Researchers at the University of Texas at Austin and Baylor College of Medicine have developed a new preoperative test for thyroid cancer that is faster and about two-thirds more accurate than the diagnostics physicians use today.1 Although more validation will be necessary before it can be used clinically, the new metabolic thyroid test shows promise for preventing thousands of unnecessary thyroid removals each year.
“If we could prevent people from having surgery they don’t need and enable them to have a more precise diagnosis, we can improve treatment for patients and lower costs for the healthcare system,” says Livia S. Eberlin, PhD, assistant professor of chemistry and diagnostic medicine at the University of Texas at Austin and coprincipal investigator.
Rachel DeHoog, a graduate student who worked on the study, adds, “Also very importantly, the ability to have certainty in your diagnosis is transformative for a patient presented with the grueling possibility of having cancer.”
Livia S. Eberlin, PhD, University of Texas at Austin. Photo courtesy of the Moore Foundation.
About 52,000 new cases of thyroid cancer are diagnosed each year in the United States.2 Unfortunately, the test used for diagnosis, called fine-needle aspiration (FNA), is inconclusive about one out of every five times. When a pathologist is unable to confirm the presence of cancer, the patient may receive a follow-up genetic test that can itself produce false-positive results.
Given such diagnostic uncertainties, doctors often recommend removing all or part of the thyroid—the gland in the neck that produces hormones that control the body’s metabolic rate as well as heart and digestive functions, muscle control, brain development, mood, and bone maintenance. Thousands of patients have the surgery each year, only to learn later that it was unnecessary.
A microphotograph of thyroid cancer cells, specifically papillary thyroid carcinoma. Photo courtesy Wendong Yu, MD, PhD, Baylor College of Medicine.
Using a technology called mass spectrometry imaging, the new metabolic thyroid test identifies metabolites produced by cancerous cells that act as a kind of diagnostic fingerprint. The researchers worked on identifying such diagnostic metabolic fingerprints for more than 2 years, using tissue specimens from 178 patients, before starting a pilot clinical study. During the clinical study, 68 new patients were tested, nearly a third of whom had received inconclusive FNA results. The new metabolic thyroid test returned a false positive only about one time in 10, and could have prevented 17 of the study patients from undergoing unnecessary surgeries.
The improved accuracy of the new test may prevent unnecessary surgeries, many of which lead patients to need hormone replacement therapy for the rest of their lives or to have to cope with other consequences of having all or part of their thyroid removed.
Amanda Helms, a graduate student in chemistry at the University of Texas at Austin, learned a few years ago that lumps on her thyroid were indicative of possible cancer. When her FNA biopsy came back as inconclusive, a doctor recommended removing the right half of her thyroid. A difficult surgery and recovery followed, though Helms soon received word that pathologists detected no cancer in the removed tissue. “All the uncertainty was nerve wracking,” says Helms, who adds that the new test could prevent others from going through what she did.
The thyroid is a gland in the neck that produces hormones that control the body’s metabolic rate, as well as heart and digestive function, muscle control, brain development, mood, and bone maintenance. Illustration by Melanie Connolly courtesy University of Texas at Austin.
“A lot fewer people would have to get surgery unnecessarily, which saves them time, money, and recovery,” Helms says. “It would also take away the uncertainty.”
James Suliburk, MD, a coprincipal investigator and head of endocrine surgery at Baylor College of Medicine, collected FNA biopsies from patients involved in the study and implemented the technology in a pilot trial to demonstrate the accuracy of the new test.
“With this next-generation test, we can provide thyroid cancer diagnoses faster and with more precision than current techniques,” says Suliburk. “This will be the new state of the art. We are able to do this analysis directly on the FNA sample and much more rapidly than the current process, which could take between 3 and 30 days.”
The team is now preparing to start a 2-year validation study, using FNAs from about a thousand new patients in Australia, Brazil, and the United States. If the results hold up, the researchers hope the technology will become a routine diagnostic tool.
For further information, visit the University of Texas at Austin.
References
- DeHoog RJ, Zhang J, Alore E, et al. Preoperative metabolic classification of thyroid nodules using mass spectrometry imaging of fine-needle aspiration biopsies. Proc Natl Acad Sci USA.2019;116(43):21401–21408.
- Key statistics for thyroid cancer [online]. Atlanta: American Cancer Society, 2019. Available at: www.cancer.org/cancer/thyroid-cancer/about/key-statistics.html. Accessed November 20, 2019.
Featured image:
A new preoperative test for thyroid cancer that’s faster and more accurate than the diagnostics that doctors use today could prevent thousands of unnecessary thyroid removals each year. Photo courtesy iStock.
