There is not enough evidence to recommend for or against screening for oral
cancer, a government-backed panel said, due to a lack of data on possible
benefits and harms tied to screening.
The most common causes of oral cancer are cigarette smoking and alcohol as
well as the sexually-transmitted human papillomavirus, or HPV.
The American Cancer Society estimates 36 000 people will be diagnosed with
oral cancer in 2013 and close to 7 000 will die of the disease.
Evidence is lacking on whether screening can accurately detect oral cancer
and if earlier treatment of cancers found during those tests improves long-term
health, the US Preventive Services Task Force (USPSTF) found.
"It's not that oral cancer screening has been shown to be ineffective or too
risky or that it's been shown to be effective. The huge problem is a lack of
studies," said Dr Maura Gillison, who researches head and neck cancers at The
Ohio State University in Columbus.
Researchers found just one study of the effect of oral cancer screening on
deaths from cancer, an Indian trial that tracked 192 000 people over nine
That study did not show screening saved lives overall, but a second look
suggested smokers and alcohol drinkers benefited from the cancer checks.
Seven other studies that looked specifically at detection of oral cancer
during screening found a wide range of accuracy rates in healthcare workers'
positive and negative diagnoses.
Those studies were largely conducted in places with more oral cancers than
the US, such as India and Taiwan, the Task Force noted.
None of the trials estimated how many people suffer screening-related harms,
such as from further tests and treatments tied to false-positives.
'Alert care providers'
The new recommendations, currently in draft form, will be available for
public comment through here: Gillison, who is not part of the USPSTF, said it's
still a good idea for doctors and dentists to know the early signs of oral
cancer, including red or white patches, ulcerations or a mass in the mouth or
swelling of the lymph nodes.
Researchers "are trying to alert primary care providers to the signs of a
cancer, so that there isn't a delay in appropriate diagnosis and treatment,"
"We are all in favour of increased knowledge, increased awareness."
"This is not a recommendation about what to do if you have a symptom," agreed
Dr Albert Siu, co-vice chair of the USPSTF from the Mount Sinai School of
Medicine in New York.
"If you find something in your mouth, if you're concerned about something in
your mouth, by all means bring it to the attention of your doctor or your
dentist," he said.
For people without symptoms, he said, the lack of evidence one way or another
makes screening an individual call.
"If you have risk factors - heavy smoking, heavy alcohol use - it's something
to discuss with your doctor in terms of if it's worth looking in your mouth to
check," Siu said.
"I think that's something that would be reasonable."