The competition for top genetic test for indeterminate thyroid nodules continues at this year's American Thyroid Association meeting.
Asuragen and Veracyte, and their respective rule-in versus rule-out tests, will now have to compete with version 2.0 of the IonTorrent-based assay from Yuri Nikiforov, MD, PhD, of the University of Pittsburgh Medical Center. The latter screens for nearly 60 genes and gene expression patterns, according to ATA scientific program co-chair R. Michael Tuttle, MD, of Memorial Sloan Kettering Cancer Center in New York City.
Like Asuragen's rule-in miRInform test (the test is now owned by Interpace Diagnostics), Nikiforov's ThyroSeq v2.0 panel attempts to pick out malignant nodules (the goal of Veracyte's Afirma test is to rule out cancer).
Nikiforov and colleagues will present their data during an oral session late Friday afternoon. The test is commercially available, as the researchers recently entered into a partnership with CBLPath laboratory.
"It's going to have to be validated," Tuttle said, "but it's a really strong runner as the test of the future."
ATA president Hossein Gharib, MD, of the Mayo Clinic in Rochester, Minn., said use of the Asuragen and Veracyte tests has spread more widely than seen at last year's ATA meeting, but clinicians are still determining how best to use them.
"Both are being used cautiously in practice," Gharib told MedPage Today. "We still need more data."
However, new draft guidelines that will be discussed at the meeting may influence which tests get further taken up into practice. New thyroid nodule guidelines will refrain from recommending a specific test since the field changes so fast, Tuttle explained. But the guidance will be decisive regarding certain test characteristics.
"We're not saying which one to use. We're going to set the bar and say, 'you need a negative predictive value [NPV] of 95%,'" Tuttle said. "Whoever can come up to that bar, we will accept their test."
The Veracyte test has indeed met the bar of a 95% NPV, and the ThyroSeq panel has an NPV of 96%, according to the meeting abstract.
Other draft guidelines slated to be discussed at the meeting include thyroid cancer, medullary thyroid cancer, and hypothyroidism, Gharib said.
Tuttle said new research from Mingzhao Xing, MD, of Johns Hopkins, and colleagues, will go "beyond the nodule story" into helping better determine the prognosis for malignant thyroid tumors.
In a late-breaking abstract presentation on Saturday morning, Xing and colleagues will present data on screening for the combination of an established thyroid cancer gene BRAF and telomerase reverse transcriptase (TERT), another driver of tumorigenesis.
Thyroid cancers with the combination of the BRAF V600E and TERT mutations drive an extremely aggressive form of thyroid cancer, Tuttle said.
"Clinically, we think of molecular biology as helping us determine, is it cancer -- yes or no?" Tuttle said. "But now we're starting to understand what it means if it is cancer and it has [these mutations]. If you know that a tumor has the rare combination of both mutations, it's a bad prognostic sign."
Making a Thyroid From Scratch?
It's a thyroidologist's dream to be able to replace a thyroid that's been surgically removed with a brand new thyroid, and early work presented at an oral session on Thursday morning may help move the needle on that goal.
Terry Davies, MD, of Mount Sinai Hospital in New York City, and colleagues, will present new strategies for inducing human embryonic stem cells into thyroid cells.
Although the work is still in very early stages, Tuttle said it would be "wonderful to be able to regrow a normal thyroid" if the original had to be removed.
TSH Suppression: Who's a Candidate?
There's been debate about the extent of thyroid-stimulation hormone (TSH) suppression following treatment for differentiated thyroid cancer.
"We're doing less intense therapy these days," Tuttle said. "We used to keep TSH suppressed forever, but we saw some complications, including osteoporosis and atrial fibrillation."
Aubrey Carhill, MD, in collaboration withSteven Sherman, MD, of MD Anderson Cancer Center in Houston, will present data during an oral session on Thursday on long-term outcomes with TSH suppression in this population.
"This research will help us understand which patients need that suppression, and which patients you can do less to," Tuttle said.
Thyroid Tx During Pregnancy
Methimazole (Tapazole), the drug of choice for Graves' disease, has been linked to birth defects, and clinicians have to switch their pregnant patients to propylthiouracil (PTU).
Japanese researchers will present data from a prospective, multicenter observational study on methimazole embryopathy during the first 12 weeks of pregnancy.
Their data will be an interim report following the fifth case of methimazole-related anomalies, which occurred in 2011. In the abstract, they recommend "avoiding continuation of [methimazole] during the organogenesis period in women with Graves' disease.
"We love methimazole," Tuttle said, "but if the patient is pregnant, you have to use PTU."
Disclosures
Tuttle reported relevant relationships with Veracyte.