This study evaluates a thyroid-function-preserving alternative to routine total thyroidectomy for bilateral papillary thyroid carcinoma (PTC). Eligible adults undergo remote-access gas-less axillo-breast endoscopic hemithyroidectomy with level VI dissection on the dominant side, followed by ultrasound-guided radiofrequency ablation (RFA) of a ≤7 mm contralateral focus during the same anesthesia. Outcomes include structural-recurrence-free survival, endocrine-function preservation, safety, and quality of life over 24 months.

Bilateral PTC traditionally prompts total thyroidectomy, exposing patients to lifelong thyroxine replacement and a 1 - 3 % risk of permanent hypocalcemia. Building on a pilot cohort of 11 patients treated from June 2018 to September 2024 that showed no structural recurrence, no permanent RLN palsy, and preserved endocrine function after a median 17-month follow-updraft_Proof_hi, we launch a multicenter registry to confirm oncologic adequacy and functional benefits. Intervention: endoscopic hemithyroidectomy (dominant lobe) via gas-less axillo-breast approach plus central-neck dissection; then contralateral lesion RFA with a 17-gauge 0.7-cm active-tip electrode at 40 W (moving-shot). Follow-up at 1, 6, 12, 18, and 24 months includes ultrasound, serum Tg, calcium, PTH, and QoL instruments. Long-term surveillance continues annually to five years.

Inclusion Criteria:

• Age 18-65 years.
• Dominant-side PTC ≤1.5 cm suitable for endoscopic resection.
• Contralateral nodule ≤7 mm located ≥2 mm from posterior capsule.
• No radiologic lymph-node metastasis on contralateral side.
• Written informed consent.

Exclusion Criteria:

• Extrathyroidal extension, gross nodal or distant metastasis.
• Prior neck surgery, prior RFA/ethanol injection, or neck irradiation.
• Pregnancy or lactation.
• Serious comorbidities precluding anesthesia or follow-up.