Radiofrequency Ablation for Curative Treatment of Small Low-Risk Papillary Thyroid Cancer: Pilot Study

This pilot, single-arm clinical study evaluates the feasibility, safety, and effectiveness of radiofrequency ablation (RFA) as a curative treatment for small, low-risk papillary thyroid cancer (PTC). The study will enroll 30 adult patients (≥18 years) with biopsy-confirmed PTC measuring \<2 cm, who decline surgery or active surveillance, or who are transitioning from active surveillance to active treatment. Eligible participants will undergo ultrasound-guided RFA performed with curative intent at University Health Network. Patients will be followed for up to 12 months with scheduled clinical visits, neck ultrasounds, blood tests, voice assessments, and patient-reported outcome questionnaires. A biopsy of the ablation site at 6-12 months will be used to assess local cancer control. The primary objective is to determine the local cure rate and safety profile of RFA for low-risk PTC. Secondary objectives include evaluating post-ablation ultrasound features, patient-reported quality of life, and the feasibility of implementing a multidisciplinary thyroid RFA program within routine clinical practice. Results from this study will provide important preliminary data to inform future larger trials comparing RFA with surgery and active surveillance for selected patients with low-risk papillary thyroid cancer.

This study is a pilot clinical trial designed to evaluate a less invasive treatment option for adults with small, low-risk papillary thyroid cancer (PTC). PTC is the most common type of thyroid cancer and is often slow growing with an excellent prognosis. Standard treatment usually involves surgery to remove part or all of the thyroid gland. While surgery is highly effective, it may be associated with complications such as voice changes, low calcium levels, prolonged recovery, and the need for lifelong thyroid hormone replacement. For some patients, close monitoring without treatment (active surveillance) is an option, but this approach can cause ongoing anxiety and uncertainty. Radiofrequency ablation (RFA) is a minimally invasive, image-guided procedure that uses controlled heat to destroy targeted tissue. RFA has been widely used to treat benign thyroid nodules and is increasingly being explored as a treatment for carefully selected small thyroid cancers. This study aims to determine whether RFA can safely and effectively eliminate small PTCs while preserving the thyroid gland and reducing the impact of treatment on patients' daily lives. The study will enroll 30 adult participants (18 years or older) with biopsy-confirmed papillary thyroid cancer measuring less than 2 cm, with no evidence of spread outside the thyroid or to lymph nodes. All participants will have previously been offered standard treatment options and have chosen not to undergo surgery or active surveillance, or will be transitioning from active surveillance to active treatment. Each potential participant will be reviewed by a multidisciplinary team that includes radiology, endocrinology, and surgical specialists to ensure the treatment is appropriate and safe. The RFA procedure will be performed on an outpatient basis under local anesthesia and light sedation, using real-time ultrasound guidance to precisely target the cancer while protecting nearby structures such as the vocal cords, trachea, and esophagus. Patients are typically observed briefly after the procedure and can return home the same day. Following treatment, participants will be followed closely for up to 12 months. Follow-up includes clinic visits, neck ultrasound examinations, blood tests to assess thyroid function, voice assessments, and questionnaires that evaluate symptoms, quality of life, satisfaction with treatment, and decision-related concerns. A key component of follow-up is an ultrasound-guided biopsy of the treated area performed 6 to 12 months after RFA, which will be used to determine whether the cancer has been successfully eradicated. The primary focus of the study is to assess local cancer control and safety of RFA, including the frequency and severity of any complications. Additional goals include understanding how treated thyroid cancers appear on ultrasound over time, evaluating patient-reported outcomes, and assessing the practicality of delivering and sustaining a multidisciplinary thyroid RFA program within a Canadian academic health-care setting. The results of this study will provide important early evidence on the role of radiofrequency ablation as a potential alternative to surgery for selected patients with low-risk papillary thyroid cancer and will help guide future larger clinical trials and treatment guidelines.