New research shows that the Human Papillomavirus (HPV) may have a role to play in many more types of head and neck cancers than we think.

Published in the Journal of Clinical Oncology, the study by researchers from University College London and the University of Southampton looked into HPV’s role in tumor development to gauge the viability of different treatment options for patients suffering from specific types of cancer.

HPV — particularly infecting the skin and the moist membranes in some parts of the body — is known to cause certain types of cancers, most commonly cervical and tonsil (oropharyngeal). There is evidence that suggests that HPV associated (HPV+) oropharyngeal cancer is more easily detected by a patient’s immune cells (T-cells), allowing them to respond more readily to treatment, as compared to those with HPV- type of tumors.

The research team attempted to use this hypothesis on a small percentage of head and neck cancers at sites other than the tonsils to check whether a similar response can be observed. However, the chances of survival for the HPV+ cases did not improve in the other types of cancer.

“When we looked at HPV+ cancers at other head and neck sites, we didn’t see the same survival benefit or infiltration of T-cells as we did in the HPV+ tonsil cancers,” senior author Dr. Tim Fenton, senior research associate at UCL Cancer Institute explained in a press release. “And we think that this is the major difference in determining the difference in patient prognosis.”

He went on to explain that between HPV+ oropharyngeal cancer and HPV+ cancers in other areas of the head and neck, the difference in immune cell numbers may arise from the difference in the anatomy of the tonsils.

“The tonsils are composed of lymphoid tissue, so there are many immune cells already present in this area. There’s a possibility that cancers developing in the tonsils are very visible to the immune system in that respect,” Fenton said. “However, HPV- oropharyngeal cancers contain far fewer T-cells, so it appears to be a combination of having a virally driven cancer that is located in the tonsil that gives a strong immune response, and much better clinical outcome.”

Fenton also said that as there were HPV-targeted therapeutic vaccines undergoing clinical trials now, there was more scope for research in the links between the virus and cancer.

“Currently, we test oropharyngeal cancers for HPV, but not cancers arising at other sites in the head and neck,” he explained. “Even though numbers of these patients are relatively small - approximately 1 in 25 patients - they likely benefit from vaccination, particularly as these treatments become more fully developed, means that testing should be more widespread for these specific cancers."