Article ID: EJ12-0256
This study created a new staging system using a risk model that employed clinical factors that were associated with recurrence, verified by preoperative clinical information and intraoperative finding and was compared with other staging systems. A review was conducted of patients who have undergone thyroidectomy and followed-up between January 1, 1983 and September 31, 2007 at Yonsei University Wonju Christian Hospital. The final prognostic staging system was defined as University of Yonsei clinical staging system (Prognostic score = 0.03 × Age + 0.8 × (if male gender) + 0.5 × (if extrathyroidal tumor extension present) + 0.7 × (if clinically apparent lymph node metastasis present), Stage I, less than 1.50; Stage II, 1.50 to 2.29; Stage III, 2.30 to 3.29; Stage IV 4, 3.3 or more). Compared with the other staging systems, the proportion of variation explained (PVE %) was calculated for each. The University of Yonsei clinical staging system appeared to be first as an accurate prognosis predictor with 11.9%. New staging system can predict recurrence and has advantage can use preoperative clinical information and intraoperative finding. Those who are diagnosed as high risk patients using the new staging system should be treated with aggressive surgical treatment and close follow-up.