In the stratified survival analyses, the expression of CD15 was also a predictor for the increased recurrence-free survival in subgroups of PTC patients with extrathyroidal extension (n = 357, p = 0.005) and lymph node metastasis (n = 306, p = 0.023) (Figure 2). This evidence concerns the gene FUT4 and metastatic malignant neoplasm in the lymph nodes.