Publicly Funded Molecular Testing of Indeterminate Thyroid Nodules: Canada's Experience.

Abstract

Indeterminate thyroid nodules (ITNs) lead to diagnostic surgeries in many countries. The use of molecular testing (MT) is endorsed by several guidelines, but costs are limitative, especially in public health care systems like in Canada. The primary objective of this work was to evaluate the clinical value of ThyroSeq v3 (TSv3) using benign call rate (BCR) in a real-world practice. The secondary objective was to assess the cost-effectiveness of MT. This multicentric prospective study was conducted in 5 academic centers in Quebec, Canada. A total of 500 consecutive patients with Bethesda III (on 2 consecutive cytopathologies) or IV and TIRADS 3 or 4 nodules measuring 1 to 4 cm were included. MT was performed between November 2021 and November 2022. Patients with a positive TSv3 were referred for surgery. Patients with a negative TSv3 were planned for follow-up by ultrasonography for a minimum of 2 years. The BCR, corresponding to the proportion of ITNs with negative TSv3 results, was assessed. A total of 500 patients underwent TSv3 testing, with a BCR of 72.6% (95% CI, 68.5%-76.5%; P < .001). Ultimately, 99.7% of patients with a negative result avoided surgery. The positive predictive value of TSv3 was 68.2% (95% CI, 58.5%-76.9%). The cost-benefit analysis identified that the implementation of MT would yield a cost savings of $6.1 million over the next 10 years. The use of MT (TSv3) in a well-selected population with ITNs led to a BCR of 72.6%. It is cost-effective and prevents unnecessary surgeries in a public health care setting.