Papillary thyroid cancer does not necessarily break through the peritoneum in order to metastasize, and some patients with intact peritoneum may also have metastasis, only the probability of metastasis is relatively small. Papillary thyroid cancer is a kind of malignant tumor occurring in the thyroid gland, most patients have no obvious symptoms in the early stage, but with the development of the disease, symptoms such as discomfort in swallowing and difficulty in breathing may appear. Whether papillary thyroid cancer metastasizes or not is difficult to judge from the envelope, and some patients with intact envelope may also have metastasis of cancer cells. Usually, papillary thyroid cancer will not metastasize in the early stage of the disease, and the probability of metastasis is higher in the middle and late stages. Patients can judge the metastasis of papillary thyroid cancer through ultrasound, CT, X-ray and other examinations. It is suggested that patients should consult doctor for examination in time, and according to their conditions, they should be treated by surgery, radiotherapy and chemotherapy, so as to avoid delaying their conditions.