1.Application value of MEX3A,CDX2,MUC2 and MUC5AC in judging cancerous gastric mucosal intestinal metaplasia
Mengyuan ZHANG ; Jiarui LIU ; Zhong ZHANG ; Lanlan JIAO ; Min ZHANG ; Wei BO ; Jiayu GOU ; Chengcheng WU ; Xudong YANG ; Xuguang WANG
China Modern Doctor 2024;62(10):1-5
Objective To investigate the correlation between MEX3A and differentiation characteristics of gastric cancer and intestinal metaplasia,and its combination with caudal-related homeobox transcription factor 2(CDX2)and mucin 2(MUC2)and mucin 5AC(MUC5AC)to determine the role of carcinogenic intestinal metaplasia.Methods From January 2010 to December 2014,a total of 410 cases of gastric cancer and paracarcinoma paraffin-embedded tissue samples were selected from the Central Hospital Affiliated to Shenyang Medical College and the Second Hospital Affiliated to Shenyang Medical College.According to pathological diagnosis,they were divided into control group(mild superficial gastritis,79 cases),intestinal metaplasia group(149 cases)and gastric cancer group(182 cases).The expressions of MEX3A,CDX2,MUC2 and MUC5AC were detected by immunohistochemistry.Results MEX3A was highly expressed in gastric cancer group and intestinal metaplasia group,especially diffuse gastric cancer,poorly differentiated gastric cancer and type Ⅲ intestinal metaplasia(P<0.05).CDX2 and MUC2 were highly expressed in gastric cancer group and intestinal metaplasia group,especially intestinal type gastric cancer,highly and moderately differentiated gastric cancer,type Ⅰ and type Ⅱ intestinal metaplasia(P<0.05).The expression of MUC5AC was high in control group and low in gastric cancer group and intestinal metaplasia group,especially in intestinal type gastric cancer,type Ⅰ and type Ⅲ intestinal metaplasia(P<0.05).Gastric cancer and intestinal metaplasia differentiation were negatively correlated with MEX3A and MUC5AC expression,but positively correlated with CDX2 and MUC2 expression(P<0.05).MEX3A was negatively correlated with the expression of CDX2 and MUC2,and positively correlated with the expression of MUC5AC in gastric cancer(P<0.05).MEX3A was negatively correlated with the expression of CDX2 and MUC2 in intestinal metaplasia(P<0.05),while CDX2 was positively correlated with the expression of MUC2(P<0.05).Conclusion MEX3A is negatively correlated with gastric cancer and intestinal metaplasia differentiation.Gastric cancer is characterized by high MEX3A expression and low CDX2 and MUC2 expression.
2.Epidemiological characteristics of early-onset colorectal cancer: a prospective cohort study from a single center
Tian JIN ; Yingshuang ZHU ; Chengcheng LIU ; Xing XU ; Wei LU ; Qian XIAO ; Kefeng DING ; Shu ZHENG
Chinese Journal of Gastrointestinal Surgery 2024;27(5):457-463
Objective:To explore the differences in distribution of colorectal cancer-related risk factors between patients with early-onset colorectal cancer (EOCRC) and those with late-onset colorectal cancer (LOCRC) in a Chinese cohort, and to provide reference and guidance for the prevention, diagnosis, and treatment of EOCRC.Methods:Using data from the National Colorectal Cancer Cohort study cohort, 5377 patients with newly diagnosed colorectal cancer (CRC) attending the Department of Colorectal Surgery and Oncology of the Second Affiliated Hospital, Zhejiang University School of Medicine from June 2018 to February 2023 were included in the study cohort. Questionnaires capturing epidemiological features, including lifestyle and dietary habits, were administered. The patients were divided into two groups, the cut-off age being 50 years. Those aged ≥50 years were defined as having LOCRC and those aged <50 years as having EOCRC. Wilcoxon (continuous variates) or χ 2 tests (categorical variates) were performed to compare differences in epidemiological features. Results:A total of 3799 people who had completed the questionnaire were included in this study, 491 of whom had EOCRC and 3308 LOCRC. The response rate to the questionnaire was 70.7%. The median ages of patients in the EOCRC and LOCRC groups were 43 and 66 years, respectively. There was a higher proportion of female patients (48.5% [253/491] vs. 35.8% [1184/3308], χ 2=28.8, P<0.001) in the EOCRC than the LOCRC group. Patients with EOCRC and lower body mass index (medium 22.1 kg/m 2 vs. 22.9 kg/m 2, W=744 793, P=0.005) and lower proportion of abdominal obesity (87.2% [428/491] vs. 93.8% [3103/3308], χ 2=38.3, P<0.001). Patients with EORC significantly less commonly reported a history of hypertension (5.9% [29/491] vs. 41.6% [1375/3308], χ 2=231.8, P<0.001), diabetes (1.4% [7/491] vs. 14.4% [476/3308], χ 2=63.6, P<0.001) and cardiovascular and cerebrovascular diseases (0.8% [4/491] vs. 7.3% [241/3308], χ 2=28.6, P<0.001). However, the proportion of patients with a family history of CRC was significantly higher ( P<0.05) in the EOCRC group (10.2% [50/491] vs. 6.9% [227/3 308], χ 2=6.5, P=0.010]. In terms of lifestyle, patients with EOCRC had shorter sleep duration (median: 8.0 hours vs. 8.5 hours, W=578 989, P<0.001), and were less likely to participate in physical exercise (29.5% [145/491] vs. 38.7% [1281/3308] χ 2=15.0, P<0.001) or engage in physical work (65.2% [320/491] vs. 74.1% [2450/3308], χ 2=16.7, P<0.001). Meanwhile, in the EOCRC group a lower percentage of patients were smokers (29.3% [144/491] vs. 42.7% [1411/3308], χ 2=46.9, P<0.001) and they smoked less (median 17.6 pack/year vs. 30.0 pack/year,W=55 850, P<0.001). Fewer patients in the EOCRC group habitually drank alcohol (21.0% [103/491] vs. 38.0% [1257/3308], χ 2=57.5, P<0.001) or tea (17.5% [86/491] vs. 28.7% [948/3308], χ 2=26.2, P<0.001) than in the LOCRC group. Compared with the LOCRC group, patients with EOCRC had a higher frequency of intake of fresh meat, fresh fruit, eggs, and dairy products and a lower frequency of intake of preserved meat and pickled vegetables; these differences are statistically significant (all P<0.05). There was no statistically significant difference in consumption of fresh vegetables or a high-sugar diet between the two groups (both P>0.05). Conclusions:This study highlights disparities in adverse lifestyle and dietary habits between patients in China with EOCRC versus LOCRC.
3.Homing and characteristic analysis of macrophage in immune-mediated aplastic anemia model mice
Wei SUN ; Zenghua LIN ; Han WANG ; Hui JIA ; Laigen TONG ; Zhipeng ZHANG ; Wen LI ; Chengcheng ZHOU ; Hong LIU
Chinese Journal of Hematology 2024;45(6):594-598
To investigate the dynamic homing process and characteristics of macrophages in different organs of immune-mediated aplastic anemia (AA) model mice. Macrophages in donor lymph nodes were sorted by magnetic beads and labeled with PKH67. After modeling according to the preparation method of the AA model, peripheral blood rountine analysis, bone marrow biopsy and HE staining results were analyzed to verify the modeling effect. On days 4, 8, and 12 of modeling, the bone marrow, spleen, and lymph node mononuclear cells were collected, and dynamic changes of PKH67-labeled macrophages in donor mice were analyzed by flow cytometry. In this study, dynamic changes in PKH67-labeled macrophages in the pathogenesis of AA model mice were explored. Macrophages in donor mice homed to the lymph nodes, expanding and differentiating in the lymph nodes, and finally transported to the bone marrow and spleen. Through proteomics mass spectrometry analysis, the related immune inflammatory response pathway of macrophages involved in the activation of the AA bone marrow microenvironment was preliminarily revealed, which provides a basis for the pathological macrophages involved in the pathogenesis of AA model mice.
4.Epidemiological characteristics of early-onset colorectal cancer: a prospective cohort study from a single center
Tian JIN ; Yingshuang ZHU ; Chengcheng LIU ; Xing XU ; Wei LU ; Qian XIAO ; Kefeng DING ; Shu ZHENG
Chinese Journal of Gastrointestinal Surgery 2024;27(5):457-463
Objective:To explore the differences in distribution of colorectal cancer-related risk factors between patients with early-onset colorectal cancer (EOCRC) and those with late-onset colorectal cancer (LOCRC) in a Chinese cohort, and to provide reference and guidance for the prevention, diagnosis, and treatment of EOCRC.Methods:Using data from the National Colorectal Cancer Cohort study cohort, 5377 patients with newly diagnosed colorectal cancer (CRC) attending the Department of Colorectal Surgery and Oncology of the Second Affiliated Hospital, Zhejiang University School of Medicine from June 2018 to February 2023 were included in the study cohort. Questionnaires capturing epidemiological features, including lifestyle and dietary habits, were administered. The patients were divided into two groups, the cut-off age being 50 years. Those aged ≥50 years were defined as having LOCRC and those aged <50 years as having EOCRC. Wilcoxon (continuous variates) or χ 2 tests (categorical variates) were performed to compare differences in epidemiological features. Results:A total of 3799 people who had completed the questionnaire were included in this study, 491 of whom had EOCRC and 3308 LOCRC. The response rate to the questionnaire was 70.7%. The median ages of patients in the EOCRC and LOCRC groups were 43 and 66 years, respectively. There was a higher proportion of female patients (48.5% [253/491] vs. 35.8% [1184/3308], χ 2=28.8, P<0.001) in the EOCRC than the LOCRC group. Patients with EOCRC and lower body mass index (medium 22.1 kg/m 2 vs. 22.9 kg/m 2, W=744 793, P=0.005) and lower proportion of abdominal obesity (87.2% [428/491] vs. 93.8% [3103/3308], χ 2=38.3, P<0.001). Patients with EORC significantly less commonly reported a history of hypertension (5.9% [29/491] vs. 41.6% [1375/3308], χ 2=231.8, P<0.001), diabetes (1.4% [7/491] vs. 14.4% [476/3308], χ 2=63.6, P<0.001) and cardiovascular and cerebrovascular diseases (0.8% [4/491] vs. 7.3% [241/3308], χ 2=28.6, P<0.001). However, the proportion of patients with a family history of CRC was significantly higher ( P<0.05) in the EOCRC group (10.2% [50/491] vs. 6.9% [227/3 308], χ 2=6.5, P=0.010]. In terms of lifestyle, patients with EOCRC had shorter sleep duration (median: 8.0 hours vs. 8.5 hours, W=578 989, P<0.001), and were less likely to participate in physical exercise (29.5% [145/491] vs. 38.7% [1281/3308] χ 2=15.0, P<0.001) or engage in physical work (65.2% [320/491] vs. 74.1% [2450/3308], χ 2=16.7, P<0.001). Meanwhile, in the EOCRC group a lower percentage of patients were smokers (29.3% [144/491] vs. 42.7% [1411/3308], χ 2=46.9, P<0.001) and they smoked less (median 17.6 pack/year vs. 30.0 pack/year,W=55 850, P<0.001). Fewer patients in the EOCRC group habitually drank alcohol (21.0% [103/491] vs. 38.0% [1257/3308], χ 2=57.5, P<0.001) or tea (17.5% [86/491] vs. 28.7% [948/3308], χ 2=26.2, P<0.001) than in the LOCRC group. Compared with the LOCRC group, patients with EOCRC had a higher frequency of intake of fresh meat, fresh fruit, eggs, and dairy products and a lower frequency of intake of preserved meat and pickled vegetables; these differences are statistically significant (all P<0.05). There was no statistically significant difference in consumption of fresh vegetables or a high-sugar diet between the two groups (both P>0.05). Conclusions:This study highlights disparities in adverse lifestyle and dietary habits between patients in China with EOCRC versus LOCRC.
5.Summary of the best evidence for external auditory canal irrigation in patients with cerumen embolism
Ruya YUAN ; Wei XU ; Xiaolu YANG ; Yanling DENG ; Xiaochang HUANG ; Xiaofen LI ; Chengcheng LIU ; Lijing HU
Chinese Journal of Modern Nursing 2024;30(31):4234-4240
Objective:To summarize the best evidence for external auditory canal irrigation in patients with cerumen embolism.Methods:The clinical decisions, guidelines, systematic reviews, expert consensus, group standards, evidence summaries, and randomized controlled trials regarding external auditory canal irrigation in patients with cerumen embolism were retrieved from databases and websites such as BMJ Best Practice, UpToDate, Guidelines International Network, National Institute for Health and Clinical Excellence, Joanna Briggs Institute Evidence-Based Health Care Center Database, PubMed, Embase, China National Knowledge Infrastructure, WanFang data, and China Biology Medicine disc. The search period was from database establishment to February 15, 2023. Six researchers screened the literature, evaluated the methodological quality, and extracted and summarized the best evidence for external auditory canal irrigation in patients with cerumen embolism.Results:A total of nine articles were included, including one clinical decision, two guidelines, two systematic reviews, one group standard, and three randomized controlled trials. Sixteen pieces of evidence were summarized from six aspects of operators: pre-operation evaluation and preparation, operation process, post-operation handling, health education, and adverse reactions during operation.Conclusions:This paper summarizes the best evidence for external auditory canal irrigation in patients with cerumen embolism. Medical and nursing staff should carefully select and apply evidence based on clinical scenarios and patient's wishes.
6.Efficacy analysis of precise and empirical bismuth-containing quadruple therapy guided by clarithromycin sensitivity testing in the first eradication of Helicobacter pylori in Ningxia
Chengcheng FENG ; Linke MA ; Jun LIU ; Xue LI ; Xiaoming SU ; Yuanyuan TANG ; Xiaofei LI ; Yanling LI ; Qiang WEI ; Zhanbin HOU ; Xilong ZHANG ; Shengjuan HU
Chinese Journal of Digestion 2024;44(5):302-307
Objective:To explore the efficacy of precise and empirical bismuth-containing quadruple therapy guided by clarithromycin sensitivity testing in the first eradication of Helicobacter pylori ( H. pylori) in Ningxia. Methods:From August 12, 2022 to March 22, 2023, 600 patients diagnosed as H. pylori-positive by 14C-urea breath test ( 14C-UBT) for the first time in People′s Hospital of Ningxia Hui Autonomous Region, Ningnan Hospital of People′s Hospital of Ningxia Hui Autonomous Region, Zhongwei People′s Hospital, Yanchi County People′s Hospital, and Pingluo People′s Hospital were selected, and divided into empirical treatment group (hereinafter referred to as the empirical group), genetic testing group (hereinafter referred to as the genetic group), and drug sensitivity testing group (hereinafter referred to as the drug sensitivity group) by using random number table with 200 patients in each group. The empirical group did not undergo drug sensitivity testing and genetic testing, while the genetic and drug sensitivity groups were confirmed to be sensitive to clarithromycin through genetic testing and drug sensitivity testing, and the patients with drug-resistant were excluded, respectively. All the patients of the 3 groups received the same clarithromycin bismuth-containing quadruple therapy. Intention-to-treat (ITT) and per-protocol (PP) analyses were performed to compare the eradication rates of H. pylori among 3 groups. Cost-effectiveness ratio (CER) and incremental cost-effectiveness ratio (ICER) were used for cost-effectiveness and sensitivity analysis based on the ITT. Chi-square test was used for statistical analysis. Results:There were 200, 126, and 168 patients included in the empirical group, genetic group, and drug sensitivity group in ITT analysis, and 190, 123, and 164 patients were enrolled in the 3 groups in PP analysis, respectively. The results of ITT analysis showed that the eradication rates of H. pylori in the empirical group, genetic group, and drug sensitivity group were 80.5% (161/200), 94.4% (119/126), and 95.2% (160/168), respectively. The results of PP analysis indicated that the eradication rates of H. pylori in the 3 groups were 84.7% (161/190), 96.7% (119/123), and 97.6% (160/164), respectively, and the differences were statistically significant ( χ2=25.39 and 24.93, both P<0.001). The H. pylori eradication rates of genetic group and drug sensitivity group were both higher than that of empirical group in ITT and PP analysis( χ2=12.40, 17.80, 11.42, and 17.13; all P<0.001). The cost-effectiveness analysis showed that the direct treatment cost of the empirical group, genetic group, and drug sensitivity group was 400.8, 729.2, and 779.2 yuan, respectively, and the CER was 4.98, 7.72, and 8.18 yuan/%, respectively. Compared to the empirical group, the ICER of the genetic group and drug sensitivity group was 23.6 and 25.7 yuan/%, respectively. The sensitivity analysis demonstrated that, when the cost of genetic testing reduced or increased by 20%, the ICER of the genetic group compared to the empirical group was 21.8 or 25.5 yuan/%, respectively. When the cost of drug sensitivity testing reduced or increased by 20%, the ICER of the drug sensitivity group compared to the empirical group was 23.3 or 28.2 yuan/%. When the cost of gastroscopy reduced or increased by 20%, the ICER of the genetic group compared to the empirical group was 20.8 or 26.5 yuan/%, and the ICER of the drug sensitivity group compared to the empirical group was 23.0 or 28.4 yuan/%, respectively. Conclusion:In Ningxia, if the clarithromycin bismuth-containing quadruple regimen is applied as the first H. pylori eradication regimen, in order to achieve the clinical eradication efficacy of H. pylori, and the patients can accept an additional payment of 23.6 or 25.7 yuan for each 1% increasing in the H. pylori eradication rate, then the precision treatment after clarithromycin resistance test is recommended.
7.Clinical study of Yin-Yang balancing acupuncture plus Tuina in the treatment of post-stroke depression
Lanzhu LI ; Xin CHEN ; Chengcheng GE ; Qinghua YE ; Wei FAN ; Jianhao LIU ; Fuqing ZHANG
Journal of Acupuncture and Tuina Science 2024;22(3):214-222
Objective:To observe the clinical efficacy of Yin-Yang balancing acupuncture plus Tuina(Chinese therapeutic massage)for post-stroke depression(PSD). Methods:A total of 72 PSD patients were randomized into an acupuncture-Tuina group and a Western medicine group using the random number table method,with 36 cases in each group.The Western medicine group was treated with fluoxetine hydrochloride capsules.The acupuncture-Tuina group was treated with Yin-Yang balancing acupuncture plus Tuina therapy.Both groups were treated for 4 weeks.After treatment,the clinical efficacy was compared,and the changes in Hamilton depression scale(HAMD)score,National Institute of Health stroke scale(NIHSS)score,serum neurotransmitter levels,and electroencephalogram(EEG)were observed. Results:The total effective rate of the Western medicine group and the acupuncture-Tuina group was 83.3%and 94.4%,respectively.There was a significant difference in the total effective rate between the two groups(P<0.05).After treatment,the serum levels of 5-hydroxytryptamine(5-HT),norepinephrine(NE),and dopamine(DA)were higher than those in the same group before treatment,and the intra-group differences were all statistically significant(P<0.05).The serum levels of 5-HT,NE,and DA in the acupuncture-Tuina group were higher than those in the Western medicine group,and the differences between the groups were statistically significant(P<0.05).After treatment,the scores of HAMD and NIHSS in both groups decreased,and the intra-group differences were statistically significant(P<0.05).The scores in the acupuncture-Tuina group were lower than those in the Western medicine group,and the differences between the two groups were all statistically significant(P<0.05).After treatment,the EEG diffuse wave[(delta+theta)/(alpha+beta)]ratio(DTABR)and delta/beta ratio(DBR)in both groups decreased,and the intra-group differences were statistically significant(P<0.05).The ratios in the acupuncture-Tuina group were lower than those in the Western medicine group,and the differences between the two groups were statistically significant(P<0.05). Conclusion:Yin-Yang balancing acupuncture plus Tuina therapy has a better efficacy than oral fluoxetine hydrochloride capsules in the treatment of PSD,which can increase the levels of serum 5-HT,DA,and NE,and regulate brain waves.
8.The mediating effect of self-regulation fatigue between acceptance of hearing impairment and work withdrawal behavior in young and middle-aged patients with sudden deafness
Mengjie LI ; Linyan GUO ; Wei GAO ; Chen DONG ; Yan DONG ; Chengcheng LIU
Chinese Journal of Practical Nursing 2023;39(9):691-698
Objective:To explore the mediating effect of self-regulation fatigue between acceptance of hearing impairment and work withdrawal behavior in young and middle-aged patients with sudden deafness, so as to provide reference for the formulation of intervention measures for job withdrawal behavior.Methods:A cross-sectional survey was conducted to facilitate the selection of 326 young and middle-aged patients with sudden deafness who were treated in the Department of Otolaryngology, Head and Neck Surgery in the First Affiliated Hospital and the Second Affiliated Hospital of Air Force Military Medical University of the Chinese PLA from February 2021 to January 2022. The survey was carried out by general information questionnaire, the Revised Acceptance Disability Scale, the Self-Regulatory Fatigue Scale, and the Work Withdrawal Behavior Scale. Structural equation model method was used to analyze the mediating effect.Results:The acceptance of hearing impairment score in young and middle-aged patients with sudden deafness was (59.82 ± 10.99) points, the self-regulation fatigue score was (60.38 ± 8.84) points, and the work withdrawal behavior score was (39.06 ± 6.51) points. Self-regulation fatigue was negatively correlated with acceptance of hearing impairment ( r=-0.541, P<0.01). Work withdrawal behavior was negatively correlated with acceptance of hearing impairment ( r=-0.488, P<0.01), and was positively correlated with self-regulation fatigue ( r=0.587, P<0.01). Self-regulation fatigue played a partial mediating effect between the acceptance of hearing impairment and work withdrawal in young and middle-aged patients with sudden deafness, and the mediating effect ratio was 56.30%. Conclusions:The acceptance of hearing impairment can not only directly affect the work withdrawal behavior of young and middle-aged patients with sudden deafness, but also indirectly affect their work withdrawal behavior through self-regulation fatigue. Medical staff should pay attention to the internal relationship between the acceptance of hearing impairment, self-regulation fatigue and work withdrawal behaviors, so as to improve the acceptance of hearing impairment of patients, relieve their self-regulation fatigue, and avoid the occurrence of work withdrawal behaviors.
9.Molecular Mechanism of Prepared Radix Polygoni Multiflori in Treatment of Non-alcoholic Fatty Liver Disease Based on Network Pharmacology and Animal Experiments
Huiru YANG ; Changyudong HUANG ; Liying ZHU ; Chengcheng LI ; Yongjie XU ; Xing LI ; Wei PAN ; Zulong ZHANG
World Science and Technology-Modernization of Traditional Chinese Medicine 2023;25(11):3678-3691
Objective To explore and validate the mechanism of Prepared Radix Polygoni Multiflori in the treatment of NAFLD based on network pharmacology and animal non-alcoholic fatty liver disease(NAFLD)model experiments.Methods Consult the literature to compare the differences between Radix Polygoni Multiflori and Prepared Radix Polygoni Multiflori(PRPM).Herb database and SwissADME database were used to screen the active ingredients of Prepared Radix Polygoni Multiflori,SwissTargetPrediction database was used to predict its targets,OMIM,DISGENET and GEENCARDS databases were used to screen the NAFLD-related targets,conduct GO functional enrichment analysis and KEGG pathway enrichment analysis.The active ingredient-target-KEGG signaling pathway-NAFLD network was mapped later.The mice with NAFLD were treated with Prepared Radix Polygoni Multiflori by gavage for 8 weeks;serum triglyceride level and alanine aminotransferase(ALT)activity were measured;the liver lesions were observed by HE staining;the potential mechanism of action of Radix Polygoni Multiflori in the treatment of NAFLD was verified by Western blot.Results The differences between Radix Polygoni Multiflori and PRPM were consulted.Six pharmacological components and 32 potential action targets of Radix Polygoni Multiflori for the treatment of NAFLD were screened by network pharmacology,GO and KEGG pathways were enriched to lipid and atherosclerosis-related pathways,AMPK signaling pathway,etc.;HE staining verified that Prepared Radix Polygoni Multiflori has the function of improving NAFLD and is associated with the alteration of FASN,ACC,SCD protein of AMPK signaling pathway.Conclusion Radix Polygoni Multiflori has the potential to improve NAFLD by regulating FASN,ACC and SCD.
10.Radiation protection testing and radiation shielding performance evaluation for a novel self-shielding radiotherapy system
Xiangjie MA ; Mingsheng LI ; Quanfu SUN ; Chengcheng WANG ; Xiao WEI ; Jinsheng CHENG
Chinese Journal of Radiological Medicine and Protection 2023;43(11):906-912
Objective:To evaluate the radiation shielding performance for a novel self-shielded ZAP-X radiotherapy system used for intra-cranial and neck treatments. The present evaluation was performed according to the relevant Chinese national standards and the clinical placement of the radiotherapy system in an unshielded treatment room.Methods:The radiation source of the ZAP-X was a 3 MV linear accelerator. A total of 33 detection sites were selected surrounding the self-shielded system at 1.3, 2.3 and 3.3 m away from the periphery of the equipment. The maximum ambient dose equivalent rate in each irradiation condition was measured accordingly. A commonly used clinical treatment plan was selected to simulate the treatment process. During the delivery of this treatment plan, the cumulative doses of these 33 sites were measured, separately. The applicable current radiation protection standard for radiotherapy in China was chosen to evaluate the radiation shielding performance of the system.Results:According to the measurement result of the ambient dose equivalent rates along the aforementioned perimeter lines, a suggestion was put forward to redefine the existing 1 m controlled area by determining the distance at which the instantaneous dose rate of 10 μSv/h will not be exceeded. This is to meet the requirements of the Chinese standard GBZ 121-2020.Conclusions:According to the existing Chinese national radiation protection standards, the self-shielded radiotherapy system in the unshielded treatment room has the clinical applicability in China. But for such a novel self-shielded system, the corresponding performance testing and radiation protection standards shall be formulated.

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