Differentiating Follicular Thyroid Carcinoma and Thyroid Adenoma by Using Near-Infrared Surface-Enhanced Raman Spectroscopy

We aimed to identify the differentially expressed molecules in the serum and neoplastic tissue of patients with follicular thyroid carcinoma (FTC) and thyroid adenoma (TA) by using near-infrared surface-enhanced Raman spectroscopy (NIR-SERS) and to further investigate the diagnostic efficiency in differentiating FTC and TA. Clinical samples of serum and neoplastic tissue of patients with FTC (n = 40) and TA (n = 40) were collected. NIR-SERS was performed to investigate the Raman spectra in these samples. Raman spectra in FTC group and TA group were compared to explore the difference. The characteristic Raman peaks of serum and neoplastic tissue of FTC and TA appeared in the wavelength range of 400 cm⁻¹ to 1800 cm⁻¹. The most different Raman peaks between FTC and TA tissues located in the wavelengths of 756 cm⁻¹, 1004 cm⁻¹, 1261 cm⁻¹, 1450 cm⁻¹, and 1660 cm⁻¹ (P < 0.001 for all). The Raman intensity of FTC tissue in 756 cm⁻¹ and 1004 cm⁻¹ was significantly weaker than that of TA tissue. Using two principal components of FTC and TA tissues could accurately differentiate the two diseases (accuracy = 100%). There was no significant difference between the Raman spectra of FTC serum and TA serum. NIR-SERS of thyroid tissue could accurately and quickly differentiate FTC and TA. NIR-SERS could be a novel modality for the diagnosis of thyroid tumors and requires further promotion in clinical investigations.