High-intensity focused ultrasound (HIFU) as a new means of tumor treatment makes it possible to provide treatment for some tumor patients who have lost the opportunity of surgery, old age and frailty and lost the opportunity of radiotherapy and chemotherapy, and it has got more satisfactory clinical treatment effect. From July 2009 to February 2010, our hospital applied this technology to treat 92 patients with primary or secondary solid tumors in the abdomen and achieved good therapeutic effect, which is now reported as follows. 1. Materials and methods 1.1 General information 92 cases of abdominal solid tumors admitted to our hospital from July 2009 to January 2010 were selected, 58 cases were male and 34 cases were female, aged 28-71 years old, with a median age of 51 years old. All cases were diagnosed by pathology, including 51 cases of primary liver cancer, 29 cases of pancreatic cancer, and 12 cases of retroperitoneal lymph node metastases (the primary diseases were: colorectal cancer, gastric cancer, cholangiocarcinoma, and malignant gastrointestinal mesenchymal stromal cell tumor, respectively); all of them were accompanied by pain in the epigastric region or the lower back; all of them had ultrasound examination showing the lesions, with a diameter of at least 2.5 cm and at most 12.5 cm, with an average of (6) to (6) years old. 12.5 cm, average (6.8±1.1) cm, Karnofsky score ≥60 in all cases, expected survival time ≥3 months; electrocardiogram was normal, no bleeding tendency. 1.2 Instruments, equipment and main parameters HIFU treatment adopts JC200 high-intensity focused ultrasound tumor treatment system developed by Chongqing Haifu Medical Equipment Co. The system adopts ultrasonic positioning, ultrasonic frequency 1MHz±10, input power 0.5~2kW, focal sound intensity 900~4000 W/cm, effective treatment depth 1~15 cm, the treatment medium is degassed tap water, and the unit launching time (t1) is generally in the range of 0.1~0.2 S. Duty cycle time (t2) t2：tl≈1:1:2:1, and the number of times per point (N) is 30~80 times. ～N) 30~80 times. The measured focal point was 3mm×3mm×8mm.Pre- and post-treatment examinations and post-treatment follow-up examinations were performed using a TOSHIBA-240 ultrasonic diagnostic instrument and a spiral CT.1.3 Treatment MethodsThe treatment plan was formulated jointly according to the patient’s general condition, the location of the lesion as determined by ultrasound, its size, morphology, and relationship with neighboring organs, etc. The treatment plan included the scope of treatment, the level of treatment, and the level of the treatment. The treatment plan includes the treatment range, the number of treatment levels, the area of each level and the number of treatment points. Finally, under the automatic control of the computer, each level within the target area is treated from deep to shallow until the whole predetermined treatment target area is covered. 1.3.1 Therapeutic Position The patient is placed in the attached horizontal position, under intravenous compound anesthesia, and ultrasonically positioned against the on-board ultrasound positioning probe to determine the scope, size and level of treatment. 1.3.2 Scope of treatment Determine the scope of HIFU treatment according to the location, size, morphology and proximity of the lesions seen on the ultrasound scan. 1.3.3 Number of treatments Patients were treated once a day or once every other day, and 92 patients received a total of 368 HIFU treatments, with a minimum of 1 treatment and a maximum of 12 treatments. 1.4 Efficacy evaluation criteria and follow-up 1.4.1 Evaluation of recent efficacy According to the WHO criteria [1], complete remission (CR), partial remission (PR), stabilization (SD), and progression (PD), respectively, CR+PR was considered effective (RR), and CR+PR+SD was considered disease control (DCR). 1.4.2 Evaluation of the degree of pain relief The local pain symptoms of the patients before and after treatment were scored using the VAS pain scoring method. Patients self-selected numbers from 0 to 10 to formulate the degree of pain, i.e., 0 is no pain, 1 to 3 is mild pain, 4 to 6 is moderate pain, and 7 to 10 is severe pain. Evaluation of pain relief: 0 degree, no relief; 1 degree, mild relief (pain reduction of about 1/4); 2 degrees, moderate relief (pain reduction of about 1/2); 3 degrees, obvious relief (pain reduction of about 3/4 or more); 4 degrees, complete relief (pain disappearance). 1.4.3 Follow-up All cases were followed up for more than 2 months. 1.5 Quality of life score Scored by Karnofsky (KPS). No symptoms and signs (100); able to carry out normal activities, with slight symptoms and signs (90); barely able to carry out normal activities, with symptoms and signs (80); able to take care of themselves, but not able to maintain a normal life and work (70); sometimes needing help, but most of the time able to take care of themselves (60); often needing people to take care of them (50), not able to take care of themselves, and needing special care (40); seriously unable to take care of themselves (30); seriously ill, not able to take care of themselves (30); severely ill, not able to take care of themselves (30); seriously ill, not able to take care of themselves (30) (30); seriously ill and need to be hospitalized for active supportive treatment (20). 1.6 Statistical methods SPSS 10.0 statistical analysis software was used, and t-test or rank-sum test was used. 2, Results 2.1 Local efficacy 92 patients underwent a total of 368 times of treatment, an average of 4 times per case, of which 11 cases of PR (11.6%), 50 cases of SD (54.5 ), 31 cases of PD (33.7 ), the whole group had no CR cases, RR l1.4, DCR was 65.7. 2.2 The degree of pain relief of the 92 patients selected were accompanied by abdominal or low back pain symptoms, the pain score before treatment: 7.0 ± 2.1; after treatment all patients in the case of drug pain relief measures remain unchanged, the pain score fell to 4.1 ± 1.0 (P50 ℃ high temperature, through thermal effects, cavitation effects and mechanical effects and other physical effects is the tissue or tumor tissues undergo coagulation, denaturation necrosis, so as to achieve the purpose of treatment [2.2]. So as to achieve the therapeutic purpose [2]. Relevant basic research has confirmed that it can also cause other biological effects such as induction of apoptosis, upregulation of cellular immune function [3]. In recent years, clinical studies have shown that HIFU has been widely recognized as a local means [4], which can rapidly relieve pain and improve the quality of life while controlling the local lesions of tumors without obvious adverse effects [5,6,7]. The use of JC200 focused ultrasound tumor treatment system will kill the malignant tumors of multi-organ entities in the abdominal cavity, causing degeneration and coagulative necrosis of malignant tumor tissues, and has achieved good clinical efficacy for middle and late stage malignant tumors. All of the 92 patients in our group were intermediate and advanced progressive malignant solid tumors, and such patients could not tolerate surgery or refused to undergo surgery, or had postoperative recurrence and postoperative residuals, and had been difficult to tolerate regular radiotherapy. After HIFU treatment, it maximally kills the tumor load, improves the body condition, reduces cancer pain, and prolongs the survival period of tumor patients. In this group, 72 cases had different degrees of pain, and 95.8% of the pain was relieved after treatment. Except for one case of I0 scald, no perforation, hemorrhage, peritonitis, pancreatic fistula, severe burns and other adverse reactions occurred in this group, which showed good tolerance.Accurate mastery of the indications for HIFU treatment and precise positioning of the target area is the key to ensure the thoroughness of local treatment and reduce adverse reactions. For patients with multiple treatments, it is necessary to pay attention to the conditions of each treatment (step, row, layer distance) and the accuracy of the treatment range (X- and Y-axis treatment area), to ensure the consistency of the treatment process and the reproducibility of the patient’s position and the on-board ultrasound image, so as to ensure the articulation of the target area and avoid the omission of the target point and over-treatment. HIFU, as a candidate treatment for middle and advanced tumors that have lost the opportunity of traditional treatment, has attracted more and more attention in the field because of its non-invasive, non-systemic toxicity and side effects, and precise efficacy.HIFU is a cutting-edge technology-based new measure for treating tumors, and it has achieved promising efficacy in the treatment of certain tumors at present. However, HIFU, as a non-invasive technique for deep tumors in vivo, cannot ensure one-time complete resection of solid tumor lesions, which requires us to do in-depth research on ultrasound localization, resection range, treatment modality, etc. Intra-operative HIFU and interventional HIFU are likely to become an important means of treatment of solid tumors in the abdomen. The absorption and reflection of ultrasound is more complex and related to the interface of the tissue, and the density of the tissue vascular condition, etc. How to reasonably use the appropriate dose so that it can destroy the tumor, but also protect the normal tissue is the key to improve the therapeutic effect of HIFU. Although most studies concluded that HIFU does not promote metastasis, the relationship between HIFU and tumor metastasis and HIFU and immunity needs to be studied in depth. In addition, HIFU is a kind of local treatment, how to cooperate well with radiotherapy and how to arrange the treatment sequence remains to be explored. The development of surgical technology follows the evolutionary trajectory from giant invasive – invasive – minimally invasive – non-invasive, and the emergence of HIFU provides clinicians with a truly non-invasive means of treatment.The application of HIFU is not only limited to the direct treatment of malignant tumors, but also can be used for benign tumors and non-tumor diseases, such as palliation of malignant tumors with chronic pain, surgical hemostasis, etc. The recent technological developments and medical practices have made HIFU an important part of the medical practice. Recent technological development and medical practice have shown that the application of HIFU will play a pivotal role in the field of surgery in the future. We believe that with the development and popularization of HIFU technology, HIFU technology will better serve the cause of human health.