Low pathological differentiation of tumor generally refers to poorly differentiated carcinoma, and poorly differentiated carcinoma does not necessarily metastasize, and its metastasis is related to the stage of the disease, the degree of differentiation and the pathological type of the tumor. Poorly differentiated carcinoma generally refers to malignant tumors of epithelial tissue origin, including poorly differentiated adenocarcinoma, poorly differentiated squamous carcinoma, poorly differentiated small cell carcinoma and other types, which have higher degree of malignancy, faster development, higher probability of metastasis and recurrence, and generally poorer healing. Metastasis of poorly differentiated carcinoma is related to its stage, differentiation degree and pathological type. In terms of pathologic type, metastasis can occur at the early stage of the disease in patients with poorly differentiated carcinoma and small cell carcinoma, but the probability of metastasis in squamous carcinoma is relatively low. Early stage of poorly differentiated carcinoma has higher malignancy and risk of metastasis because the tumor occurs locally, but local or distant metastasis does not necessarily occur. For middle and late stage of cancer patients, most of them can have metastasis to local lymph nodes, distant organs and other organs, which can lead to the death of the patients in serious cases. Through early detection, early diagnosis and early treatment, low-differentiated cancer can prevent metastasis and improve the prognosis of the disease. Once discomfort occurs, one should consult the doctor in time and cooperate with the doctor’s treatment. Meanwhile, low-differentiated cancer can be prevented through regular medical checkups, quitting smoking and drinking, reasonable diet and supplementation of nutrition.