The first symptom of papillary thyroid cancer is a painless lump in the neck, most of which moves up and down with swallowing, while a few have hoarseness, dysphagia and pressure. In recent years, there are few cases of thyroid cancer found accidentally during health check-ups. Diagnosis of papillary thyroid cancer 1. Ultrasonography is the imaging test of choice. The diagnostic accuracy of experienced ultrasonographers can reach over 85%. A thyroid swelling with unclear border, uneven internal echogenicity, rich blood flow and fine sand-like strong echogenicity often indicates thyroid cancer. If there are also enlarged lymph nodes in the neck with calcification or cystic changes, thyroid cancer is more likely. 2.CT or MRI can further understand the relationship between thyroid mass, enlarged lymph nodes and surrounding tissues such as trachea, esophagus, larynx and large blood vessels in the neck. This examination can be very helpful to surgeons in locally advanced cases. 3.Laryngoscopy To understand whether the vocal folds are moving normally to determine the involvement of the recurrent laryngeal nerve. 4.Cytological examination The diagnostic accuracy can reach more than 85%, and the diagnostic accuracy of metastatic lymph nodes in the neck is even higher. It is an invasive test and requires an experienced cytologist. Most of the primary hospitals in China cannot carry out it. 5.PET-CT is very helpful to determine whether thyroid cancer has metastasis in the lungs and bones of the whole body, but it is expensive and not a routine test. 6.Thyroid scan Thyroid nuclear scan often shows “cold nodules”, but the specificity is not high, so it is not recommended for routine examination.