New research helps shed light on precision detection of thyroid cancer

A new study involving U of T researchers has uncovered new insights into how thyroid cancer may be more effectively treated.

The research — recently published in JAMA Network — involved Guodong (David) Fu and Ronald Chazen of the Lunenfeld-Tanenbaum Research Institute and the Alex and Simona Shnaider Research Laboratory in Molecular Oncology at Mount Sinai Hospital, as well as Christina MacMillan, an assistant professor in the Temerty Faculty of Medicine’s department of laboratory medicine and pathobiology, and Ian Witterick, a professor in Temerty Medicine’s department of otolaryngology - head and neck surgery.

For the study, researchers looked at thyroid tumor tissues and thyroid nodule biopsies from 620 patients at Mount Sinai Hospital, from 2016 to 2022.

Researchers examined whether differences in the patients' RAS genomic variants were reflected in the status of their tumours. They also investigated the presence of the variant BRAF V600E, and TERT promoter variants, in the patient’s samples.

Ultimately, the researchers concluded that “discrimination of interpatient differences in RAS in combination with BRAF V600E and TERT promoter variants” could lead to more accurate cancer diagnosis, by doing molecular assays of cellular biopsies from patients with thyroid nodules.

“The findings help promote understanding of the interpatient differences in genomic variation among patients who carry the same genetic mutation, thereby facilitating individualized treatment based on the extent of the mutation present in the patient,” says Fu.

For the study, Fu says researchers developed novel molecular assays using digital polymerase chain reaction, a technique that means they could sensitively quantify the genetic mutation level of the patient materials.

The paper notes that there has been a sharp increase in papillary thyroid cancer since the 1980s, and that in 30 per cent of cases where a fine-needle aspiration biopsy of a suspected nodule takes place, there is an indeterminate diagnosis, which may lead to a diagnostic surgery.

Fu says research that assists with precision thyroid cancer detection is important for many reasons, including that some patients who seek treatment for thyroid tumours end up finding out their tumours are benign after diagnostic surgery. The findings could help medical practitioners differentiate low-risk tumours from high-risk ones, he says, and help avoid unneeded surgical procedures.

“(This finding) enhances the preoperative diagnostic accuracy for patients, in order to avoid unnecessary surgery for benign thyroid nodules,” says Fu.

Witterick, who is also surgeon-in-chief and otolaryngologist-in-chief at Mount Sinai Hospital, agrees and says the research is important because identifying differences in genomic variants between patients can enhance precision in cancer detection, especially diagnosing malignancies before surgery and distinguishing low-risk cancers from more aggressive ones.​