The effects of benign tumors are mainly related to the site of occurrence and secondary changes. If it occurs in important organs, it can also produce serious consequences. For example, benign tumor of gastrointestinal tract can cause intussusception and intestinal obstruction. Benign intracranial tumors such as meningioma and astrocytic glioma can compress brain tissue and obstruct the ventricular system, resulting in increased intracranial pressure and corresponding neurological symptoms. Secondary changes of benign tumors can also affect the body to different degrees. Adenocarcinoma polyps of the intestine and papillary tumors of the bladder can have ulcers on their surfaces and cause bleeding and infection. Malignant tumors have serious effects on the body because of immature differentiation, rapid growth, infiltration and destruction of organ structure and function, and metastasis can occur. In addition to local compression and obstruction symptoms similar to the benign tumors mentioned above, malignant tumors may also have fever, intractable pain, and a state of severe wasting, weakness, anemia and systemic failure in the late stage. Ectopic endocrine syndrome: Some non-endocrine gland tumors can produce and secrete hormones or hormone-like substances, causing clinical symptoms of endocrine disorder. These tumors are mostly malignant tumors, mostly cancer, such as gastric cancer, liver cancer, colon cancer, and also sarcoma, such as fibrosarcoma and smooth muscle sarcoma. In addition tumors of the APUD system (diffuse neuroendocrine system) can also produce biogenic amines or peptide hormones, such as carcinoid tumors and pheochromocytomas. Difference between benign and malignant tumors: The biological characteristics of benign tumors and malignant tumors are obviously different, and thus their effects on the organism are also different. It is important to distinguish benign tumors from malignant tumors for the diagnosis and treatment of tumors. 1.Degree of tissue differentiation: benign tumors are well differentiated, with small heterogeneity and similar morphology to the original tissues; malignant tumors are poorly differentiated, with large heterogeneity and large difference in morphology from the original tissues. 2.Nuclear splitting image: benign tumors have no or few nuclear splitting images, and no pathological nuclear splitting images are seen; malignant tumors have many nuclear splitting images, and pathological nuclear splitting images are seen. 3.Growth speed: benign tumor is slow; malignant tumor is faster. 4.Growth mode: benign tumors are often seen as swelling and exophytic growth, the former often has envelope formation and is usually clearly demarcated from surrounding tissues, so it can usually be pushed; malignant tumors are infiltrative and exophytic growth, the former has no envelope formation and is usually not clearly demarcated from surrounding tissues, so it usually cannot be pushed, the latter is accompanied by infiltrative growth. 5.Secondary changes: necrosis and bleeding rarely occur in benign tumors; necrosis, bleeding and ulcer formation often occur in malignant tumors. 6.Metastasis: benign tumors do not metastasize; malignant tumors often have metastasis. 7.Recurrence: benign tumors rarely recur after surgery; malignant tumors often recur after surgery and other treatments. 8.Impact on organism: benign tumor is small, mainly causes local compression or obstruction, if it occurs in important organs, it can also cause serious consequences; malignant tumor is large, besides compression and obstruction, it can also destroy the tissues at the origin and metastasis, cause necrosis and bleeding combined with infection, and even cause cachexia.