This research will evaluate the role of tissue proteome profile in regional metastatic disease. Considering that one of the main factors of survival in patients with papillary thyroid carcinoma is the presence of regional or distant metastatic disease, this research will focus on the difference in the proteome profiles between papillary thyroid carcinomas which had regional metastatic disease present at the time of surgery, and ones that did not have regional metastatic disease in neck lymph nodes at the time of surgery. In this study, 10 samples of papillary thyroid carcinomas without regional metastatic disease and 10 samples of well-differentiated papillary thyroid carcinomas with regional metastatic disease will be analyzed. The goal of this research is to try to identifiy certain differences in tissue proteomic profiles of papillary thyroid carcinoma depending on the presence of regional metastatic disease in neck lymph nodes.