A novel test that looks for a molecular
fingerprint in needle biopsies could help
improve the diagnosis of thyroid cancer
and reduce unnecessary surgeries,
according to new research.

A new thyroid cancer test could prevent unnecessary
invasive procedures.
A recent PNAS paper describes the new test and
how it performed in a pilot study.

The findings showed the new method to be faster
and around two-thirds more accurate than those that
doctors currently rely on to diagnose thyroid cancer.
The researchers say that larger trials now need to
validate these early findings before doctors can start
using the new test as part of routine clinical
diagnosis of thyroid cancer.

Should the larger studies confirm the findings, the
new test could prevent thousands of unnecessary
partial or total thyroid removals each year in the
United States.

Many patients who undergo thyroid removal have to
take hormone replacement therapy for the rest of
their lives.

"If we could prevent people from having surgery they
don't need and enable them to have a more precise
diagnosis," says co-senior study author Livia S.

Eberlin, Ph.D., assistant professor of chemistry and
diagnostic medicine at The University of Texas at
Austin, "we can improve treatment for patients and
lower costs for the healthcare system."

Thyroid cancer diagnoses
have gone up
The thyroid is a butterfly-shaped gland in the base
of the throat under the Adam's apple, or thyroid
cartilage. The gland has an important role in the
endocrine system.

With the help of iodine, the thyroid gland releases
hormones that control metabolic rate, heart rate,
body temperature, and blood pressure .

Since 1992, annual rates of thyroid cancer
diagnoses in the U.S. have climbed from 6 to more
than 14 per 100,000 adults, according to the
Surveillance, Epidemiology, and End Results (SEER)
Program of the National Cancer Institute (NCI), one
of the National Institutes of Health (NIH).

The NCI's SEER program also estimate that there
were 822,242 people living with thyroid cancer in
the U.S. in 2016.

The American Cancer Society suggest that the main
reason for the dramatic rise in thyroid cancer
diagnoses in recent decades is the greater use of
diagnostic technology such as ultrasound that can
spot small nodules in the thyroid.

Limitations of current
thyroid biopsy method
To diagnose thyroid cancer, doctors usually begin
with a biopsy procedure called fine needle
aspiration (FNA) to remove some thyroid tissue. A
pathologist then examines the biopsy samples to
see if the tissue is cancerous.

However, because of the limitations of the current
tissue analysis tools, around 1 in 5 FNA tests
cannot confirm whether cancer is present or not.

When FNA tests are inconclusive, doctors may then
carry out genetic tests, but even these can return
false-positive results: that is, indicate that thyroid
cancer is present when it isn't.

Because of these uncertainties, doctors often
suggest that patients undergo partial or total
removal of the thyroid.

The team behind the current study used mass
spectrometry imaging to develop a molecular
profile, or fingerprint, of the cancer. This technology
allows scientists to identify the chemical
byproducts, or metabolites, of cancer cell activity.

To find out which particular metabolites to include
in the fingerprint, the team compared molecular
profiles from tissues of 178 people with or without
thyroid cancer.
Faster and more accurate
FNA tests
The researchers then tested the accuracy of the new
fingerprint model in a pilot trial involving 68 people
who underwent FNA tests. Nearly a third of these
people had received inconclusive FNA results.

The findings revealed that the new fingerprint test
produced false-positive results in around 1 in 10
cases only. A test with this level of accuracy could
have kept 17 study participants from undergoing
unnecessary surgery.

The team is already preparing a 2-year trial to
validate the FNA findings of roughly 1,000 people
in Australia, Brazil, and the U.S.

"With this next generation test," says co-senior
study author Dr. James W. Suliburk, associate
professor and chief of endocrine surgery at Baylor
College of Medicine, in Houston, TX, "we can
provide thyroid cancer diagnoses faster and with
more precision than current techniques — this will
be the new state-of-the-art."