Head and neck cancers include tumors of the mouth, throat, larynx, nasal cavity, salivary glands, and elsewhere. Tobacco use, alcohol use, and human papillomavirus (HPV) infection are important risk factors for these cancers. An estimated 55,000 people developed head and neck cancers in the United States in 2014. About 12,000 Americans die from the diseases each year. A better understanding of the causes behind these diseases can help lead to the development of new treatment approaches.
Most head and neck cancers—about 90%—are squamous cell carcinomas, which occur in the surface layers of cells in the body. Investigators with The Cancer Genome Atlas (TCGA) Research Network generated and analyzed genomic data on 279 head and neck squamous cell carcinomas from untreated patients. About 80% of the samples were from people who smoked. The majority were oral cavity cancers (61%) and larynx cancers (26%). TCGA is jointly supported and managed by NIH’s National Cancer Institute (NCI) and National Human Genome Research Institute (NHGRI). The study appeared on January 29, 2015, in Nature.
The TCGA team found that many HPV-associated tumors have specific genomic alterations, some of which are also found among a much broader set of mutations in smoking-related tumors. HPV is the most common sexually transmitted virus nationwide, and about 25% of head and neck cancers are linked to HPV infection. The HPV vaccines approved by the U.S. Food and Drug Administration can likely help prevent many cancers caused by HPV infection.
The researchers uncovered novel smoking-related cancer subtypes and potential new drug targets. In addition, they found numerous genomic similarities with other cancer types, including squamous cell lung and cervical cancers. These findings suggest possible common paths of cancer development and potential treatment opportunities.
Taken together, the results yield insights into how HPV infection and smoking affect head and neck cancer risk and disease development. They also suggest potential new diagnostic and treatment directions.
“The rapid increase in HPV-related head and neck cancers, noticeably in oropharyngeal tumors, has created an even greater sense of urgency in the field,” says lead author Dr. D. Neil Hayes at the University of North Carolina Lineberger Cancer Center at Chapel Hill. “We’re uncovering differences between tumors with and without HPV infection, and these new data are allowing us to rethink how we approach head and neck cancers.”
“While many head and neck cancers are preventable, they are increasingly common throughout the world, and often challenging to effectively treat over the long term,” says NCI Director Dr. Harold Varmus. “This type of broad analysis provides important new clues for future research and treatment directions.”
Source: National Institutes of Health