The human papillomavirus (HPV) has long been linked to cervical cancer. With the recent launch of the FDA-approved Gardasil vaccine against four common strains of the virus, the spread of HPV infections can be slowed, cutting the risk of cervical cancer for many women for the first time.
But in an unexpected twist, researchers led by Carole Fakhry from the Sidney Kimmel Comprehensive Cancer Center at Hopkins have shown that infection with HPV actual improves a patient's chance of survival if they have head and neck cancer.
Head and neck squamous cell carcinoma (HNSCC) is the most common type of head and neck cancer. It can involve multiple tumors in the nose, sinuses, mouth and throat.
Previous literature recognizes the role of HPV in these tumors, noting that HPV-positive tumors in the head and neck have different characteristics, both clinical and molecular.
Of the different types of HPV, three strains in particular are thought to be highly transmissible and related to the formation of precancerous damage in hosts.
Fakhry and her team examined the differences in treatment between patients with HPV-positive and HPV-negative tumors.
Surprisingly, they found that when the HPV viruses were present in HNSCC tumor cells, patients actually responded better to chemotherapy and radiation.
A pool of 101 patients was studied. Laboratory analyses confirmed the presence of HPV virus in the tumor cells by measuring the cells' DNA. Long-term outcomes for the patients - the success of their treatment - was studied by following up on patients for three years after treatment.
The overall survival for patients with HPV-positive tumors was statistically higher than those with HPV-negative tumors.
Researchers estimated the effectiveness of treatment by looking at survival rates, or the number of patients who are still alive one year and two years after treatment.
For HPV-positive patients, the survival rate were as high as 97 percent for the first year after treatment and 95 percent for the second - close to a perfect cure rate.
For HPV-negative patients, however, the survival rate was 90 percent for the first year and dropped to 62 percent in the second.
Further analysis showed that patients with HPV-positive tumors had a 64 percent lower chance of dying than patients with HPV-negative tumors.
All told, about 40 percent of patients had HPV-positive tumors.
The results of this study indicate that the presence of HPV in HNSCC tumor cells might actually have a protective effect that has not been studied or characterized until now.
In the short term, these results should be considered for head and neck cancer patients with HPV-positive tumors.
Routine testing for HPV in head and neck cancers could offer a brighter outlook for patients.
