Objective:To explore the clinical efficacy and safety of a multimodal treatment regimen integrating radiotherapy, chemotherapy, and immunotherapy in patients with human epidermal growth factor receptor 2 (HER2) -negative locally advanced or advanced gastric cancer.Methods:A total of 34 patients with unresectable, HER2-negative, locally advanced or metastatic gastric/gastroesophageal junction (G/GEJ) adenocarcinoma admitted to the Affiliated Cancer Hospital of Guizhou Medical University from September 2021 to March 2024 were selected as study objects. Participants received one cycle of either XELOX regimen (capecitabine + oxaliplatin) or SOX regimen (S-1 + oxaliplatin) with immunotherapy (sintilimab or nivolumab) . The process was succeeded by radiotherapy targeted at the primary G/GEJ tumor and regional lymph nodes. In selected cases, sequential radiotherapy was also administered for distant metastases. The primary endpoint was objective response rate (ORR) , and secondary endpoints were disease control rate (DCR) , clinical symptom response, changes in Karnofsky performance status (KPS) score, progression-free survival (PFS) , and adverse reactions. Clinical efficacy was assessed in accordance with Response Evaluation Criteria in Solid Tumors version 1.1. Adverse reactions were assessed and graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events version 5.0 and the Chinese Society of Clinical Oncology guidelines for management of immune checkpoint inhibitor-related toxicity. With a median follow-up of 7 months (range: 2.3 to 30 months) , the final evaluation considered the best response documented throughout follow-up. Survival curves were constructed utilizing Kaplan-Meier analysis.Results:By the end of follow-up, an overall ORR of 58.8% (20/34) and DCR of 70.6% (24/34) were observed. The ORR of lesions by radiotherapy reached 73.8% (48/65) and the DCR reached 92.3% (60/65) . Univariate analysis showed that the ORR of female patients (84.6%, 11/13) was higher than that of male patients (42.9%, 9/21) , and the ORR of patients with distant lymph node metastasis alone (83.3%, 15/18) was higher than that of patients with distant lymph node metastasis combined with organ metastasis or organ metastasis alone (18.2%, 2/11) , with statistically significant differences ( P=0.030; P=0.010) . There were no statistically significant differences in ORR among patients with different age ( P=0.487) , KPS score ( P=0.198) , primary tumor location ( P=0.280) , histological differentiation ( P=0.668) , chemotherapy regimen ( P=0.728) , or immunotherapy regimen ( P>0.999) . Twenty-two of 23 (95.7%) patients with upper abdominal pain were relieved, 10 of 21 (47.6%) patients with appetite loss were relieved, 15 of 17 patients with upper abdominal distension were relieved, 13 of 14 patients with melena were relieved, 6 of 7 patients with eating obstruction were relieved, 3 of 4 patients with metastatic site pain were relieved, and 2 patients with hematemesis were relieved. KPS score enhanced in 82.4% (28/34) of patients, remained stable in 11.8% (4/34) , and declined in 5.8% (2/34) . The median PFS of the 34 patients was 7.9 months. The most common adverse reactions during radiotherapy combined with chemotherapy and immunotherapy were hematological adverse reactions, in which neutropenia accounted for the highest proportion (91.2%, 31/34) , followed by anemia (50.0%, 17/34) . Fatigue was the most common non-hematological adverse reaction (50.0%, 17/34) , followed by nausea and vomiting (26.5%, 9/34) . The adverse reactions of 6 patients receiving immune monotherapy maintenance were anemia, hypothyroidism, transaminase elevation, proteinuria, fatigue, and rash, all of which were grade 1-2. Conclusions:Radiotherapy combined with chemotherapy and immunotherapy shows good short-term clinical efficacy in patients with HER2-negative locally advanced or advanced gastric cancer, and the overall adverse reactions are tolerable. Female or patients with distant lymph node metastasis alone may be the preferred population for this study protocol.

Objective:To investigate the effect of abdominal circumference on intestinal radiation dose volume and acute intestinal toxicity in pelvic intensity modulated radiation therapy for rectal cancer.Methods:A total of 150 patients with locally advanced rectal cancer (LARC) who received adjuvant and neoadjuvant concurrent chemoradiotherapy at the Affiliated Cancer Hospital of Guizhou Medical University from March 2023 to January 2025 were enrolled, including 82 cases of adjuvant radiotherapy and 68 cases of neoadjuvant radiotherapy. All patients underwent radiotherapy CT simulation positioning in the standard mode of prone position with abdominal board padding and bladder filling. Intestinal toxicity was categorized as a binary variable based on the occurrence of ≥2 grade acute intestinal toxicity. Linear and logistic regression models were used to analyze the factors influencing intestinal radiation dose volumes (V 10, V 20, V 30, V 40) and acute intestinal toxicity in LARC patients. Generalized additive models and piecewise linear and logistic regression analyses were employed to examine the threshold effects of abdominal circumference on intestinal radiation dose volumes and acute intestinal toxicity. The threshold value for abdominal circumference was determined based on the upper limit of the 95% CI for the threshold. A difference test was used to validate the differences in intestinal radiation dose volume and acute intestinal toxicity between small and medium-to-large abdominal circumferences. Results:Univariate analysis showed that, gender, body mass, abdominal circumference, planning target volume (PTV), intestinal volume were all influencing factors for the radiation dose volumes (V 10, V 20, V 30, V 40) of each intestinal segment of patients with LARC undergoing adjuvant radiotherapy (all P<0.05). Body mass, abdominal circumference, intestinal volume were all influencing factors for the radiation dose volumes (V 10, V 20, V 30, V 40) of each intestinal segment of patients with LARC undergoing neoadjuvant radiotherapy (all P<0.05). Body mass index (BMI), abdominal circumference, intestinal volume and individual intestinal radiation volumes (V 10, V 20, V 30, V 40) were all influencing factors for the acute intestinal toxicity of patients with LARC undergoing adjuvant radiotherapy (all P<0.05). Body mass, BMI, abdominal circumference, multiple intestinal radiation dose volumes (V 20, V 30, V 40) were all influencing factors for the acute intestinal toxicity of patients with LARC undergoing neoadjuvant radiotherapy (all P<0.05). Multivariate analysis showed that, abdominal circumference (V 10: β=-1.01, 95% CI: -1.68--0.33, P=0.004; V 20: β=-0.94, 95% CI: -1.28--0.60, P<0.001; V 30: β=-0.58, 95% CI: -0.82--0.34, P<0.001; V 40: β=-0.41, 95% CI: -0.60--0.23, P<0.001) was an independent influencing factor for the radiation dose volume of each intestinal segment of patients with LARC undergoing adjuvant radiotherapy. Abdominal circumference (V 10: β=-0.92, 95% CI: -1.62--0.22, P=0.010; V 20: β=-0.84, 95% CI: -1.11--0.57, P<0.001; V 30: β=-0.42, 95% CI: -0.57--0.28, P<0.001; V 40: β=-0.30, 95% CI: -0.41--0.19, P<0.001) was an independent influencing factor for the radiation dose volume of each intestinal segment of patients with LARC undergoing neoadjuvant radiotherapy. Abdominal circumference ( OR=0.86, 95% CI: 0.78-0.95, P=0.002) was an independent influencing factor for the acute intestinal toxicity of patients with LARC undergoing adjuvant radiotherapy. Abdominal circumference ( OR=0.87, 95% CI: 0.79-0.96, P=0.004) was an independent influencing factor for the acute intestinal toxicity of patients with LARC undergoing neoadjuvant radiotherapy. The generalized additive model revealed a nonlinear relationship between abdominal circumference and intestinal radiation dose volume and acute intestinal toxicity of adjuvant radiotherapy patients. Further segmented regression analysis results showed that there was a threshold effect between abdominal circumference and intestinal radiation dose volume (V 10, V 20, V 30, V 40) and acute intestinal toxicity. The inflection point values between abdominal circumference and intestinal radiation dose volume V 10, V 20, V 30, V 40 in LARC patients undergoing adjuvant radiotherapy were all 71.9 cm; the inflection point values between abdominal circumference and the intestinal radiation dose volume V 10, V 20, V 30, V 40 in LARC patients undergoing neoadjuvant radiotherapy were 69.0, 69.0, 69.0, 68.6 cm, respectively; The inflection point values between abdominal circumference and acute intestinal toxicity in LARC patients undergoing adjuvant radiotherapy and neoadjuvant radiotherapy were 71.9, 69.0 cm, respectively. Based on the upper limit of the 95% CI threshold, the cutoff values for small and medium-to-large abdominal circumferences for patients undergoing adjuvant and neoadjuvant radiotherapy were set at 76.1, 71.9 cm, respectively. In patients undergoing adjuvant radiotherapy, the levels of intestinal radiation dose volume V 10 [ (7.65±2.29) cm 3vs. (5.88±2.68) cm 3, t=2.76, P=0.007], V 20 [ (4.28±1.27) cm 3vs. (2.72±1.31) cm 3, t=4.81, P<0.001], V 30 [ (2.42±1.07) cm 3vs. (1.37±0.76) cm 3, t=4.95, P<0.001], V 40 [ (1.69±0.74) cm 3vs. (0.92±0.58) cm 3, t=4.93, P<0.001] in the small abdominal circumference group ( n=22) were significantly higher than those in patients with medium-to-large abdominal circumferences ( n=60) ; In patients undergoing neoadjuvant radiotherapy, patients with small abdominal circumferences ( n=11) had significantly higher V 20 [ (3.09±0.84) cm 3vs. (2.28±1.17) cm 3, t=2.17, P=0.033], V 30 [1.44 (1.22, 1.53) cm 3vs. 0.91 (0.56, 1.22) cm 3, Z=-3.04, P=0.002], V 40 [0.93 (0.84, 1.09) cm 3vs. 0.44 (0.30, 0.81) cm 3, Z=-3.19, P=0.001] than patients with medium-to-large abdominal circumferences ( n=57). In patients receiving adjuvant radiotherapy and neoadjuvant radiotherapy, there were statistically significant differences in acute intestinal toxicity between patients with small abdominal circumferences and with medium-to-large abdominal circumferences ( χ2=10.46, P=0.001; χ2=8.13, P=0.004) . Conclusions:In the standard mode (prone position with abdominal board padding and bladder filling), abdominal circumference is an independent factor influencing the intestinal radiation dose volume and acute intestinal toxicity in rectal cancer radiotherapy patients. There is a significant non-linear threshold effect between abdominal circumference and different levels of intestinal radiation dose volume and acute intestinal toxicity. The impact of abdominal circumference on intestinal radiation dose volume and toxicity differs significantly before and after the inflection point value. Patients with smaller abdominal circumferences not only fail to achieve the expected benefits under the current standard radiotherapy regimen but also face higher risks of intestinal radiation dose volume and toxicity.

BACKGROUND:The research of dental stem cells in the fields of regenerative medicine and tissue engineering has been deepening,bringing hope for the repair of tooth-related tissues and the treatment of systemic diseases.However,there is a lack of systematic research and analysis on the biological characteristics of dental stem cells in different age groups. OBJECTIVE:To explore the biological characteristics of the human deciduous tooth and permanent tooth pulp stem cells cultured in umbilical cord blood platelet lysate to provide a reliable basis for human platelet lysates to replace fetal bovine serum. METHODS:The pulp tissues of deciduous teeth,juvenile permanent teeth and adult permanent teeth were taken out and cultured in DMEM/F-12 medium supplemented with 10%fetal bovine serum or different concentrations(5%,10%and 15%)of human platelet lysates.Cell proliferation in the four groups was detected by cytometry.The optimal concentration of human platelet lysates was selected for subsequent experiments.Under the optimal concentration of human platelet lysates,human deciduous tooth and juvenile and adult permanent tooth pulp stem cells were cultured in vitro.The cell growth status was observed under the microscope.The specific antigen on the cell surface was detected by flow cytometry.The cell proliferation ability was tested by the cell counting method and CCK-8 assay.The cell differentiation ability in vitro was observed by a three-line differentiation assay. RESULTS AND CONCLUSION:(1)The cell proliferation rate of the 10%human platelet lysate group was the highest.(2)In all three groups,fusiform fibrous cells grew and expanded from around the tissue block.There was no significant difference between deciduous teeth and juvenile permanent tooth cells,but the adult permanent tooth cells were larger than the deciduous and juvenile permanent tooth cells of the same generation.(3)The results of flow cytometry showed that deciduous teeth,juvenile permanent teeth and adult permanent teeth conformed to the phenotypic characteristics of mesenchymal stem cells.(4)The proliferative capacity of adult permanent dental pulp stem cells was significantly lower than those of deciduous teeth and juvenile permanent dental pulp stem cells(P<0.01).(5)mRNA expressions of osteoblast-related genes alkaline phosphatase and bone morphogenetic protein 2,lipoprotein lipase and peroxisome proliferator-activated receptor γ2,mRNA expressions of chondroblast related gene type II collagen α1 and cartilage oligomeric matrix protein in adult pulp stem cells of permanent teeth were significantly lower than those of deciduous teeth and juvenile permanent teeth pulp stem cells(P<0.01).(6)Compared with adult dental pulp stem cells,human deciduous teeth and juvenile permanent teeth dental pulp stem cells have the stronger proliferative capacity and multidirectional differentiation potential,and are more suitable for clinical research and disease treatment.

Objective To compare the value of TACE+microwave ablation(MWA)+programmed death-1(PD-1)and TACE+MWA for treating primary hepatic carcinoma(PHC).Methods Data of 80 PHC patients who underwent TACE+MWA+PD-1(observe group)or TACE+MWA treatment(control group)were retrospectively analyzed(each n=40).The baseline data,therapeutic efficacy of PHC and complications were compared between groups.Results No significant difference of baseline data was found between groups(all P＞0.05).The objective response rate(ORR)of observe group and control group was 90.00％and 72.50％,respectively,while the disease control rate(DCR)was 97.50％and 95.00％,respectively,with no significant difference between groups(both P＞0.05).The median overall survival(OS)of observe group and control group was 30.80 months and 15.70 months,respectively,while the median progression free survival(PFS)was 23.35 months and 6.80 months,respectively.OS and PFS of observe group were both longer than those of control group(both P＜0.05).No significant difference of the incidence of complications was detected between groups(all P＞0.05),and all were improved after symptomatic treatment.Conclusion TACE+MWA+PD-1 was superior to TACE+MWA for treating PHC.

OBJECTIVE: To verify the effect of Buyang Huanwu Decoction (BHD) in ameliorating erectile dysfunction (ED) after radical prostatectomy (RP). METHODS: The composition of BHD was verified by ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS/MS) analysis. Bilateral cavernous nerve crush injury (BCNI) in rats was used to mimic the neurovascular injury occurring after RP. By the envelope method, forty rats were randomly divided into 4 groups as follows: sham (cavernous nerves exposed only), model (BCNI), low-dosage BHD [LBHD, 12.8 g/(kg·d)], and high-dosage BHD [HBHD, 51.2 g/(kg·d)] groups, 10 rats in each group, feeding for 3 weeks respectively. Erectile function was evaluated by measuring intracavernosal pressure (ICP). Changes in the histopathology of corpus cavernosum (CC) were examined by hematoxylin-eosin staining. Meanwhile, the fibrosis of CC was measured by Masson's trichrome staining and Western blot was used to detect the expressions of collagen I, transforming growth factor beta 1 (TGF- β 1) and α-smooth muscle actin (α-SMA). Apoptosis index was detected by terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL) and Western blot for determining the expressions of B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X (Bax). The oxidative stress in the CC were assessed by the superoxide dismutase (SOD), malondialdehyde (MDA) and reactive oxygen species (ROS) levels. The proteins expression of c-Jun N-terminal kinase (JNK) and c-Jun were detected by Western blot. In addition, the expression of α-SMA and p-c-Jun in the CC was observed by double immunofluorescence staining. RESULTS: The UPLC-QTOF-MS/MS analysis showed that BHD contained calycosin-7-O- β -D-glucoside, ononin, calycosin and formononetin. Compared with the model group, LBHD and HBHD treatment improved the ICP and the circumference, area, and weight of CC (P<0.05 or P<0.01). Furthermore, LBHD and HBHD treatments increased CC smooth muscle content and decreased apoptosis index (P<0.05 or P<0.01). LBHD and HBHD also elevated SOD and expression level of α -SMA and Bcl-2, and reduced MDA and ROS levels, as well as expression of TGF- β 1, collagen I, Bax, p-c-JNK, p-JNK in the CC compared with the model group (P<0.05 or P<0.01). The double immunofluorescence staining showed that the fluorescence degree of p-c-Jun in both LBHD and HBHD treatment groups was significantly reduced, whereas the α -SMA expression increased (P<0.05 or P<0.01). CONCLUSIONS BHD can improve ED of rats with BCNI, which is related to inhibiting fibrosis, apoptosis, and oxidative stress of CC. The ROS/JNK/c-Jun signaling pathway may play an important role in the process.
Male ; Humans ; Rats ; Animals ; Reactive Oxygen Species ; Tandem Mass Spectrometry ; bcl-2-Associated X Protein ; Rats, Sprague-Dawley ; Erectile Dysfunction/drug therapy* ; Collagen ; Fibrosis ; Disease Models, Animal

Objective:To analyze the correlation between the volume of irradiated pelvic bone marrow and acute hematologic toxicity (HT), in order to provide clinical data to reduce the risk of acute HT and optimize the radiotherapy plan.Methods:From October 2017 to May 2019, 41 LARC patients who received neoadjuvant concurrent chemoradiotherapy (CCRT) were retrospectively reviewed in our center. All patients were treated with 5-field intensity-modulated radiotherapy (IMRT), and the prescription dose delivered to PTV was 45-50.4 Gy in 25-28 fractions. Capecitabine or 5-fluorouracil (5-FU) wasadministered daily 5 days a week during radiotherapy. Different HTswere recorded according to National Cancer Institute Common Toxicity Criteria Version 5.0 (NCI-CTC.V5.0) based on laboratory tests. The volume of PBM or each site (coxal, sacrum, femoral) receiving more than x Gy refers to as TVx, CVx, SVx, and FVx, respectively. Logistic regression was performed to evaluate the association between the volume of irradiated pelvic bone marrow and different HT. Generalized additive model (GAM) and piecewise regression were used to further analyze the possible nonlinear relationship and threshold effect between them. Results:Multivariate logistic regression analysis showed that low-dose of irradiated total pelvic bone marrow volume ( TV5) and coxal bone marrow volume ( CV5, CV10) were significantly correlated with Grade ≥2 leukopenia( P<0.05). There was a significant negative correlation between the sacrum bone marrow volume ( SV5, SV10) and Grade ≥2 leukopenia ( P<0.05). A thresholdeffect has been observed between CV10 and Grade ≥2 leukopenia by Generalized additive model (GAM) and piecewise linear regression. The threshold between CV10 and Grade ≥2 leukopenia was 575 ml, OR (95% CI) was 1.85 (1.08, 3.16). Conclusions:In neoadjuvant IMRT of rectal cancer, CV is a better predictor of acute HT induced by CCRT than TV. The irradiated volume of CV associated with acute HT was mainly low-dose levels ( CV5, CV10). The thresholds of our study ( CV10= 575 ml) could be a good reference for the optimization of the radiotherapy plan.

Objective To comparatively observe the efficacy and safety of TACE combined with 125I seeds implantation or lenvatinib for treating hepatocellular carcinoma(HCC)complicated with portal vein tumor thrombosis(PVTT).Methods Totally 52 HCC patients complicated with type Ⅱ or type Ⅲ PVTT were enrolled and divided into TACE combined with 125I seeds group(group A,n=27)and TACE combined with lenvatinib group(group B,n=25).Objective response rate(ORR),overall survival(OS)and incidence rate of adverse reaction were compared between groups.Results ORR,the median OS,median OS of type Ⅱ PVTT and median OS of type Ⅲ PVTT was 70.37%(19/27),13.6 months,14.1 months and 13.2 months in group A,and 32.00%(8/25),11.3 months,12.3 months and 10.4 months in group B,respectively.The above indexes in group A were all better than those in group B(all P＜0.05).In group A,the incidence rate of adverse reaction was 48.15%(13/27),and no serious complication occurred.In group B,the incidence rate of adverse reaction was 88.00%(22/25),and severe drug toxicity was noticed in 5 cases(5/25,20.00%).Conclusion The efficacy and safety of TACE combined with 125I seeds were both better than those of TACE combined with lenvatinib for treating HCC complicated with PVTT.

Objective:To analyze the clinical characteristics of adult Chinese patients with syncope.Methods:This is a cross-sectional survey study. Patients with preliminary diagnosis of syncope in the Emergency Department, Geriatrics and Cardiology Outpatient Department, or Syncope Unit of 37 hospitals in 19 provinces, autonomous regions and the Hong Kong Special Administrative Region from June 2018 to March 2021 were included in this study. The clinical features of these patients with syncope were analyzed.Results:A total of 4 950 consecutive patients with syncope were included in this study. The age was (56.3±16.8)years, and 2 604 cases (52.6%) were male. The most common type of syncope was neurally mediated syncope (2 345 (47.4%)), followed by cardiac syncope (1 085 (21.9%)), orthostatic hypotensive syncope (311 (6.3%)), and unexplained syncope accounted for nearly one third (1 155 (23.3%)). Predisposing syncope was more common in patients under 65 years of age(2 066(72.4%) vs. 786(27.6%),χ 2=136.5, P<0.001). Presyncope was more common in patients with neurally mediated syncope (1 972(79.0%) vs.1 908(73.9%), χ 2=17.756, P<0.001). Premonitory symptoms were more common in women(1 837(80.0%) vs. 1 863(73.0%),χ 2=33.432, P<0.001). Presyncope syndrome was more common in patients under 65 years of age (2 482(77.8%) vs. 1 218(73.4%),χ 2=17.523, P=0.001). Cyanosis was more common in ≥65 years old patients (271(18.2%) vs. 369(12.7%), χ 2=23.235, P<0.001). Urinary incontinence was more common in old patients aged ≥65 years(252(15.2%) vs. 345(10.8%), χ 2=19.313, P<0.001). Family history was more common in patients with cardiogenic syncope compared with other types of syncope (264(24.3%) vs. 754(19.5%), χ 2=11.899, P=0.001). Hypertention(1 480(30.5%)), coronary heart disease(1 057(21.4%)), atrial flutter and atrial fibrillation(359(7.2%)), second degree atrioventricular block(236(4.8%)) were common complications of syncope. The proportion of patients with coronary heart disease was significantly higher in cardiac syncope than that of other types of syncope(417(38.4%) vs. 640(16.6%), χ 2=241.376, P<0.001). Other common complications included cerebrovascular diseases (551 (11.1%)) and diabetes mellitus (632(12.8%)). Conclusions:Neurally mediated syncope is the most common syncope in adult Chinese population. Patients with predisposing conditions and premonitory conditions are younger. Presyncope is more common in women. The proportion of family history and coronary heart disease is higher in patients with cardiogenic syncope.

Objective:To investigate the correlation between the X-ray cross-complementary gene 1 (XRCC1) rs25487 gene polymorphism and the effect of neoadjuvant chemoradiotherapy for locally advanced rectal cancer (LARC).Methods:This research was a prospective cohort study consisting of 55 patients with LARC who were treated in the Affiliated Hospital, Guizhou Cancer Hospital of Guizhou Medical University from August 2018 to July 2019. The XRCC1 rs25487 genotype was detected, followed by neoadjuvant chemoradiotherapy. The logistic regression with adjusted confounding factors was used to analyze the relationship between down-staging of T-stage and N-stage and XRCC1 rs25487 gene polymorphism. The stratified analysis was used to explore interactions of neutrophil lymphocyte ratio (NLR) based on logistic regression.Results:The frequencies of all genotypes were in accordance with Hardy-Weinberg equilibrium. After adjusting confounding factors, compared to patients with AA genotype, patients with GG genotype had lower rate of down-staging of T-stage after neoadjuvant radiotherapy ( OR=0.1, P<0.05). However, there was no statistically significant difference between GA and AA genotypes ( P>0.05). There was interactions between AA/GA genotypes and NLR, which affected the down-staging of T-stage after radiotherapy. Conclusions:XRCC1 rs25487 gene polymorphism is associated with the efficacy of neoadjuvant radiotherapy and concurrent system chemotherapy in patients with LARC, which may be used as a predictor of the efficacy of neoadjuvant intensive therapy.

Objective To evaluate the clinical application of Catalyst system in patient positioning during breast cancer radiotherapy,and to analyze its correlation with age and body mass index (BMI).Methods Twenty-four patients with breast cancer who were admitted to our hospital from May to August,2016 were enrolled as subjects.For all patients,auxiliary positioning was made by the optical surface imaging system (CRad Catalyst) before each treatment.The kV-kV imaging was executed weekly to verify positioning.Age,BMI,and setup errors of the two systems in the anterior-posterior (AP),superior-inferior (SI),and left-fight (LR) directions were recorded and analyzed by independent samples t-test and Pearson correlation analysis.Results The C-Rad Catalyst system had a significantly larger setup error in the AP direction than the kV-kV imaging (0.22±0.17 vs.0.18±0.13 cm,P＜0.05).There were no significant differences in setup errors in the SI or LR direction between the two systems (0.23±0.18 vs.0.19±0.15 cm,P＞0.05;0.28±0.28 vs.0.20±0.15 cm,P＞ 0.05).Age and BMI of patients had significant impacts on the C-Rad Catalyst system but the kV-kV imaging (P＞0.05):there were significant differences in setup errors in the AP and SI directions between patients ≤44 years of age and those 45-59 years of age (all P＜0.05);there were significant differences in setup errors in the AP and LR directions between patients ≤44 years of age and those ≥60 years of age (all P＜0.05);there was a significant difference in setup error in the LR direction between patients 45-59 years of age and those ≥ 60 years of age (P＜0.05);there was a significant difference in setup error in the SI direction between patients with BMIs of＜ 25 and ≥ 25 kg/m2 (P＜ 0.05).For patients ≥ 60 years of age,setup error of the C-Rad Catalyst system in the SI direction was correlated with age (r=-0.496,P＜0.05).For patients with BMI of＜25 kg/m2,setup error of the C-Rad Catalyst system in the AP direction was correlated with BMI (r=-0.445,P＜ 0.05).For patients with a BMI of ≥ 25 kg/m2,setup error of the C-Rad Catalyst system in the SI direction was correlated with BMI (r=-0.252,P＜0.05).Conclusions There is significant difference in setup error in the AP direction between the C-Rad Catalyst system and the kV-kV imaging.Age and BMI have impacts on patient positioning by the C-Rad Catalyst system.