Radiotherapy can cause functional and morphological changes in the brain tissues of patients with primary or metastatic malignant brain tumors, leading to radiation-induced brain injury. However, the pathogenesis of radiation-induced brain injury has not yet been unanimously determined, and its research advances and treatment protocols are yet to be elucidated and improved. In this study, we explore the pathogenesis of radiation-induced brain injury from the perspective of vascular injury, inflammatory reactions, neuronal dysfunction, glial cell injury, and gut microbiota and reviewed the advances in research on its treatment and prevention. The purpose is to provide a reference and theoretical basis for the research and clinical diagnosis and treatment of radiation-induced brain injury.

Objective:Analyze the cancer screening status of the cancer screening program in urban areas in Shaanxi province in 2019-2020.Methods:The early diagnosis and early treatment project for urban cancers carried out high-risk population screening for 5 types of high-incidence malignant tumors (breast cancer, lung cancer, upper gastrointestinal cancer, liver cancer, and colorectal cancer) in urban areas. Three prefecture-level cities in Shaanxi province with a population of over 1 million (Xi'an, Baoji, and Shangluo) were selected, and 4 communities with a relatively good working foundation were selected in each city. The general population aged 45-74 years was surveyed on the principles of informed consent and voluntariness, and high-risk groups identified through the questionnaire were further subjected to free endoscopy, ultrasound, CT, and other clinical screenings. The high-risk rates, screening compliance rates, and positive detection rates of the above 5 types of malignant tumors were analyzed.Results:A total of 19 632 people completed the survey effectively, with the proportion of male participants (40.0%) lower than that of females (60.0%). A total of 10 102 high-risk groups were identified, with an initial screening high-risk rate of 51.5%, and the high-risk rates for the 5 types of cancers were 24.1% for breast cancer, 28.6% for lung cancer, 9.1% for upper gastrointestinal cancer, 4.0% for liver cancer, and 20.0% for colorectal cancer. Among the 14 960 person-time initially assessed as high-risk, 5 129 person-time received clinical screening, with a screening compliance rate of 34.3%. The number of people receiving clinical screening and the screening compliance rates for the 5 types of cancers were 1 192 (41.9%) for breast cancer, 2 081 (37.1%) for lung cancer, 574 (32.0%) for upper gastrointestinal cancer, 404 (51.3%) for liver cancer, and 878 (22.3%) for colorectal cancer, with positive detection numbers and rates of 179 (15.0%) for breast, 289 (13.9%) for lung, 9 (1.6%) for upper gastrointestinal, 14 (3.5%) for suspected liver, and 67 (7.6%) for colorectal, respectively.Conclusion:The cancer screening status of the cancer screening program in urban areas in Shaanxi province is beneficial for the detection of precancerous lesions and early cancer patients, and improving the early diagnosis and treatment rate of patients, but the public participation rate is not high, and the project management model and technical plan need to be further improved.

Objective:Analyze the cancer screening status of the cancer screening program in urban areas in Shaanxi province in 2019-2020.Methods:The early diagnosis and early treatment project for urban cancers carried out high-risk population screening for 5 types of high-incidence malignant tumors (breast cancer, lung cancer, upper gastrointestinal cancer, liver cancer, and colorectal cancer) in urban areas. Three prefecture-level cities in Shaanxi province with a population of over 1 million (Xi'an, Baoji, and Shangluo) were selected, and 4 communities with a relatively good working foundation were selected in each city. The general population aged 45-74 years was surveyed on the principles of informed consent and voluntariness, and high-risk groups identified through the questionnaire were further subjected to free endoscopy, ultrasound, CT, and other clinical screenings. The high-risk rates, screening compliance rates, and positive detection rates of the above 5 types of malignant tumors were analyzed.Results:A total of 19 632 people completed the survey effectively, with the proportion of male participants (40.0%) lower than that of females (60.0%). A total of 10 102 high-risk groups were identified, with an initial screening high-risk rate of 51.5%, and the high-risk rates for the 5 types of cancers were 24.1% for breast cancer, 28.6% for lung cancer, 9.1% for upper gastrointestinal cancer, 4.0% for liver cancer, and 20.0% for colorectal cancer. Among the 14 960 person-time initially assessed as high-risk, 5 129 person-time received clinical screening, with a screening compliance rate of 34.3%. The number of people receiving clinical screening and the screening compliance rates for the 5 types of cancers were 1 192 (41.9%) for breast cancer, 2 081 (37.1%) for lung cancer, 574 (32.0%) for upper gastrointestinal cancer, 404 (51.3%) for liver cancer, and 878 (22.3%) for colorectal cancer, with positive detection numbers and rates of 179 (15.0%) for breast, 289 (13.9%) for lung, 9 (1.6%) for upper gastrointestinal, 14 (3.5%) for suspected liver, and 67 (7.6%) for colorectal, respectively.Conclusion:The cancer screening status of the cancer screening program in urban areas in Shaanxi province is beneficial for the detection of precancerous lesions and early cancer patients, and improving the early diagnosis and treatment rate of patients, but the public participation rate is not high, and the project management model and technical plan need to be further improved.

Objective:To evaluate the feasibility of a novel liver fiducial marker implantation method for internal fixation and removal of rabbit livers, in order to use in Cyberknife tracking therapy.Methods:Experiments were conducted in vivo and in vitro. In the in vivo experiment, three fiducial markers were implanted percutaneously in each liver of ten rabbits under anesthesia, and the fourth fiducial marker with an external catheter and fixed thin wire was implanted ten days later. After the reference group (the first and the second maker), and the casing group (the first and the fourth marker) were respectively registered and tracked with the Cyberknife, the implantation success rate, registration accuracy, and removal safety of fiducial markers were assessed. The tensile test was performed using liver in vitro by measuring the resistance required to dislodge the spring coil fiducial markers and the fiducial markers without spring coil from liver. Results:The intrahepatic catheter implantation and removal of fiducial marker in rabbit liver had a success rate of 100% and no distant migration. The operation-related and postoperative complications were not occurred. All fiducial markers were successfully traced. Compared to the reference group, the casing group had slightly higher translational errors in supero-inferior and antero-posterior directions ( Z=-11.77, -4.57, P<0.05), and lower translational errors in left-right direction ( Z=-2.52, P<0.05). The dislodgement forces for spring coil fiducial markers was (2.23±0.85) N, significantly different with (0.81±0.13) N for fiducial markers without spring coil ( Z=- 2.31, P < 0.05). Conclusions:The spiral coil structure provides superior fixation in the punctured needle channel, the thin line limits the distant displacement of the fiducial marker outside the liver, and the catheter establishes a channel for the removal. The general operation is simple and easy.

Objective:To investigate the necessity and feasibility of the virtual simulation teaching experiment software of the bronchoscopy intelligent navigation-based fiducial marker implantation technology in the clinical application of radiotherapy.Methods:This study developed a 3D virtual operation and interactive system using the Unity3D engine, tools including 3Dmax and Maya, and the SQL database. The scenes in the system were produced using the currently popular next-generation production process. Targeting the priorities and difficulties in the implantation of fiducial markers, the system developed in this study allowed for simulated demonstration and training based on 12 steps and 10 knowledge points. Internal tests and remote evaluation tests were adopted in this system to obtain the test result of each subject. Then, the application value of the system was analyzed based on the test result.Results:As of May 1, 2022, the system had received 2 409 views and 425 test participants, with an test completion rate of 100% and an experiment pass rate of 96.5%. Moreover, this system won unanimous praise from 167 users, primarily including the students majoring in multilevel medical imaging technology and medical imaging science from the Fujian Medical University, as well as the radiotherapy-related staff of this university.Conclusions:The virtual simulation teaching experiment software of the bronchoscopy intelligent navigation-based fiducial marker implantation technology can be applied to the teaching of students and the training of related professionals.

Objective:To analyze the diagnostic and prognostic value of routine bone marrow examination in patients with extranodal NK/T-cell lymphoma (ENKTCL) based on PET-CT staging.Methods:Clinical data of 186 patients who received bone marrow biopsy and bone marrow aspiration in Fujian Medical University Union Hospital from 2013 to 2021 were retrospectively analyzed. All patients were divided into bone marrow biopsy + bone marrow aspiration group ( n=186) and PET-CT + bone marrow biopsy group ( n=139). The sensitivity, specificity, positive and negative predictive values were compared between two groups. The data were analyzed and plotted. Survival analysis was performed using Kaplan-Meier method and log-rank test. Results:In the whole cohort, 45 patients were positive for bone marrow biopsy, and 30 of them were positive for bone marrow aspiration. A total of 141 patients who were negative for bone marrow biopsy also achieved negative results for bone marrow aspiration. A total of 139 patients completed PET-CT staging and bone marrow biopsy. And 30 patients were diagnosed with positive bone marrow by PET-CT, in which 22 of them were confirmed positive by bone marrow biopsy. Among 109 patients diagnosed with negative bone marrow by PET-CT, 5 of them were confirmed positive by bone marrow biopsy. All these cases were classified as stage Ⅳ due to distant metastases. PET-CT had a diagnostic sensitivity of 81.5%, a specificity of 92.9%, a positive predictive value of 73.3%, and a negative predictive value of 95.4%. Among early stage (Ⅰ-Ⅱ stage) patients diagnosed with PET-CT, all of them were negative for bone marrow biopsy (the negative predictive value was 100%). In stage Ⅳ patients ( n=55), the 1-year overall survival of patients with bone marrow involvement by bone marrow biopsy or PET-CT ( n=35) compared with their counterparts with the involvement of other organs ( n=20) was 28.7% vs.42.0% ( P=0.13), and 1-year progression free survival rates was 23.2% vs. 23.3% in ( P=0.94). Conclusions:Routine bone marrow biopsy does not change the original staging of patients with early stage ENKTCL based on PET-CT staging. Advanced stage patients with positive bone marrow biopsy tend to obtain worse prognosis, indicating that bone marrow biopsy still has certain value.

Objective:To explore the tracking accuracy of the surface optically guided tracking system (OGTS) in radiotherapy.Methods:Phantom verification and clinical trial verification were adopted. Specialized equipment was employed for the phantom verification. Specifically, the displacement of the optical markers as they moved from a predetermined position to the target position on the reflector ball platform was captured using the OGTS, and then the obtained displacement was compared with the fixed distance within the phantom to calculate the accuracy and repeatability of the OGTS. For the clinical trial verification, 45 patients treated with radiotherapy, which consisted of 15 cases with head, breast, and rectal tumors each, were selected to investigate the tracking accuracy and repeatability of the OGTS. For each patient, the values derived from the image-guided positioning system (IGPS) and the OGTS before and after image-guided setup error correction during three times of fractionated radiotherapy were randomly obtained. The translational errors of each error correction were also recorded. Before radiotherapy, patients′ setup errors were corrected and relevant data were obtained using the IGPS. The correction result of translation errors obtained using the IGPS served as a gold standard to verify the accuracy of the OGTS in monitoring the translational motion of patients. Finally, the comprehensive translational deviation of both method was calculated.Results:The phantom measurements showed that the comprehensive translational deviation for tracking accuracy and tracking repeatability of the OGTS had a maximum deviation and a standard deviation of 0.18 mm and 0.03 mm, respectively. The clinical trial result indicated that the tracking accuracy of IGPS and OGTS exhibited statistically significant differences only for the head in the z direction ( t = 2.21, P < 0.05). Conversely, no statistically significant differences were observed for the head in the remaining directions or for the breast and rectum in the three translational directions ( P > 0.05). The analysis showed that comprehensive translational deviations for the head, breast, and rectum derived from OGTS and IGPS were (0.91±0.62), (1.64±1.30), and (1.52±1.29) mm, respectively, satisfying the requirement that the deviations should be below 2 mm. Conclusions:The OGTS, featuring easy operation and high tracking accuracy, can assist the IGPS in real-time respiratory monitoring during radiotherapy.

Objective:To explore the feasibility of recoverable fiducial marker implantation guided using the intelligent navigation bronchoscopy technology in the Cyberknife Synchrony-based respiratory tracking.Methods:CT scans of an inflatable pig lung after anti-rot processing were obtained. Then, eight simulated tumor lesion sites were designed in the left and right lung lobes using intelligent navigation software, with four classified as the sputum bronchial environment group and four classified as the wet bronchial environment group. Based on the implantation principle of Cyberknife fiducial markers, 32 recoverable fiducial markers were implanted around various simulated tumor lesions via bronchus under intelligent guidance. Then, the end-expiratory state of the pig lung was simulated, the pig lung was scanned again to obtain CT images of the implanted recoverable fiducial markers, and the number of successfully implanted fiducial markers was recorded. Eight deliverable Synchrony treatment protocols were designed using the Cyberknife planning system (Multiplan v4.6), and then the pig lung with simulated respiratory movements was exposed to radiation. After radiation, the implanted recoverable fiducial markers were retrieved using the bronchoscopy technique, and the number of successfully retrieved fiducial markers was recorded. Moreover, the translational errors, rotational errors, and rigid body errors were extracted from the Cyberknife log file and analyzed.Results:No recoverable fiducial markers slipped or fell during the experiment. Thirty-two recoverable fiducial markers were successfully implanted and recovered under the guidance of intelligent navigation bronchoscopy, with implantation and recovery success rates of both 100%. Moreover, the tracking rate and rigid body errors of the fiducial markers were 100% and less than 5 mm, respectively. The data from the Cyberknife log file indicated that there was no significant difference between the sputum bronchial environment group and the wet bronchial environment group in the translational errors in the left-right direction, the rotational errors in the roll direction, and the rotational errors in the pitch direction ( P>0.05). Compared to the wet bronchial environment group, the sputum bronchial environment group had slightly higher translational errors in front-back ( Z=-3.57, P<0.01) and cranio-caudal ( Z=-2.53, P<0.05) directions, lower rotational errors along the yaw axis ( Z = -3.88, P < 0.01), and lower rigid body error ( Z=-3.32, P<0.01), and the differences were all statistically significant. Conclusions:The recoverable fiducial marker implantation guided using the intelligent navigation bronchoscopy technology is feasible. Recoverable fiducial markers are stable in the bronchus of the phantom, and the Cyberknife tracking precision can meet clinical requirements. Therefore, the recoverable fiducial marker implantation guided using the intelligent navigation bronchoscopy technology has promising prospects in clinical and teaching applications.

Objective:To develop a remote training system for CT simulation positioning of radiotherapy using virtual reality technology, and to explore a new method of medical training.Methods:The 3DMax and Maya were employed to establish the 3D model. The unity3D engine was adopted to develop 3D virtual operation and interaction system. Java spring MVC architecture was utilized as the system background service. MySQL was used as the background database system. The users were assigned into two roles: teacher and student, and the modes were divided into teaching and assessment modes.Results:The function of the system covered the whole process of CT simulation positioning, mainly including modules of patient information management, CT simulation positioning machine cognition, body position fixation technology, CT positioning scanning, and emergency handling, etc. Since it was put into use in 2018, the system has been running stably, with 14 920 pages views and an 86.66% pass rate. Compared with the traditional training, the training efficiency has been significantly improved and has received unanimous recognition.Conclusions:The remote training system can effectively improve the clinical practice ability and humanistic care ability of the trainees, which has good autonomy, sharing, and innovation. At present, the system has been put online and has strong popularization with prospects for broad application.

Objective To discuss the necessity and feasibility of application of virtual reality (VR) technology in the teaching course of radiotherapy technology based on the contradictions between the theory and practice of current teaching mode.Methods After in-depth analysis of the characteristics of the existing disciplinary teaching mode,VR technology was introduced to design software,glasses,operating handles and establish a special interactive platform. The teaching courses could be delivered via mobile phone side AR, helmet and AR, touch screen and PC virtual simulation with VR virtual simulation, etc. Six processes of radiotherapy were tested through online courses and offline groups to analyze the feasibility of this technology applied in the training of radiotherapy professionals. Results After the design of software and hardware and the analysis of test results,the online teaching could be utilized to write interactive programs,build virtual experience scenes, create course resource database and construct practical training courses and teaching system. The offline practice test could be applied to the simulation learning of feedback of the whole process, which possessed feasibility and development value. It could be applied to the theory and practice teaching of radiation therapy technology,making the teaching more convenient,vivid and intuitive. Conclusions VR technique combined with radiotherapy technology training can be delivered through online and offline teaching courses of theory and practice by using the plane and virtual simulation technology, which is convenient, quick and highly efficient and deserves widespread application.