A new blood
test developed by University of North Carolina Lineberger Comprehensive Cancer
Center researchers shows promise for tracking HPV-linked
head and neck cancer patients to ensure they remain cancer-free after treatment.
Researchers will present preliminary
findings at the 60th Annual Meeting of the American Society for Radiation
Oncology in San Antonio on Tuesday, Oct. 23. Their study evaluated a blood test
for HPV-linked oropharyngeal squamous cell carcinoma, which is a cancer of the
back of the throat. The findings demonstrated the test could be an effective
and less costly alternative for monitoring for cancer recurrence after
radiation treatment.
"The
goal of this study was to evaluate whether this test can be used to track
patients who are completely asymptomatic, and thought to have no active
cancer," said UNC Lineberger's Gaorav P. Gupta, MD, PhD, assistant
professor in the UNC School of Medicine Department of Radiation Oncology.
"We already knew that our test was very sensitive and specific, but we did
not know the degree to which it would be useful in early detection of disease
recurrence in patients who are otherwise thought to be disease-free."
HPV,
or the human
papillomavirus, is the most common cause of sexually transmitted infection
in the United States, according to the U.S. Centers for Disease Control and
Prevention. Infection with certain strains of HPV can cause cervical cancer in
women, genital cancers in both men and women, and cancer of the oropharynx,
which is the back of the throat, including the base of the tongue and tonsils.
The CDC estimates that approximately 70 percent of oropharyngeal
cancer cases diagnosed in the United States are probably caused by HPV,
which accounts for nearly 13,000 cases per year.
Gupta
and his colleagues developed a blood test that can detect fragments of HPV's
genetic material that have been released into the blood by dying cancer cells.
"We
realized it is important to distinguish HPV
DNA that's being released by dying tumor cells from the natural HPV DNA
that is present during a viral infection," Gupta said. "Our method
accomplishes this feat, thus making it a more sensitive and specific test for
cancer."
For
their study, the researchers followed 89 patients with HPV-associated
oropharyngeal squamous cell carcinoma who received chemotherapy and radiation
treatment. They administered the blood test before and during treatment, and
then during follow-up visits. The patients received scans three months after
treatment, and then came back for clinical exams every two to four months
during the first two years, and then every six months in years three through
five. Patients received X-rays or CT scans every six months, and again if they
had positive HPV results.
"We
are detecting subclinical disease with this blood
test, and the imaging patients received confirmed those findings,"
said UNC Lineberger's Bhishamjit S. Chera, MD, associate professor in the UNC
School of Medicine Department of Radiation Oncology and the study's
co-corresponding author. Chera presented the findings from the study at the
ASTRO meeting.
Of
the 70 patients whose blood tests were negative three months after treatment,
none developed recurrence. Nineteen patients had positive blood tests, and
eight of those patients developed recurrence. Physicians are continuing to
monitor the remaining eleven who had positive blood tests but no evidence of
recurrence.
"The
most striking finding of our study is that of the patients who did not have any
signal using our blood
test, none of them developed disease recurrence," Chera said.
"That raises the question: Do we need to be scanning these patients? Scans
come with a lot of cost, and because of the cost, we're not able to do it as
frequently. Patients end up having a lot of anxiety from one scan to the next,
wondering if their cancer has come back. This blood test could spare patients
the need for additional imaging and potentially alleviate some anxiety."
The
researchers say the next steps will involve investigating whether the test can
be used prospectively to monitor patients and to make decisions that could
avoid unnecessary imaging, thereby reducing costs. They also see additional
applications for the blood test, including monitoring for other HPV-linked
cancers, including cervical
cancer.
"We
are confident this blood test will be translatable to other cancers driven by
HPV, and as a monitoring tool for cancer diagnosis," Chera said. "We
strongly believe that this test may also have a role in screening, not just for
oropharyngeal cancer, but also cervical or anal
cancers, possibly in a general population setting, or at least in patients
who may be at higher risk of developing these conditions."
In
addition to Chera and Gupta, other authors include Sunil Kumar, PhD; Colette
Shen, MD, PhD; Robert Amdur, MD; Roi Dagan, MD; Jared Weiss, MD; Juneko
Grilley-Olson, MD; Adam Zanation, MD; Trevor Hackman, MD; Jeff Blumberg, MD;
Samip Patel, MD; Brian Thorp, MD; Mark Weissler, MD; Nathan Sheets, MD; and
William Mendenhall, MD.
The
study was supported by the University Cancer Research Fund, Burroughs Wellcome
Fund, the University of North Carolina School of Medicine Department of
Radiation Oncology, UNC Lineberger and the University of Florida School of
Medicine Department of Radiation Oncology.
Intellectual
property related to the test and held by the University of North Carolina at
Chapel Hill has been licensed to Naveris, a company in which Chera and Gupta
hold equity stakes.
Registration: https://std-hiv-aids.cmesociety.com/registration
Abstract Submission: https://std-hiv-aids.cmesociety.com/abstract-submission
