The core of standardized treatment of thyroid cancer is standardized surgical approach. According to international and domestic standards, for differentiated thyroid cancer, there are only two types of thyroidectomy: total thyroidectomy and unilateral lobectomy and isthmus. For medullary carcinoma and undifferentiated carcinoma, total thyroidectomy is more often used. Therefore, total thyroidectomy is the basic surgical procedure for thyroid cancer. In some cases, a very small amount of the non-tumor side of the gland is preserved in order to better protect the function of the laryngeal recurrent nerve and parathyroid glands, which is called subtotal thyroidectomy. For differentiated nail cancer, unilateral lobectomy and isthmus are also commonly used because of the slow progression and good prognosis in most cases, but the following indications must be strictly followed: tumor ≤ 25px; single cancerous foci; no invasion of the thyroid peritoneum; no clear metastasis in lymph nodes; no nodules in the contralateral lobe; non-high risk type; no family history of nail cancer and childhood radiation history. The above points must be met before unilateral lobectomy and isthmus can be chosen. In the latest ATA guidelines, the tumor size has been relaxed to 1~100px. It seems that unilateral resection will be used in more and more cases, but it is not. It is difficult to be accurate in certain criteria preoperatively. For example, whether the tumor is a solitary lesion is difficult to detect for <2.5px< span=""> cancer foci either by preoperative ultrasonography, intraoperative exploration and frozen pathology. Another example is whether there are metastases in lymph nodes. Even if no obvious abnormal lymph nodes are seen intraoperatively and the frozen pathology examination is negative, micro-metastatic lesions can still be found in postoperative pathological sections. Another example is whether the tumor is a high-risk type, which is also determined only after postoperative pathological examination, after special staining and genetic screening. And there is no obvious linear relationship between these factors and the size of the tumor. Therefore, when choosing unilateral lobectomy and isthmus resection for differentiated nail cancer, one still faces some less than ideal situations: for example, preoperative evaluation of single cancer foci postoperative pathology reports multiple cancer foci, preoperative belief of no lymph node metastasis postoperative pathology reports more lymph node metastasis. Moreover, unilateral resection has the disadvantages of not being able to be followed up with thyroglobulin antigen (Tg) and not being able to receive radioiodine therapy, and some patients have undergone reoperation to remove the contralateral glandular lobe during the follow-up process. In conclusion, careful evaluation and selection should be made when considering unilateral lobectomy and isthmus for the treatment of nail cancer, and further studies by specialized physicians are needed.