University of Pittsburgh School of Medicine scientists and doctors are embarking on the first-ever clinical trial to determine whether a genetic test they pioneered could successfully spare patients with nonaggressive thyroid cancer from complete removal of their thyroid. Such thyroid-preserving surgery minimizes surgical complications, and many patients also may avoid taking medication every day to keep thyroid hormone levels in check.
Linwah Yip, MD
The 2-year trial, which is entirely philanthropically funded by individual donors affected by thyroid cancer, will investigate whether this molecular genetic test, ThyroSeq, can correctly differentiate between thyroid cancers most likely to spread and in need of complete removal of the thyroid gland and those likely to be far less invasive, warranting a thyroid-preserving surgical approach. “We’re looking at potentially saving patients from unnecessary surgery,” said Linwah Yip, MD, principal investigator of the trial.
“Today, we use the most recent developments in cancer genetics to guide treatment for many types of cancers such as breast and colon; we are hoping to safely apply the same approach to thyroid cancer. It’s exciting to be on the verge of tailoring the extent of thyroid surgery precisely to the aggressiveness of the cancer,” added Dr. Yip, Associate Professor of Surgery in Pitt’s Clinical and Translational Science Institute.
Under the current guidelines of the American Thyroid Association, when patients are diagnosed preoperatively with thyroid cancer, they can start by having just half of their thyroid removed. Often, this allows the remaining part of the thyroid to continue functioning naturally without long-term medication. However, a second thyroid operation can then be required if the removed cancer is an aggressive type. Alternatively, under the current guidelines, patients can skip the initial removal of half the thyroid and proceed straight to full removal of the thyroid—but they will definitely need medication for the rest of their lives.
Sally E. Carty, MD
“When we get a biopsy result that is positive for cancer before surgery, there are not a lot of tools that we can use to decide with patients which surgery is best,” said Sally E. Carty, MD, Professor of Surgery and Co-Director of the University of Pittsburgh Medical Center/University of Pittsburgh Cancer Institute Multidisciplinary Thyroid Center. “It becomes an educated guess that also is informed by the patient’s preference either to perform a partial removal of the gland and accept a potential repeat surgery if the cancer is found to be aggressive or to remove the entire thyroid in the initial surgery.”
ThyroSeq is a genetic test developed by a scientific team lead by Yuri Nikiforov, MD, PhD, Director of University of Pittsburgh Medical Center’s Division of Molecular and Genomic Pathology and Co-Director of the Multidisciplinary Thyroid Center. This latest version allows pathologists to simultaneously test 14 genes for 42 markers of thyroid cancer using just a few cells collected during the initial biopsy. The test has performed well at differentiating between cancerous and noncancerous thyroid nodules, already sparing patients from unnecessary surgeries.
Future Clinical Trials
Over the next 2 years, Dr. Yip and her colleagues plan to enroll about 100 patients with newly diagnosed thyroid cancer. Each participant’s biopsy sample will be tested with ThyroSeq to determine whether the cancer has an aggressive or nonaggressive genetic signature. The patients and their doctors can then use that knowledge to decide whether to remove half or all of the thyroid.
In addition, the clinical trial also will evaluate the quality-of-life parameters associated with complete removal of the thyroid gland. “I’m particularly passionate about this part of the trial,” said Dr. Yip, “because it will help us to know whether all of our efforts to preserve the thyroid are worth it.”
The trial can be found on ClinicalTrials.gov with the identifier NCT02947035. ■