Using a new blood test that’s in development, University of North Carolina Lineberger Comprehensive Cancer Center researchers identified characteristics that could be used to personalize treatment for patients with a type of head and neck cancer linked to HPV infection.
Researchers believe the findings, published in the journal Clinical Cancer Research, could help identify those patients with characteristics linked to improved treatment responses. They hope to tailor therapy for those patients to reduce their exposure to potential toxic side effects.
“Head and neck cancers that are caused by HPV infection tend to have a better overall outcome than head and neck cancers related to other factors like smoking and alcohol,” said UNC Lineberger’s Gaorav Gupta, MD, PhD, assistant professor in the UNC School of Medicine Department of Radiation Oncology. “There’s been a lot of interest in exploring whether we can give less treatment to these patients and still achieve the same level of cure, while reducing the toxicities of treatment. The goal of this study was to investigate whether a blood test for circulating tumor HPV DNA can potentially be used to monitor the response of a patient’s cancer to chemotherapy and radiation.”
The researchers developed the test to detect levels of DNA in the blood from HPV-linked oropharyngeal squamous cell carcinoma tumors. Studies are ongoing to see if the test can be used to monitor patients’ response to treatment with radiation and chemotherapy.
In their latest work, researchers identified characteristics in patients that could be used to stratify and personalize treatment. They drew their findings from a study of the blood test results from 103 patients who were undergoing chemotherapy and radiation for HPV-linked oropharyngeal squamous cell carcinoma.
One characteristic that emerged from their study as a biomarker of a good outcome was a high level of circulating tumor HPV DNA in the blood before treatment. Since the finding seems counterintuitive, researchers plan to investigate why a high level of initial viral DNA in the blood would be linked to a better outcome.
In addition, they found that patients who then rapidly cleared the circulating tumor DNA from their blood were more likely to have improved outcomes. Patients who were able to clear more than 95 percent of the DNA from their blood by day 28 of treatment were considered to have a favorable clearance rate. For 19 out of 67 patients with those two favorable biomarkers, they found that none had persistent or recurrent disease.
Conversely, they found that cancers with low levels of circulating DNA from tumors at the outset—or less than 200 copies of HPV DNA per milliliter—and with unfavorable clearance of HPV DNA after treatment had a higher risk of recurrence. That risk was even worse when combined with other risk factors such as an extensive history of smoking.
