Cancer is one of the main diseases that threaten the health of human.In order to increase the cure rate of cancer,the accurate therapy of cancer must be developed speedily.The most effective method for curing cancer is intensity modulated radiation therapy(IMRT),which can increase the local control rate of cancer and decrease complications of tissues.IMRT is considered to be an important breakthrough in cancer therapy.The dose produced by it is better than 3D-CRT and can achieves better results of therapy,which has been confirmed in the clinical therapies of head cancer,neck cancer,prostate cancer,breast cancer,cervical cancer and pancreas cancer etc.The developing course of IMRT,the methods of intensity modulation,the enforcement process of IMRT and the feasibility test of therapy plans are emphatically introduced.

Objective To prepare a radiofrequency (RF) ablation probe guided by endoscopic ultrasonography (EUS) and to evaluate its efficacy and safety. Methods A modified 19-gauge needle ( Olympus) was used, which was electrically insulated with shrink tubing, with the tip of lcm naked. The insulation was tested, and the current signal was stable. Three rabbits were anesthetized with 8% chloral hydrate ( 3 ml/kg) intraperitoneally, fixed on the dissecting table. A standard neutral pad was applied to the thigh of the rabbit to complete the electrical circuit, both the pad and the needle electrode connected with RF generator. After anesthesia was ready, the needle was advanced through the gastric wall into the liver. Ablations were performed three times in the same zone. Extent and tissue lesion were measured after ablation. Results Ablation could be successfully performed by the needle electrode, with brown lesions surrounded by normal hepatic tissue. The mean diameter of the ablated zone in the liver was 1.0 cm× 1.2 cm. After ablation,specimens along the passage were subjected to NADH staining, and no lesions were found. HE and NADH staining showed no viable cells in the central ablation area. Conclusion With the advance of the technology and selection of materials, an EUS-guided needle electrode can be made. This preliminary animal trial demonstrates that radiofrequency ablation can be performed effectively and safely by using this EUS-guided needle electrode.

Objective To determine the power-time-ablation scope correlogram of a water-cooled single needle electrode radiofrequency (RF) ablation system and to establish a theoretical basis for its practical application.Methods RF ablations were performed using a water-cooled single needle electrode radiofrequency ablation system developed by the authors using fresh ox liver as well as liver and muscles of healthy adult New Zealand white rabbits.The temperature of the ablation area was monitored using a multichannel thermometric system.The maximum ablation scope was determined by detecting the rim at which the temperature was no less than 50 °C.The specific absorption rate (SAR) of the isolated liver tissue was calculated.Results In the treatment voltage range of 100-130V,the process was smooth and steady.No impedance variation was obvious.The maximum diameter of a single ablation was 51 cm.With the treatment voltage at 140-170 V,a larger ablation area could be reached in less time,but eventually the impedance began to increase while the ablation area was no longer expanded.When the treatment voltage reached the range of 180-200 V the impedance almost always increased rapidly out of limits,and the treatment system stopped automatically.The measured SAR value was consistent with the theoretical value.Pathology confirmed that both liver tissue and muscle tissue manifested typical coagulative necrosis.Conclusions The power amplifier,cooling,thermometric and control sections of the RF ablation system worked stably,and the practical ablation effect met the design and clinical treatment requirements.

ObjectiveThe efficacy and safety of nitrous oxide-sedated transnasal gastroscopy for high-risk patients of intravenous anesthesia were evaluated. MethodsA total of 157 patients were randomly assigned to the nitrous oxide group ( n =80) and the oxygen group ( n =77). Heart rate, blood oxygen saturation, blood pressure and electrocardiogram were monitored. Complications in both groups were recorded.Satisfaction degrees of patients and endoscopy physicians were evaluated with a questionnaire and visual analog scale (VAS) score. The questionnaire questions for physicians included the procedure evaluation ( steady, ok, unsteady). Patients' questionnaire questions included discomfort (light, moderate, severe), the patients' tolerance ( fine, moderate, weak) and the patients' willingness to undergo a second procedure. Statistical analysis was performed between the two groups. ResultsSix of the toal 157 patients were removed because of the operation failure (difficulty in access to nasal cavity in 5 patients and nose bleeding in one patient), 151 patients underwent the transnasal gastroscopy successfully and completed the questionnaires. In experimental group, there were 37 males and 41 females (mean age was 67.7 years, ranging 16-88 years, 7 patients were grade 1 of ASA, 61 were grade 2, and 11 were grade 3). In the control group, there were 36 males and 37 females (mean age was 67.9 years, ranging 17-86 years, 6 patients were grade 1 of ASA, 57 were grade 2, and 9 were grade 3). There was no differences in sex, average age and ASA grade between the two groups (P ＞ 0. 05 ). There was no difference in the mean operation time between the two groups, either (200. 1 s vs 200. 3 s) ( P ＞ 0. 05 ). There were no significant differences between the two groups in changes of blood oxygen saturation, blood pressure, electrocardiogram and complication rates ( P ＞ 0. 05 ).Both physicians' and patients' positive evaluations of the experimental group were more than that of the control (P ＜ 0. 05 ), while physicians' and patients' negative evaluations of the experimental group were less than the control (P ＜0. 05). VAS of physicians' satisfaction in the experimental group was higher than that of the control group (84 vs 70, t =14. 67, P ＜ 0. 05), and VAS of patients' satisfaction in the experimental group was superior to the control group (82 vs 71, t =11.56, P ＜ 0. 05). The number of patients wiring to undergo a second procedure in the experimental group was higher than that of the control (89. 7％ vs 69. 9％, P ＜ 0. 05). ConclusionNitrous oxide-sedated transnasal endoscopy is an effective and safe procedure for high risk patients of intravenous anesthesia.

ObjectiveTo assess the diagnostic value of EUS for pancreatic neuroendocrine tumors.MethodsClinical data of 26 patients with final diagnosis of pancreatic neuroendocrine tumors,who had underwent EUS and EUS-FNA,were retrospectively analyzed.Results On EUS,pancreatic neuroendocrine tumors presented as hypoechoic masses with clear margins and rich blood flow.Of the 26 pancreatic lesions,3 were in the head,2 in unicate process,2 in neck,11 in body and 8 in tail.The tumors presented with function in 16 ( mean size 9 mm),and on function in 10 ( mean size 29 mm).EUS-FNA yeilded positive results in 22 patients and negative in 4.The accuracy rate of EUS for preoperative localization was 100％ in 23 patients who underwent surgery.ConclusionEUS can provide accurate preoperative localization and pathologic evidence for pancreatic neuroendocrine tumors.

OBJECTIVE:To promote the supervision and management of clinical trial by institution. METHODS:The structure and function of clinical trial management system(CTMS)developed by our hospital and other enterprise together were analyzed to evaluate the application and operation result of CTMS. RESULTS & CONCLUSIONS:CTMS of our hospital is made up of foun-dation,efficiency and strategy. It is equipped with role allocation,information exchange and report,information warning,drug tracking,clinical trial process control,quality control of electronic record,electronic signature and integration and connection with other system,etc. Relevant operation procedure is established to promote standardization and institutionalization of CTMS. Due to the application of CTMS,the cooperation among departments become smoother,and management level have been enhanced in dai-ly management,pharmacy management,subjects and document administration. It also simplifies the work of researcher and reduc-es the human error by the autogeneration of trial records and tables with the system. Consequently,the monitor coveraged through-out all the trial process.

Objective To evaluate the safety and efficacy of carbon dioxide (CO2) used as an alternative to air in the gastric endoscopic submucosal dissection (ESD). Methods 80 cases underwent ESD treatment were randomly as-signed to two groups, 40 cases in CO2 group and 40 in air group. Arterial blood CO2 partial pressure was measured preoperative, intraoperative and postoperative respectively. Visual analog scale (VAS) was used to record patients the degree of abdominal pain and distention at 1 h, 6 h and 24 h after operation in each group. The incidence of com-plications were evaluated. Regular follow up were scheduled in all the patients. Results There was no significant dif-ference in degree of abdominal pain score and the CO2 partial pressure between the two groups. The abdominal dis-tension scores of CO2 group were significant lower than air group at 1 h, 6 h after the ESD procedure. There were no statistically significant difference in the incidence rate of complications. Conclusion The utilization of CO2 in gas in-sufflation during gastric ESD is safe. CO2 insufflation can significant reduce the postoperative abdominal distension and improve the quality of postoperative recovery.

Objective To evaluate the short-term safety and efficacy of endoscopic implantation of self-expandable metallic stent (SEMs) for malignant colorectal obstruction.Methods A total of 208 patients who had undergone endoscopic SEMs implantation for malignant colonic obstruction from January 2012 to May 2014 at the endoscopy center of Shengjing hospital were enrolled.The technical and clinical success rate and the complications were reviewed.Results The technical and clinical success rates were 99.04％ (206/208) and 96.15％ (200/208), respectively.Abdominal pain, perforation and bleeding were the most common post-procedure complications, the rates of which were 13.46％ (28/208), 2.88％ (6/208), 1.92％ (4/208), respectively.The abdominal pain in most patients was self-relieving except for 6 patients with perforation of colon.Patients with perforation were cured by emergency surgery.One patient with intraperitoneal hemorrhage was also cured by emergency surgery, the other patients developing bleeding recovered themselves.Conclusion The success rate of endoscopic SEMs implantation is satisfactory in the study.As a bridge to surgery or a palliative care method, endoscopic SEMs implantation is effective and safe for malignant colorectal obstruction.

Objective To evaluate the efficacy of endoscopic metal stent implantation for afferent limb obstruction after pancreaticoduodenectomy(PD). Methods A retrospective analysis of 5 patients with afferent limb obstruction after PD treated by endoscopic metal stent implantation was performed.Data of each patient was reviewed including the records of the endoscopic procedure,the complications and the clinical outcomes. Results All the metal stents were implanted successfully in the 5 patients. The abdominal disten-sion and cholangeitis were well relieved in all the patients. The liver function improved in all the patients in 3 to 5 days.No abdominal discomfort,bleeding,perforation,or stent dislocation occurred.CT scan showed that all stents were well expanded.The survival time of the 5 patients were 3 to 8 months,and 4. 6 months on av-erage. There was no recurrence of afferent limb obstruction. Conclusion For afferent limb obstruction after PD,endoscopic metal stent implantation is effective in relieving obstruction,the symptoms,and improving the quality of life.

Objective To investigate the incidence of electrocoagulation syndrome after endoscopic submucosal dissection (ESD) in the colorectal laterally spreading tumors (LST) and the risk factors. Methods Data of 51 patients with coloretral LST,treated with ESD from January 2010 to May 2014 at Shengjing hospital affiliated to China Medical University,were reviewed.The incidence of electrocoagulation syndrome was analyzed and logistic regression was used to evaluate risk.Results The incidence of electro-coagulation syndrome was 9.8%(5 /51).The incidence of tumors in the rectal area(7.1%,2 /28)was lower than that of the left half colon (12.5%,1 /8),and the right colon (13.3%,2 /15).Multivariable logistic regression analysis showed that the independent risk factors for the development of electrocoagulation syndrome were LST located in non-rectum area (OR =1.655,P <1.655),lesion size larger than 25 mm (OR =1.028, P <0.05),the operation time longer than 129 min (OR =1.016,P <0.05),age older than 62 year old (OR =0.987,P <0.05).Conclusion For the patients aged over 62 year old,lesion size larger than 25 mm,the operation time longer than 129 min and LST located outside the rectum,the mucous membrane should be separated from the muscularis propria in the ESD procedure to reduce electrocoagulation time as much as possible. In the postoperative period,patients need fasting,fluid replacement support,and prevention of post endoscopic submucosal dissection electrocoagulation syndrome (PEECS).