Establishment and clinical performance evaluation of the thyroglobulin colloidal gold immunochromatographic assay.

BACKGROUND: Lymph node metastasis increases recurrence risk in differentiated thyroid carcinoma (DTC). To address limitations of conventional detection, this study developed a novel quantitative diagnostic protocol to enhance preoperative assessment accuracy and guide optimal surgical management. METHODS: A total of 185 serum samples and 120 lymph node samples from patients scheduled for thyroid lateral neck lymph node resection or biopsy at the Head and Neck Surgery of Shaanxi Provincial Cancer Hospital between July 2023 and December 2023 were detected through the colloidal gold immunochromatographic assay (CGICA) and traditional Roche electrochemiluminescence immunoassay (ECLIA) methods, respectively. The paraffin pathology results served as the gold standard. RESULTS: The CGICA method demonstrated comparable performance to the Roche ECLIA method in serum sample detection, as evidenced by excellent correlation in regression analysis (r=0.996) and Bland-Altman agreement analysis. Notably, when applied to lymph node specimens, the CGICA method with a 22.05 μg/L cutoff value exhibited greater sensitivity than the Roche method with a 233.25 μg/L cutoff value (90% vs 86.25%). Importantly, the CGICA method achieved a diagnostic accuracy comparable to that of intraoperative frozen section histopathology while offering technical advantages in rapid thyroglobulin quantification via fine-needle aspiration biopsies. CONCLUSIONS: The current study demonstrates the potential of the CGICA method for thyroglobulin detection, which contributes to the rapid detection of cervical lymph node metastases in thyroid cancer patients (clinical trial registry number: ChiCTR2200063561).