April 14, 2008 (San Diego) -- Researchers have developed a DNA spit test to
detect the earliest signs of head and neck cancer, when it is more
curable, and they say it could be available by the end of the year.
Also in the works -- though not as far along -- is an oral swab test to
gauge whether someone is at increased risk of developing lung cancer.
If it pans out in future research, the swab test could also be used to
predict who has a high probability of developing head and neck cancer and other
tobacco-related cancers, the researchers say.
More than 40,000 Americans are diagnosed with head and neck cancer annually
and about 12,000 die of it. A total of 215,020 Americans will be diagnosed with
lung cancer in 2008, and it will kill 161,840, according to the American Cancer
Both new tests were discussed at the annual meeting of the American
Association for Cancer Research.
"Living Like Hell'
Seema Sethi, MD, tells WebMD that she "jumped into research to find a
test to pick up head and neck cancer earlier" after losing her dad to a
tobacco-related cancer. Sethi is a specialist in otolaryngology-head and neck
surgery at Henry Ford Hospital in Detroit.
"Everyone knows smoking and alcohol are
associated with head and neck cancer, but no one knows who's going to get
it," she says.
Currently, most cases are diagnosed in advanced stages, when prognosis is
poor, Sethi says. "Despite the best of treatments, outcomes are not as good
as if it was picked up earlier," she says.
Head and neck cancer is one of the most horrendous of diagnoses. "You
have to chop off part of the patient's face. They often can't swallow or eat
solid food. There's a lot of mouth odor. So even if you're living, you're
living like hell," Sethi says.
Gene Test Predicts Head and Neck Cancer
Because the development of the disease in people at high risk, such as
smokers, takes many years, Sethi reasoned that this "window" period
offered an opportunity for early screening.
She came up with the idea of looking for two genes -- PMAIP1 and PTPN1 --
that are associated with head and neck cancer. Abnormalities in either gene
signal the cancer.
The researchers took saliva samples from 27 patients with head and neck
cancer and 10 healthy people without cancer. "Patients just spit in a
cup," Sethi says.
The researchers extracted DNA from the samples and analyzed it.
"Lo and behold, we could completely separate out the cancer patients
from the normal non-cancer healthy people," she says.
Sethi says the next step will be to validate the test in people who come in
for head and neck screening because "they are a smoker, have a family
history, or other reasons. By the end of the year, we hope to have an early
test for head and neck cancer," she says.