SLC5A5 is not only well known for its association with CHT but is also well known as a gene that can predict the possibility of cancer based on a blood test before thyroid cancer surgery.[30,31] In particular, SLC5A5 has a high correlation with thyroid follicular adenoma but not with carcinoma.[31] Early diagnosis is crucial because endocrine tumors are often diagnosed as carcinomas based on the extent of invasion into the surrounding tissues rather than the direct presence of malignant cells. This evidence concerns the gene SLC5A5 and follicular thyroid adenoma.