Further studies on larger PTC patients and PTMC with EI and/or LNM and/or positive BRAF V600E mutation patients (high risk PTMC patients) showed that there were no significant differences between these two patient groups in gender, age distribution, multifocal tumors, extrathyroidal invasion, Hashimoto's disease, lymph node metastasis, tumor TNM stages, PEDF positive expression, and the rate of recurrent disease. This evidence concerns the gene SERPINF1 and metastatic malignant neoplasm in the lymph nodes.