EFNB2 overexpression is associated with poor outcome in thyroid cancer [58], glioblastoma [59], and cholangiocarcinoma [60], as well as pancreatic [61], bladder [62], ovarian [63], and endometrial carcinomas [64], whereas it is associated with a favorable prognosis in breast cancer [65]. This evidence concerns the gene EFNB2 and thyroid cancer.