:
Harrys A. Torres, MD, FACP, FIDSA
Director of Hepatitis C Clinic
Department of Infectious Diseases, Infection Control and Employee Health
The University of Texas MD Anderson Cancer Center
Houston TX 77030
Medical Research: What is the background for this study? What are the main findings?
Dr. Torres: Hepatitis C virus (HCV) is an oncogenic virus and is associated with an increased risk of liver cancer and certain types of non-Hodgkin lymphomas. In 2009, at MD Anderson Cancer Center, we set up the first clinic in the United States, and probably in the world, specifically devoted to managing HCV infection in cancer patients. In the clinic, we expected to see a number of patients with liver cancers and non-Hodgkin’s lymphoma, as these have documented associations with HCV. Unexpectedly, we saw a high number of HCV-infected patients with head and neck cancers, and wondered whether there was an undiscovered association between having the infection and head and neck cancers. To explore this, we conducted a case-control study using 409 head and neck cancer subjects (164 oropharyngeal, 245 non-oropharyngeal [oral cavity, nasopharynx, larynx] cancers) and 694 control subjects with other smoking-associated cancers (378 lung, 168 esophagus, and 148 urinary bladder cancers), and compared the prevalence of HCV infection in the two groups. We observed a high prevalence of HCV infection in oropharyngeal (14%) and non-oropharyngeal (20%) cancer patients when compared to control subjects (6.5%). After adjusting for confounders such as smoking, alcohol intake, and socioeconomic status, HCV-infected individuals were 2.04 times more likely to have oropharyngeal cancers and 2.85 times more likely to have non-oropharyngeal cancers. Of note, HCV was associated only with patients with oropharyngeal cancers that tested positive for human papilloma virus, which is one of the main virus linked with increased risk of oropharyngeal cancers.
Medical Research: What should clinicians and patients take away from your report?
Dr. Torres: It is critical to understand that HCV impacts not only the liver, but is a systemic infection. There has been increasing evidence that links HCV with several non-liver cancers. Our study suggests that certain head and neck cancers are one of the category of cancers associated with HCV infection. Since HCV infection is chronic and most people infected with the virus are not aware that they are infected, oncologists who see patients with head and neck cancers should consider testing patients for HCV infection. Certainly, those individuals born between 1945 and 1965 (“baby boomers”) should be tested for HCV according to the CDC guidelines. Conversely, physicians managing patients with HCV-infection should be aware that they may be at an increased risk for non-liver cancers such as those of the head and neck region. With the new medications available, HCV is considered to be a curable disease with more than 90% success rate. HCV treatment should be offered to infected individuals whenever possible.
Medical Research: What recommendations do you have for future research as a result of this study?
Dr. Torres: As with all observational studies, our study has its own limitations. Thus, replication of these results in a larger setting and with cancer-free controls is necessary. We also do not know if this association is causal, i.e. whether the virus directly causes head and neck cancers. Treatment with antiviral drugs may prevent some cancers (e.g., liver cancers and non-Hodgkin’s lymphoma) from ever developing in infected patients. It remains to be explored whether curing the infection reduces the risk of head and neck cancers. On the other hand, for patients with HCV and some indolent non-Hodgkin’s lymphoma, is now recommend that the HCV be treated first, given that it is curable. In some cases, the lymphoma has gone into remission upon treating the HCV with antiviral therapies, whether HCV-infected head and neck cancer patients have better cancer-related outcomes after HCV therapy remains to be determined.
Our study, published in the Journal of the National Cancer Institute, is just the first step to address knowledge gaps related to the oncologic impact of HCV and generates an area of great interest for future research study. With these findings, MD Anderson plans to screen and treat all head and neck cancer patients with HCV and follow their outcomes.
Association Between Hepatitis C Virus and Head and Neck Cancers
JNCI J Natl Cancer Inst (2016) 108 (8): djw035 doi: 10.1093/jnci/djw035
Parag Mahale, Erich M. Sturgis,David J. Tweardy, Ella J. Ariza-Heredia and
Harrys A. Torres