Hemangioma is one of the most common benign tumors in infants and children, with an incidence rate of 10%. Due to the high incidence of hemangioma, which may cause a variety of physiological and psychological hazards in individuals, there are numerous treatment options, but all of them have certain deficiencies or adverse effects. The following is a brief introduction to the basic issues and treatment of hemangioma. 1 . Classification and pathology of hemangioma ： The incidence of hemangioma is higher in low birth weight infants and premature infants. Traditionally, hemangiomas have been classified as capillary hemangiomas, cavernous hemangiomas, trapezius hemangiomas and mixed hemangiomas, but this classification can hardly reflect the biological characteristics and clinical features of hemangiomas.1 In 1982, Mulliken divided the traditional hemangiomas into hemangiomas and vascular malformations based on the different characteristics of the biology, pathological histological features and clinical manifestations of vascular endothelial cells. This caused a fundamental change in the understanding and treatment of hemangioma, and this classification standard is now gradually recognized and accepted. The pathological process of infantile hemangioma is clinically manifested in 2 completely different phases, namely the proliferative phase and the receding phase. The proliferative phase of hemangioma is generally observed within 6 months to 1 year after birth, and is initially observed as a small red papule, followed by a gradual or rapid increase in size. After that, it enters the receding stage, and the clinical manifestation is that the growth of hemangioma gradually stops, the tumor starts to become smaller, the surface color changes from bright red to dark red, the skin on the surface of the lump wrinkles, and the volume starts to become smaller. 2.Treatment methods of infant hemangioma There are many kinds of hemangioma and various treatment methods. Since more than 1/2 of the hemangioma can fade away in vain, and surgery and other treatments may produce more serious sequelae than its own fading, such as scar growth and dysfunction, it is generally advocated to take a wait-and-see and palliative attitude in the early stage of hemangioma. However, when the growth of hemangioma threatens the life or organ function of the child, it should be treated promptly. The choice of clinical treatment for infantile hemangioma is related to a variety of factors, which should mainly depend on the lesion site, depth (superficial, deep, mixed), scope and size, staging, whether there is functional impairment, the treatment experience of physicians, the effectiveness of specific treatment methods and the mental and psychological burden of the child and his or her mound. The main treatment methods for hemangioma include: (1) surgical excision; (2) cryotherapy; (3) radiation and radionuclide therapy; (4) laser therapy; (5) injection therapy; (6) topical drug therapy; and (7) oral drug therapy. 2.1 Surgical resection Surgical resection of hemangioma requires strict control of the indications and weighing the value of surgery before deciding whether to choose surgical treatment. For hemangiomas affecting function and endangering life, hemangiomas with large residual lesions even after conservative treatment, hemangiomas with repeated bleeding or ulceration and all malignant hemangiomas, surgical resection is still the main method, and it works well for independent and small lesions. 2.2 Cryotherapy Cryotherapy for the treatment of hemangiomas originated in the 1960s. Its method is based on freezing hemangiomas with liquid nitrogen, which is also applied by a few scholars. Using the strong low temperature (-96℃) caused by the volatile effect of liquid nitrogen, which is usually below -20℃ in the state, the skin of the lesion area, hemangioma and the tissues around the hemangioma are condensed, which causes the formation of ice products in their cells and leads to the rupture of cell membranes, hypothermic shock, ischemia and hypoxic necrosis of tissue cells and the generation of immune response, which causes the destruction and death of tissue cells, and then the hemangioma disappears through the repair process of the organism. This method is prone to leave local scar and tissue contracture, and often leaves serious deformities and dysfunction after treatment in the eye, corner of the mouth, tip of the nose and ear. Since it is difficult to control the intensity and depth of freezing operation, and the resistance of tissues to low temperature varies, incomplete treatment, local scarring, deformity and dysfunction are often observed. 2.3 Radiation and radionuclide therapy The principle of radiation and radionuclide therapy for hemangioma is to use gamma rays generated by radionuclides to bombard the nucleus of the tissue in the lesion area, causing the DNA and RNA strands to break and terminate the synthesis of nuclear proteins, leading to cell death and disintegration, and then to achieve the therapeutic purpose through the tissue repair process. The common clinical methods of radiation and radionuclide treatment are: superficial X-ray irradiation, “Co local irradiation, “Sr dressing, “P colloid local injection, etc. After the treatment of hemangioma, the treated area is left with atrophic scar after radioactive damage and epidermal desquamation. For this kind of atrophic tissue and atrophic scar caused by radiation irradiation, some scholars recommend surgical excision, otherwise the possibility of cancer cannot be excluded. Since radionuclide therapy may lead to potential harm to the child, it is believed that it should be avoided in the treatment of hemangioma. 2.4 Laser treatment Because of the limited penetrating power of laser, laser treatment is mainly suitable for early-stage, superficial hemangiomas. Its principle is to use professional laser treatment equipment to make the oxygenated hemoglobin in blood absorb light energy to generate heat, which is conducted to the surrounding blood vessel wall to cause vascular damage, so as to achieve the purpose of treating hemangioma. The lasers currently used to treat cutaneous hemangioma are 532 nm Nd:YAG laser, pulsed dye laser, 1064 nm Nd:YAG laser, photodynamic therapy and intense pulsed light system. When treating hemangioma, it is better not to use large energy lasers to avoid large damage to the body. In addition, the early C02 laser was treated by the principle of cutting and vaporization, which had a high incidence of postoperative scarring and was difficult to achieve good results, and is now used sparingly. Because of the scarring problem brought by laser treatment of hemangioma and the difficulty in dealing with larger area and deeper thickness lesions, and even the danger of causing hemorrhage, the use of laser must be cautious and the indications should be strictly mastered. 2.5 Injection therapy Commonly used drugs for injection therapy of hemangioma include: ① sodium cod liver oil acid; ② kuheoling injection; ③ alum injection; ④ kuheoling yellow lotus injection; ⑤ sodium bicarbonate injection; ⑥ pinyamycin and bleomycin; ⑦ boiling water injection therapy; ⑧ urea injection; ⑨ glucocorticoid. In the early stage, sclerosing agents such as sodium cod liver oil acid are used to inject human hemangioma flesh to cause local vascular cavity embolization and endothelial cell necrosis so as to achieve therapeutic effect. This method is locally irritating and traumatic, and after treatment, there are risks of infection, tissue necrosis and scar formation due to local tumor necrosis, so it is less used now. In 2002, Martinez et al. first tried to apply imiquimod for the treatment of infantile hemangioma, and achieved more satisfactory results. Currently, many scholars use 5% imiquimod applied topically every other day to treat infantile hemangiomas. Its mechanism of action may be to induce hemangioma regression by producing a large number of cytokines, such as IFN-a, interleukin (II.)-6, and tumor necrosis factor (TNF)-a. Its main advantages are convenience, controllability and no local irritation, which is especially suitable for treating small and medium-sized hemangiomas in hidden parts of the body. 2.7 Oral drug therapy Oral hormone therapy has been the first-line drug for the treatment of severe large-area and multiple hemangiomas, mainly for large-area, multiple or invasive hemangiomas and life-threatening hemangiomas with congestive heart failure, consumptive coagulation dysfunction, thrombocytopenia, affecting vision or respiration and other important organ functions. This is mainly related to the fact that the mechanism of hormone therapy for hemangioma has not yet been elucidated. Oral hormones can cause some serious and temporary complications, including personality changes, fungal infections, hypertension, Cushing’s syndrome and gastrointestinal discomfort. Propranolol for hemangiomas Oral propranolol for hemangiomas was first discovered by LeauteLabreze et al. who found that while using propranolol to treat heart disease in two infants shortly after birth, the color of the hemangiomas in the two infants became lighter and less extensive. Subsequently, they applied propranolol to 9 children with facial hemangiomas showing a lightening of the color of the hemangiomas within 24 h and no serious adverse effects during treatment, with only a few cases of low blood pressure. Once this method was reported in the literature, it quickly attracted the attention of scholars from various countries, which led to a series of clinical applications and basic research on propranolol treatment of infantile hemangiomas. Some of the more serious and life-threatening infantile hemangiomas could be rapidly controlled after propranolol treatment. In conclusion, hemangioma treatment is developing in the direction of timely controlling tumor growth and promoting regression, while protecting patients’ physiological functions, not damaging their appearance, reducing adverse effects, and alleviating the psychological burden of children and their families. Meanwhile, with the extensification of mature animal models of hemangioma and the in-depth study of its biological characteristics, the mechanisms and effectiveness of various treatment methods will be further elucidated, so that the treatment methods of hemangioma will be continuously improved. Due to the different classification, pathogenesis and pathology of hemangioma, the choice of clinical treatment methods also varies and involves many factors, and there is no single method that can be applied to all types of hemangioma. Some hemangiomas can be treated with a single method to achieve better results, while some cannot achieve satisfactory results even if several methods are used in combination. Therefore, the overall understanding of the disease by clinicians also needs to be improved. When choosing hemangioma treatment methods, multiple methods should be used flexibly in combination with each other according to the specific situation. Both basic and clinical studies have shown that most children’s hemangiomas can regress on their own and generally do not require special treatment. Therefore, the clinical treatment of most children with hemangioma tumors tends to be more and more carefully considered, with particular emphasis on preventing overtreatment of lesions that can regress on their own and have a good prognosis. Except for those with large areas, rapid growth, or serious complications or psychological effects that require active treatment, the decision of whether to intervene therapeutically should be made carefully after close observation by a specialist.