Hepatitis C virus (HCV), which has long been associated with primary liver cancer and non-Hodgkin lymphoma, has been linked less conclusively to several other cancers, including those of the head and neck. When researchers at The University of Texas MD Anderson Cancer Center noticed a high rate of HCV infection in their head and neck cancer patients, the researchers launched several studies to explore the relationship between HCV and head and neck cancers. Their findings could change standard practices for HCV screening and treatment in patients with cancers of any type.
HCV as a comorbidity in cancer patients has long been a concern at MD Anderson. The institution was among the first cancer hospitals in the world to establish a clinic for HCV treatment, in 2009, and to implement HCV screening for all new patients, in 2016. As a result, MD Anderson has acquired a wealth of data on patients with cancer and HCV.
“When we started to see that, compared with some other cancers, a higher proportion of patients with head and neck cancers tested positive for HCV, we wanted to find out why,” said Harrys Torres, M.D., an associate professor in the Department of Infectious Diseases, Infection Control, and Employee Health and the director of the HCV clinic. So far, Dr. Torres and colleagues have found that HCV is associated with head and neck cancers.
“It’s a new, exciting area of research,” Dr. Torres said. “I believe our ongoing studies will find additional important and clinically significant information.”
HCV and cancer development and outcomes
Dr. Torres and colleagues including Erich Sturgis, M.D., M.P.H., a professor in the Department of Head and Neck Surgery, conducted a retrospective study of 409 patients with head and neck cancers who were tested for HCV between 2004 and 2014. Analyzed as controls were 694 patients with other tobacco-related cancers—specifically those of the lung, esophagus, or bladder—who were tested for HCV during the same period.
The researchers found that both oropharyngeal and nonoropharyngeal head and neck cancers were associated with HCV seropositivity. Because human papillomavirus (HPV) infection is a factor in the pathogenesis of oropharyngeal cancer, the researchers conducted a subgroup analysis of HCV and HPV status in patients with oropharyngeal cancer. HCV seropositivity was associated with HPV-positive but not HPV-negative oropharyngeal cancers.
“HCV and HPV have common oncogenic pathways,” Dr. Torres said. “Both viruses act on the TP53 and retinoblastoma tumor suppressor genes. That may explain synergism between the two viruses to cause oropharyngeal cancer.” However, he added, there is much more to be learned about the relationship between the two viruses.
Dr. Torres and colleagues also investigated the effect of HCV infection on survival in patients with oropharyngeal and nonoropharyngeal head and neck cancers. The results of their study of patients with oropharyngeal cancer were recently accepted for publication in Cancer, and the researchers plan to have the results of their study of patients with nonoropharyngeal head and neck cancers ready to present at the 2018 meeting of the American Society of Clinical Oncology (ASCO).
In their study of survival in patients with oropharyngeal cancer, the researchers reviewed the records of patients who were tested for HCV at MD Anderson from 2004 to 2015. The 5-year overall and progression-free survival rates were significantly higher for HCV-negative patients than for HCV-positive patients (see graph above). Furthermore, among HCV-positive patients with oropharyngeal cancer, the 5-year overall and progression-free survival rates were significantly higher for those who underwent antiviral treatment for HCV than for those who did not.
“HCV not only is epidemiologically linked to head and neck cancer but also seems to affect the survival of some of these patients,” Dr. Torres said.
Implications for physicians
A group of ASCO collaborators, including Dr. Torres and Jessica Hwang, M.D., M.P.H., an associate professor in the Department of General Internal Medicine, are developing an educational statement for oncologists about the importance of HCV in patients with any type of cancer. “First, we are advising physicians to screen cancer patients for HCV,” Dr. Torres said. “Second, we’re urging physicians to refer HCV-positive patients for antiviral therapy.” He added that many cancer patients who are found to have HCV are able to undergo HCV treatment and cancer treatment at the same time.
Treating HCV in patients with non-Hodgkin lymphoma is known to improve oncologic outcomes. In fact, some patients with indolent lymphoma experience a complete remission of their cancer after antiviral treatment for HCV. The benefits of HCV treatment are not as well known in patients with other cancers, but Dr. Torres said that curing the virus will likely have long-term effects beyond the prevention or slowing of cirrhosis.
Treating HCV in cancer patients may also prevent second primary cancers (e.g., primary liver cancer, non-Hodgkin lymphoma) from arising. Dr. Torres has begun researching this topic in collaboration with colleagues including Ernest Hawk, M.D., M.P.H., the vice president of Cancer Prevention and Population Sciences and executive director of the Duncan Family Institute for Cancer Prevention and Risk Assessment.
“We want to know if we can prevent second primary cancers if we identify and treat HCV early enough,” Dr. Torres said. “And we have some preliminary data to support that HCV-associated second primary cancers are common and lethal in cancer survivors.”
HCV testing and treatment in cancer patients will become even more important if other cancers that have been anecdotally linked to HCV—such as cancers of the digestive tract, thyroid, kidney, prostate, lung, and nonepithelial skin—have their associations with the virus confirmed by studies similar to Dr. Torres’s. He said, “I expect that we’ll add more cancers to the list of malignancies associated with HCV.”
For more information, contact Dr. Harrys Torres at 713-792-6503 or firstname.lastname@example.org.
Economides MP, Amit M, Mahale PS, et al. Impact of chronic hepatitis C virus infection on the survival of patients with oropharyngeal cancer. Cancer. 2017. doi: 10.1002/cncr.31146. [Epub ahead of print]
Mahale P, Sturgis EM, Tweardy DJ, et al. Association between hepatitis C virus and head and neck cancers. J Natl Cancer Inst. 2016;108:djw035.
OncoLog, March 2018, Volume 63, Issue 3