To investigate the recent clinical efficacy of sodium alginate microspheres (KMG) applied in the interventional treatment of gynecological intermediate and advanced malignant tumors. Methods All 18 patients with gynecological intermediate and advanced malignant tumors underwent chemoembolization with sodium alginate microspheres (KMG) plus chemotherapeutic drugs, and the efficacy was evaluated and the surgical resection rate was observed. Results Among the 18 patients, 9 cases were surgically resected after interventional treatment, with a symptom relief rate of 94.44% and a mass regression efficiency of 77.78%. Conclusion Sodium alginate microspheres (KMG) were applied in the treatment of gynecologic mid- to late-stage malignant tumors with obvious efficacy, safety, effectiveness, and ease of operation. Gynecologic malignant tumors are one of the life-threatening diseases in women, and sometimes the tumors start insidiously and are often in advanced stages when they are seen, and some patients have lost the opportunity of surgery. Interventional therapy provides a safe and effective method for such patients. The appropriate use of embolic agents in interventional therapy has a significant impact on the outcome. There are many kinds of embolic agents, the more commonly used ones are gelatin sea surface, polyvinyl alcohol (PVA), iodized oil, etc., but they also have some disadvantages each. We applied the new embolic agent sodium alginate microspheres (KMG) to intervene in the treatment of advanced gynecological malignancies and achieved better recent clinical efficacy. 1. Materials and methods 1.1 Clinical data 18 patients with advanced gynecological malignancies, including 5 cases of cervical cancer stage II and 2 cases of stage III according to FIGD stage. There were 3 cases of stage II uterine body cancer, 6 cases of stage II ovarian cancer, and 2 cases of endometrial cancer. The main clinical symptoms were irregular vague pain in the lower abdomen in the early stage, aggravated by menstruation, increased menstrual flow and long menstrual periods. In severe cases, irregular vaginal bleeding was observed. 1.2 Treatment method: Seldinger’s puncture method was used to puncture through the femoral artery to identify the diseased blood supply artery (e.g. uterine artery), and then super-selective cannulation was performed through the catheter to both uterine arteries or internal iliac artery for chemoembolization respectively. Chemotherapy regimen: Different chemotherapy regimens are used according to different tumor pathologies. Sodium alginate microspheres (KMG) with a diameter of 300-500 um were used. 2-3 weeks later, surgery was performed for those who could be operated, and the intervention was repeated once in 6-8 weeks if necessary. 1.3 Efficacy determination 1.3.1 Symptom remission: Symptom refers to the pain, swelling, vaginal bleeding and fluid, and difficulty in urination and defecation caused by the tumor. 0 is complete remission, 1 is moderate remission, 2 is mild remission, 3 is no remission, and 4 is deterioration. 1.3.2 Recent efficacy Combined with gynecological examination and CT, the tumor regression was observed 2 to 3 weeks after intervention. According to the WTO standard, complete remission (CR) was defined as complete disappearance of the tumor and maintained for more than 4 weeks; partial remission (PR) was defined as a 50% or more reduction in the size of the tumor and maintained for more than 4 weeks; stable (SD) was defined as no more than 25% reduction or increase in the size of the tumor and no new tumor foci were found during the treatment period; progressive (PD) was defined as more than 25% increase in the size of the tumor or the appearance of new foci; the total efficiency was CR+PR. The overall efficiency was CR+PR. 2. Results: 17 patients were in clinical remission and 9 patients were operated after intervention. The remission of symptoms and masses are shown in Tables 1 and 2, respectively. 3. Discussion 3. 1 The value of interventional therapy for mid- to late-stage gynecologic malignancies Many mid- to late-stage gynecologic malignancies are inoperable or difficult to operate because of the infiltration of tumor cells into the surrounding organs, and conventional intravenous chemotherapy cannot effectively kill cancer cells due to the low concentration of local anti-cancer drugs in cancer tissues. With the development of interventional radiology technology in recent years, arterial cannulation chemoembolization therapy has become one of the main means for the treatment of middle and late stage gynecological malignant tumors and has achieved good clinical treatment effect. It has reversed the clinical stage of some cases to obtain the opportunity of surgery and created the conditions for further treatment. Since some advanced gynecological malignant tumors have completely filled the pelvic cavity, the tumors directly adhere to and invade the uterus, rectum, bladder wall and pelvic wall, and are closely connected with the small vessels of internal iliac artery, uterine artery, upper and lower bladder artery and occluded artery, their growth is mainly related to the blood supply of these arteries. On the one hand, the catheter can reach the area closest to the tumor, and the drug can enter the tumor and be distributed around it rapidly by using the abundant collateral circulation around it. On the other hand, the local drug concentration is high. The local concentration is 89 times higher than that of systemic intravenous chemotherapy, and the effect is concentrated. Because the drug concentration is within a certain range, a 1-fold increase in local drug concentration can increase the anti-cancer effect by 10 times. This can make chemotherapy drugs concentrate around tumor tissues and kill tumor cells directly, so that the tumor can shrink or disappear and achieve the treatment purpose. In addition, after entering the circulatory system, the arterial infusion drugs will pass through other tissues of the body with the blood flow, which also have certain preventive and curative effects on distant metastases. Finally, arterial infusion can significantly increase the concentration of drugs in retroperitoneal lymph nodes and omental lymph nodes, which further enhances the defense ability of lymph nodes against cancer cell invasion and effectively prevents lymph node metastasis. At the same time, embolization with drug-carrying microspheres can increase the local drug concentration while blocking the blood supply to the tumor, causing ischemic and hypoxic necrosis of the tumor, and at the same time reducing the blood flow to flush the drug inside the tumor, prolonging the residence time of the drug inside the tumor, so that it can fully contact with the tumor tissue for a long time and exert a greater killing effect. Improve the efficacy of treatment. We applied super-selective internal iliac artery cannulation chemotherapy to treat 18 cases of mid- to late-stage gynecological malignancies. After treatment, 9 cases had significant tumor shrinkage and clear boundaries with surrounding tissues, all of which were feasible for hysterectomy, double adnexal resection, large omentum and appendectomy, 8 cases had residual lesions and 1 case was negative. The treatment effect was obvious. 3.2 Advantages of KMG in the treatment of middle and late stage gynecological malignant tumors In the interventional treatment of middle and late stage gynecological malignant tumors, drug-laden microspheres are used to embolize the small arteries at the tumor lesions to cut off the nutrition of the tumor cells and slow down or inhibit the growth of the tumor cells, and at the same time, because the drugs in the microspheres are continuously released from the obstruction site, the therapeutic concentration in the tumor tissue is maintained for a long time and the distribution of the drugs in other tissues is minimized. The drug microspheres can greatly improve the efficacy of chemotherapy drugs and reduce the toxic side effects. The good performance of drug microspheres makes them an ideal embolic agent for transcatheter arterial embolization procedures. The commonly used embolic agents include gelatin sponges, iodized oil, polyvinyl alcohol microspheres (PVA) and KMG. Gelatin sponges have been used to treat gynecological malignancies with good efficacy. However, this gelatin sponge crushed fast as embolic agent and drug carrier its particles are larger (diameter 1~2ml) and less uniform, can not completely embolize tumor micro-artery, and tumor can also establish collateral microcirculation, tumor ischemia is not serious, not easy to necrosis, easy to recur. Polyvinyl alcohol microspheres (PVA): the size of PVA microspheres is different from the site of embolization of blood vessels. Theoretically, embolization with PVA microspheres can cause complete necrosis of tumor, which can play the role of “chemoembolization” to tumor tissue. However, it is easy to block the tube because of the rapid expansion rate during operation, and it is non-degradable in the body and permanently embolized. Iodized oil. Iodinated oil can carry chemotherapeutic drugs to selectively stop in the blood sinus of malignant tumor, so that it has the effect of guiding chemotherapy. The use of iodinated emulsion embolization chemotherapy for gynecologic malignancies has achieved some efficacy, but some scholars suggest that it should be used with caution because of its ability to be lost in a short period of time and the presence of relatively serious complications. Because iodine oil can embolize capillary beds, a series of complications can occur when blood vessels are embolized, mainly in: (1) ischemic necrosis after arterial embolization; (2) nerve injury. According to the integrity of the neurotrophic vessels, complete occlusion of the anterior and posterior branches of the internal iliac artery can cause ischemic damage to the sciatic nerve, so embolization of all the anterior and posterior branches of the internal iliac artery bilaterally can produce paralysis and paralysis of the lower extremities as well as the risk of Brown-Sequard syndrome. Therefore, the patency of blood flow in the small anterior capillary artery plexus must be ensured. (3) Necrosis and perforation of the corresponding organs in the pelvis. Sodium alginate microspheres (KMG) vascular embolic agent, is a sodium salt of polyanionic polysaccharide (alginate) extracted from natural brown algae. With the advantages of uniform particle size and natural degradability, it has been widely used in clinical practice. The microspheres gradually disappear after 3~6 months in the form of molecular chains of non-toxic degradation. Compared with other embolic agents, KMG has the following advantages when used in embolization therapy: (1) KMG is a bio-derived material, which is free of foreign body irritation and has good biocompatibility. (2) KMG can be selected according to the clinical selection of microspheres with different size particles, overcoming the disadvantage of uneven size of gelatin sponge particles. (3) Compared with PVA, KMG can swell rapidly after entering the blood, which makes it better targeting and more complete embolization at the site of target vessels. Because the expansion rate is slower than PVA after mixing with contrast agent, it is easier to operate during the release process and not easy to block the tube, which is conducive to the smooth embolization. (4) Compared with superfluid iodine oil, firstly, it can overcome the disadvantage of superfluid iodine oil loss in target vessels and enhance the effect of embolization vessels to improve the therapeutic effect of embolization. Secondly, the size of embolized vessels is moderate, which overcomes some effects caused by excessive embolization of terminal embolization agents. Our application of KMG treatment of 18 patients with definite efficacy and significantly reduced side effects. It is worth applying.