Detection of papillary thyroid carcinoma with serum protein profile analysis

Objective: To determine the sensitivity and specificity of surface-enhanced laser desorption/ionization time-offlight mass spectrometry (SELDI-TOF-MS) for papillary thyroid carcinoma (PTC) detection. Design: The SELDI-TOF-MS protein profiles of patients with PTC, patients with benign nodular disease (BND), and healthy controls were analyzed to determine the sensitivity and specificity of SELDI-TOF-MS assay for PTC detection. Data analysis was performed to process the spectral data and classify the disease status of the patients. Setting: Academic tertiary care hospital. Patients: Serum samples were collected prospectively from 7 patients with PTC, 8 patients with BND, and 7 healthy control volunteers. Intervention: All patients diagnosed as having PTC or BND underwent thyroidectomy from October 21, 2004, to January 31, 2006. Main Outcome Measures: Twenty-two serum samples were analyzed. Results: Most protein peaks resolved by the SELDI-TOF-MS assay were in the range of 1 to 20 kDa. Classification tree analysis based on peak expression distinguished patients with PTC from those with BND with 85.7% sensitivity and 100% specificity. Serum samples from patients with PTC differed most significantly from those of patients with BND by the underexpression of a protein peak at 11 101 Da. Conclusions: This pilot study demonstrates that proteomic analysis of serum protein profiles distinguishes patients with PTC from patients with BND with a high degree of sensitivity and specificity. Further investigation into the clinical utility of this technology in PTC biomarker detection and surveillance is warranted.