Abstract: The recent development and wide application of ultrasonography and ultrasonographyguided fine needle aspiration biopsy have greatly facilitated the detection of papillary thyroid microcarcinoma (PTMC). Currently, the occurrence, development and pathological features of PTMC are not clearly understood. Therefore, no consensus on the diagnosis and treatment has been reached. Patients with PTMC are suggested to be closely observed and periodically examined with ultrasonography in some countries such as Japan, and these patients are to be operated when the tumor enlarged or new lymphatic metastasis are found. Operation is the first choice in the European and American countries, and the longterm survival rates of these patients are nearly 100%. For the PTMC patients with the risk factors such as thyroid capsule invasion, lymphatic metastasis, multifocal lesion, higher degree of malignancy, thyroid stimulating hormone suppression therapy was given after operation, which may reduce the local recurrence rate. In China, we should hold well the "limitation" and choose the best way for different patients according to the personalized principle in clinical practice.

Key words: Thyroid neoplasms, Carcinoma, papillary, Observation, Surgical procedures, operative, Prognosis