Objective To establish a fluorescent recombinase-aided amplification (RAA) assay for detection of Strongyloides stercoralis nucleic acid and to preliminarily evaluate its performance. Methods Six sets of specific primers targeting S. stercoralis 18S ribosomal RNA (18S rRNA) gene and one fluorescent probe were designed and synthesized. The optimal primer-probe set was determined through systematic screening and optimization to establish the fluorescent RAA assay. The assay was evaluated using S. stercoralis genomic DNA at concentrations of 100, 10, and 1 pg/μL, and 100, 10, and 1 fg/μL, as well as recombinant pUC57 plasmids containing the target gene fragments at 1 × 10⁵, 1 × 10⁴, 1 × 10³, 1 × 10², 1 × 10¹, 1 × 10⁰ copies/reaction, to determine the analytical sensitivity. Genomic DNA from Ascaris lumbricoides, Ancylostoma duodenale, Enterobius vermicularis, Angiostrongylus cantonensis, Trichinella spiralis, Clonorchis sinensis, Schistosoma japonicum, and Taenia saginata was used to assess assay specificity. A total of 25 stool samples from patients suspected of S. stercoralis infection were tested by the modified Baermann funnel technique, PCR, and the established fluorescent RAA assay. The sensitivity, specificity, concordance rate and their 95% confidence intervals (CI) of these three techniques were estimated, and agreement between methods was evaluated using the Kappa coefficient. Results Exo-4 was identified as the optimal primer set screened from the six primer sets, and the best amplification performance was achieved when the final concentrations of the forward and reverse primers were 0.44 μmol/L and a probe concentration was 0.20 μmol/L. The limit of detection of the fluorescent RAA assay was 100 fg/μL for genomic DNA of S. stercoralis and 1 × 10⁰ copies/reaction for recombinant plasmids. Specific fluorescence signals were detected within 5 min, with no cross-reactivity observed with A. lumbricoides, A. duodenale, E. vermicularis, A. cantonensis, T. spiralis, C. sinensis, S. japonicum, or T. saginata. Among the 25 clinical stool samples from patients suspected of S. stercoralis infections, the modified Baermann funnel technique and fluorescent RAA assay detected 19 positives and 6 negatives, whereas PCR detected 18 positives and 7 negatives. The fluorescent RAA assay showed a sensitivity of 100.00% [95% CI: (82.35%, 100.00%)], specificity of 100.00% [95% CI: (54.07%, 100.00%)], concordance rate of 100.00% [95% CI: (86.28%, 100.00%)], and a Kappa coefficient of 1.00 [95% CI: (1.00, 1.00)] (P < 0.001) relative to the modified Baermann funnel technique, and a sensitivity of 100.00% [95% CI: (81.47%, 100.00%)], specificity of 85.71% [95% CI: (42.13%, 99.64%)], concordance rate of 96.00% [95% CI: (79.65%, 99.90%)], and a Kappa coefficient of 0.90 [95% CI: (0.70, 1.00)] (P < 0.001). Positive amplification products emitted green fluorescence under a portable blue-light device, enabling visual interpretation of results. Conclusions The fluorescent RAA assay established in this study is rapid, highly sensitive, and highly specific. It enables detection of S. stercoralis nucleic acid under isothermal conditions and allows visual interpretation of results, providing a novel tool for rapid clinical diagnosis and field screening of S. stercoralis infections.

Objective:To investigate the impact of postoperative complications on adverse outcomes following curative-intent resection for gallbladder cancer (GBC).Methods:The multi-center real-world study was conducted. The clinicopathological data of 629 patients with GBC, who were admitted to 14 medical centers including The First Affiliated Hospital of Army Medical University from the national multicenter database of Biliary Surgery Group of Elite Group of Chinese Journal of Digestive Surgery, from April 2020 to April 2024 were collected. There were 225 males and 404 females, aged (64±10)years. Patients underwent open curative-intent resection for GBC. Observation indicators: (1)surgery, postoperative complica-tions and adverse outcomes; (2) analysis of risk factors affecting postoperative adverse outcomes in patients and population attributable fraction (PAF). Missing data in predictor variables were addressed using multiple imputation with chained equations, while cases with missing outcome variables were addressed using the "multiple imputation then deletion (MID)" strategy. The severity of multicollinearity among independent variables was assessed using the variance inflation factor (VIF) test. Multivariable possion regression models with log link and robust error variance were construc-ted incorporating restricted cubic splines (3 knots) to address nonlinear relationships in continuous variables, calculating adjusted relative risk ( RR) with corresponding 95% confidence interval ( CI). Adjusted PAF was calculated for each imputed dataset using the AF package of R software, with subsequent pooling performed according to Rubin's rules. Results:(1) Surgery, postoperative complications and adverse outcomes. All 629 patients underwent curative-intent resection for GBC, of which 143 cases had postoperative complications, including 68 cases of intra-abdominal ascites, 39 cases of pulmonary infection, 21 cases of bile leakage, 12 cases of intra-abdominal hemorrhage, 11 cases of liver failure, 10 cases of pan-creatic fistula, 10 cases of wound infection, 10 cases of gastroparesis, 7 cases of cholangitis, 7 cases of sepsis. The same patient could have more than one kind of complication. Of 629 patients, there were 19 cases of postoperative 90-day death and 11 cases of missing data, 42 cases with post-operative 90-day reoperation and 7 cases with missing data, 44 cases with postoperative 90-day readmission and 3 cases with missing data, 155 cases with prolonged postoperative hospital stay and 3 cases with missing data. (2) Analysis of risk factors affecting the postoperative adverse outcomes in patients and PAF. Results of multivariate analysis showed that pulmonary infection and liver failure were independent risk factors for postoperative 90-day mortality ( RR=3.74, 12.15, 95% CI as 1.18-11.83, 1.98-74.48, P<0.05). Pulmonary infection demons-trated the highest PAF as 4.61% (95% CI as 3.94%-5.28%, P<0.05). Intra-abdominal ascites, pulmonary infection, bile leakage, and intra-abdominal hemorrhage were independent risk factors for post-operative 90-day reoperation ( RR=4.80, 3.62, 3.46, 4.99, 95% CI as 2.49-9.26, 1.42-9.21, 1.34-8.92, 1.55-16.06, P<0.05). Intra-abdominal ascites demonstrated the highest PAF as 8.65% (95% CI as 8.22%-9.08%, P<0.05). Intra-abdominal ascites, bile leakage, and liver failure were independent risk factors for postoperative 90-day readmission ( RR=6.20, 3.33, 14.33, 95% CI as 3.21-11.95, 1.33-8.35, 3.72-55.28, P<0.05). Intra-abdominal ascites demonstrated the highest PAF as 9.11% (95% CI as 8.85%-9.37%, P<0.05). Intra-abdominal ascites, pulmonary infection, bile leakage, liver failure, and wound infection were independent risk factors for prolonged postoperative hospital stay ( RR=2.29, 2.21, 2.26, 2.14, 3.35, 95% CI as 1.63-3.23, 1.41-3.46, 1.32-3.86, 1.11-4.13, 1.70-6.60, P<0.05). Intra-abdominal ascites demonstrated the highest PAF as 6.03% (95% CI as 5.71%-6.35%, P<0.05). Conclusion:Pulmonary infection is the most significant risk factor for postoperative 90-day mortality after curative-intent resection for GBC, while intra-abdominal ascites is the most significant risk factor for postoperative 90-day reoperation, postoperative 90-day readmission, and prolonged postoperative hospital stay.

Objective:To investigate the clinical value of continuous Bougie tube use in symmetrical three-port laparoscopic sleeve gastrectomy (LSG).Methods:The retrospective cohort study was conducted. The clinical data of 105 patients who underwent symmetrical three-port LSG at The First Hospital of Shanxi Medical University from October 2021 to October 2024 were collected. There were 57 males and 48 females, aged 27(range, 19-59)years. Of the 105 patients, 52 cases with continuous Bougie tube use during the surgery were divided into continuous group, while 53 cases with intermittent Bougie tube use were divided into intermittent group. Observation indicators: (1) surgical situations; (2) complications. Comparison of measurement data with normal distribution between groups was conducted using the independent sample t test. Comparison of measurement data with skewed distribution between groups was conducted using the Mann-Whitney U test. Comparison of count data between groups was conducted using the chi-square test. Results:(1) Surgical situations. All 105 patients underwent symmetrical three-port LSG. The operation time was (57±4)minutes versus (76±4)minutes for the continuous group and the intermittent group, volume of intraoperative blood loss was (26±6)mL versus (59±9)mL, time to first out-of-bed activities was (218±8)minutes versus (299±9)minutes, time to first anal exhaust was (19.6±2.9)hours versus (25.8±2.8)hours, visual analogue scale score for pain at 6 hours postoperatively was 2.3±1.0 versus 4.7±1.0, and duration of postoperative hospital stay was (1.5±0.6)days versus (3.1±0.9)days for the two groups, respectively. There were significant differences in the above indicators between the two groups( t=26.92, 22.31, 48.91, 11.15, 13.25, 10.21, P<0.05). (2) Complications. No severe postopera-tive complication occurred in any of the 105 patients. There were 26 cases and 38 cases with nausea and vomiting at 2 hours postoperatively, showing a significant difference between them ( χ2=5.19, P<0.05). Conclusion:Compared to intermittent Bougie tube use, continuous Bougie tube use during symmetrical three-port LSG can significantly shorten operation time and duration of postoperative hospital stay, reduce intraoperative bleeding and postoperative pain, accelerate recovery of patients, and lower the incidence of complications.

Objective To summarize the best evidence of early rehabilitation management of hand function in patients with hand burn,and provide basis for medical personnel to carry out early rehabilitation management of hand burn.Methods According to the 5S model,all evidence on early rehabilitation management of hand function in patients with hand burns was retrieved from databases and websites including UpToDate,BMJ Best Practice,NICE,RNAO,GIN,and so on.The retrieved evidence included clinical decisions,guidelines,evidence summaries,expert consensuses,systematic reviews,Meta analysis.The search period of the summary of best evidence,expert concensus and guidelines are from the establishment of the database to December 20,2024,and the search period of the systematic reviews is from January 1,2019 to December 20,2024.Quality evaluation of literature,evidence extraction and summary were conducted.The evidence was graded according to JBI evidence pre-grading system 2014.Results Totally 17 pieces of the literature were included,including 1 clinical decision,4 guidelines,6 evidence summaries,3 expert consensus articles,and 3 systematic reviews.Totally pieces of best evidence were summarized,including 7 aspects of assessment,hand positioning,treatment of edema,dressing,use of orthotics,joint mobility training,and health education.Conclusion This study summarized the best evidence of early rehabilitation management of hand function in patients with hand burn,and provided evidence-based evidence for clinical rehabilitation management plan.According to the clinical situation,the medical staff can apply the evidence to clinical practice,so as to improve the hand function and quality of life of patients.

Objective:To investigate the effect of aerobic exercise with acupuncture needles on the learning and memory ability in rats subjected to middle cerebral artery occlusion/reperfusion(MCAO/R)and to explore the underly-ing mechanisms.Method:Male SD rats were randomly divided into four groups:sham,model,aerobic exercise with acupunc-ture needles,and inhibitor groups(n=12 per group).In the sham group,only the left common carotid artery,in-ternal carotid ar tery,and external carotid artery were exposed without inducing ischemia,while the other three groups underwent MCAO/R modeling.To establish an MCAO/R model with reduced NLRP3 expression,rats in the inhibitor group received an intraperitoneal injection of MCC950 60 minutes before modeling.On the first day of post-modeling,the Zea-Longa score and T2 WI were used to screen the MCAO/R rats.From the second day,rats in the aerobic exercise with acupuncture needles and the inhibitor groups were underwent a 14-day intervention.The acupoints were selected for"Shenting"(GV 24)and"Baihui"(GV 20),with sparse waveform at a frequency 2/10Hz and a current intensity of 1-3mA.Simultaneously,the rats performed tread-mill exercise,with speeds of 4m/min(day 1-3),6m/min(day 4-7),and 8m/min(day 8-14)for 30min/day.Afterthe intervention,neurological function was reassessed,and the new object recognition test was used to measure the learning and memory ability,and the pathological changes of the hippocampus were observed by HE staining.The protein expressions of NLRP 3,GSDMD,and Caspase-1 were detected by Western Blot and immunofluorescence,ELISA detected the contents of ILL-1β and IL-18,the expression and localization of IBA 1 and NLRP 3 were detected by double immunofluorescent staining.Result:The hippocampal neurons in the ischemic side of the rats were loosely and disorderly arranged in the model group.Compared to the sham group,the model group showed significantly impaired neurological func-tion and novel object recognition ability(P＜0.01),with significant increased expression of NLRP 3,GSDMD,and Caspase-1(P＜0.01),and elevated ILL-lβ and IL-18 contents(P＜0.01).In addition,IBA 1 and NLRP 3 fluo-rescence expression were enhanced(P＜0.01),and many IBA 1+/NLRP 3+double-positive cells were observed un-der the microscope(P＜0.01).Compared with the model group,the aerobic exercise with acupuncture needles group showed significant improvements in neurological function and the new object recognition index(P＜0.05,P＜0.01),reduced hippocampal pathological injury,decreased expression of NLRP 3,GSDMD,and Caspase-1 d(P＜0.01)and lower IL-lβ and IL-18 levels(P＜0.05);the activation of microglia and the expression of IBA 1,NL-RP 3 and the number of IBA 1+/NLRP 3+double-positive cells decreased(P＜0.01).The inhibitor group demon-strated even greater improvements in neural function and new object recognition performance than the aerobic exercise with acupuncture needles group(P＜0.05,P＜0.01),with further reductions in NLRP 3,GSDMD,Caspase-1 protein expression(P＜0.01)and lower level of IL-1β,IL-18(P＜0.01,P＜0.05);the microglia activation level,the number,arrangement and morphology of nerve cells were closely resembled those in the sham group,and there was minimal NLRP 3 microglia observed under the microscope(P＜0.01).Conclusion:Aerobic exercise with acupuncture needles at"Shenting"(GV 24)and"Baihui"(GV 20)points could improve the learning and memory function in MACO/R rats by inhibiting microglia pyroptosis and activa-tion,thereby reducing neuroinflammation.

Aim To explore the in vitro anti-human triple-negative breast cancer(TNBC)effect and mech-anism of Austocystin R.Methods MTT assay was used to evaluate the anti-tumor potential of Austocystin R for various human tumor cells and normal cells.Flow cytometry was employed to evaluate the influence on cell cycle progression.mRFP-GFP-LC3 adenovirus transfection was used to evaluate the autophagic flux process.Western blot assay was used to verify the effect of Austocystin R on the expression of related pro-teins.Results The results showed that Austocystin R significantly inhibited the proliferation of multiple tumor cells in a dose-dependent manner,especially for the MDA-MB-231 cells with an IC50 of 1.45μmol·L-1.In addition,Austocystin R increased the protein expression of PTEN,p53,p-p53,p27,p21,and down-regulated the expression of p-PI3K,p-AKT and p-mTOR.Austocystin R can significantly increase the proportion of S-phase MDA-MB-231 cells,inhibit the expression of Cyclin D1,CDK4,CDK6,Rb,Cyclin B1 and CDK1,and promote the expression of Cyclin E1 and CDK2.Austocystin R can promote the autophagic flux process of MDA-MB-231 cells,promote the expres-sion of LC3 Ⅰ/Ⅱ,p-Beclin-1,p-ULK1,HMGB-1 and Atg 14 proteins,and inhibit the expression of Beclin-1,ULK1,p62,ATG 3,ATG 4B,ATG 5,ATG 7,ATG 12,ATG 13 and ATG 16L1 proteins.Conclusion Austo-cystin R can exhibit its anti-TNBC activity by inhibi-ting the PI3K/AKT/mTOR signaling pathway,blocking the cell cycle at the S phase and inducing autophagic cell death.

Objective This study aimed to investigate the antimicrobial resistance profiles of bacterial strains isolated from pediatric intensive care units(PICU)in China for better antimicrobial therapy.Methods Clinical isolates were collected from 17 institutions,including tertiary care children's hospitals and pediatric department of tertiary general hospitals in China from January 1,2020 to December 31,2022.Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated systems.Results were interpreted according to the breakpoints released by the Clinical and Laboratory Standards Institute(CLSI)in 2020.Results A total of 10 688 isolates were collected,including gram-positive organisms(39.2％)and gram-negative organisms(60.8％).The top three organisms were S.aureus(13.6％,1 453/10 688),A.baumannii(10.0％,1 067/10 688),and coagulase-negative Staphylococcus(9.9％,1 058/10 688).Multi-drug resistant organisms(MDROs)were very common in children.The prevalence of methicillin-resistant Staphylococcus aureus(MRSA),carbapenem-resistant Enterobacterales(CRE),carbapenem-resistant E.coli,carbapenem-resistant K.pneumoniae(CRKP),carbapenem-resistant A.baumannii(CRAB),and carbapenem-resistant P.aeruginosa(CRPA)was 41.1％,19.4％,8.8％,30.9％,67.4％,and 28.8％,respectively.Overall,more than 50％of Enterobacteriales isolates were resistant to cephalosporins,while nearly 25％of Enterobacteriales isolates were resistant to carbapenems.MDROs were highly resistant to commonly used antibiotics.More than 80％of CRE and CRAB strains were resistant to all beta-lactam antibiotics.CRE and CRAB showed low resistance rates to tigecycline and polymyxin.CRPA showed lower resistance rates to piperacillin,beta-lactamase inhibitor combinations than the resistance rates to third and fourth generation cephalosporins.All of the Staphylococcus and Enterococcus isolates were susceptible to vancomycin and tigecycline.None of PRSP strains isolated from meningitis and nonmeningitis samples were resistant to rifampicin,vancomycin,or linezolid.The prevalence of β-lactamase-negative ampicillin-resistant(BLNAR)strains was 43.3％in Haemophilus influenzae.Conclusions MDROs were prevalent in PICU.It is necessary to establish an effective multidisciplinary team(MDT)to control the antimicrobial resistance.

Objective:To observe the efficacy and safety of combined lienal polypeptide injection therapy in the treatment of Mycoplasma pneumoniae pneumonia（MPP）in children aged 3 to 14 years old in multiple clinical centers.Methods:A randomized，controlled，multi-center clinical study design was adopted.A total of 240 hospitalized children aged 3 to 14 years old with MPP from 7 hospitals from September 1，2023 to January 31，2024 were included.According to the severity of pneumonia，they were divided into the mild MPP group with 80 cases and the severe MPP/refractory MPP（SMPP/RMPP）group with 160 cases，and then randomly divided into the control group and the experimental group at a ratio of 1 ∶1，using the random number table method.After screening，subjects entered a treatment period of 5 to 7 days.The control group was treated with azithromycin，while the experimental group was treated with azithromycin plus lienal polypeptide injection .The recovery of lung CT，length of hospital stay，duration of fever，cough score，whether mild cases developed into severe or refractory cases，duration of hormone use，use of intravenous immunoglobulin（IVIG），bronchoscopy treatment，and immune function were observed between the two groups to evaluate the efficacy of lienal polypeptide injection.Adverse events after medication，vital signs，blood routine，urine routine，liver function，myocardial enzymes，renal function，and electrocardiogram were observed to evaluate the safety. Results:A total of 231 subjects have completed the trial in the 7 hospitals，including 118 cases in the experimental group and 113 cases in the control group.Main observation index：the rate of lung CT aggravation in the experimental group was lower than that in the control group（2.6% vs 15.3%， P<0.01），and the difference was statistically significant.Secondary indexes：there were no statistically significant differences in the length of hospital stay，duration of fever，cough score，duration of hormone use，whether IVIG treatment was used，the number of bronchoscopy treatment cases，and immunoglobulin between the two groups（all P>0.05）.However，the rate of cases of plastic bronchitis（PB）found under bronchoscopy in the experimental group was lower than that in the control group（0 vs 18.8%， P=0.03），and the difference was statistically significant.Among the mild MPP（72 cases），there were no statistically significant differences in the length of hospital stay，duration of fever，cough score，duration of hormone use，whether IVIG treatment was used，the number of bronchoscopy treatment cases，and the improvement rate of lung CT between the two groups（all P>0.05）.However，compared with the control group，the rate of cases developing into SMPP/RMPP in the experimental group was less（24.3% vs 48.6%， P=0.03），and the difference in IgG before and after treatment was small［0.53（-0.04，1.18）g/L vs 1.33（0.48，2.25）g/L， P=0.01］.Among the SMPP/RMPP cases（159 cases），the rate of cases of PB found under bronchoscopy in the experimental group was less than that in the control group（0 vs 20%， P=0.04），and the rate of cases with aggravated lung CT in the experimental group was less than that in the control group（1.3% vs 19.5%， P<0.01），and the improvement rate of lung CT in the experimental group was higher than that in the control group（88.8% vs 75.3%， P=0.03），with statistically significant differences.There were no statistically significant differences in the length of hospital stay，duration of fever，cough score，duration of hormone use，whether IVIG treatment was used，the number of bronchoscopy treatment cases，and immunoglobulin between the two groups（all P>0.05）.Two cases in the experimental group developed rashes，which improved after the drug was discontinued.There were no serious adverse reactions such as abnormal vital signs like dyspnea and cyanosis due to the use of lienal polypeptide injection.There were no obvious changes in blood routine，liver function，myocardial enzymes，renal function，electrocardiogram，and urine routine values before and after medication compared with the baseline. Conclusion:The combined use of lienal polypeptide injection in the treatment of MPP in children can reduce the probability of the transformation from mild cases to SMPP/RMPP，reduce the rate of aggravation of the image findings，promote the absorption of lung inflammation，reduce the rate of PB found under bronchoscopy，and has good safety.

Objective:To explore the dosimetric characteristics of intensity modulated proton therapy (IMPT), intensity modulated radiation therapy (IMRT) and tomotherapy (TOMO) techniques applied in the irradiation of pediatric whole central nervous system tumors.Methods:Taking the target area of a 14-year-old pediatric patient clinically diagnosed with atypical teratoid/rhabdomyoid tumor, meningeal metastasis by Shandong Cancer Hospital and Institute, and undergoing craniospinal irradiation (CSI) as an example, IMPT, IMRT and TOMO plans were designed respectively based on the clinical prescription of the target area and the limit requirements of organs at risk (OARs). The conformal index (CI), homogeneity index (HI) and gradient index (GI) of each planning target volume, as well as the dose volume index of normal tissues, were evaluated to compare the dosimetric characteristics of the three types of plans.Results:The CI (0.71), HI (0.05) and GI (3.13) of the IMPT plan were comparable to those of IMRT plan (0.80, 0.08, 3.14). The HI (0.03) and GI (2.54) of the TOMO plan were excellent, which were all within the clinically acceptable range. The irradiation dose to parallel organs in the IMPT plan was lower than that in the IMRT and TOMO plan. In the IMPT plan, V 5 of lungs was 2.9%, IMRT plan was 37.6%, and TOMO plan was 43.5%. The D mean of liver in the IMPT plan was 0.01 Gy (RBE), IMRT plan was 6.12 Gy, and TOMO plan was 6.39 Gy. In the IMPT plan, none of the bladder, rectum, and femoral head received the dose, while there was low-dose radiation in both IMRT and TOMO plan. For serial organs adjacent to and within the target area, the D max of spinal cord and brainstem in IMPT plan was 39.89 and 39.88 Gy (RBE), respectively; in IMRT plan, they were 39.43 and 38.59 Gy, respectively; and in TOMO plan, they were 38.41 and 37.69 Gy, respectively. The low-dose area in the IMPT plan was significantly better than the photon radiotherapy plans. Among them, the absolute volume IMPT plan occupied by 10% of the prescribed dose area in the patient's body was reduced by 70.10% compared with IMRT plan and 76.96% compared with TOMO plan; the 30% prescribed dose volume IMPT plan was reduced by 53.49% compared with IMRT plan and 62.51% compared with TOMO plan; the 50% prescribed dose volume IMPT plan was reduced by 39.06% compared with IMRT plan and 42.23% compared with TOMO plan. Conclusions:The IMPT plan demonstrated significantly reduced low-dose exposure and lower doses to parallel OARs compared to both IMRT and TOMO plans in pediatric CSI. The CI, HI and GI of the three plans can all meet the clinical requirements. However, for serial organs adjacent to and within the target area, the D max of the IMPT plan may be higher than that of IMRT and TOMO plans.

Objective:To explore the dosimetric characteristics of proton and photon radiotherapy in the treatment of breast cancer.Methods:Four female breast cancer patients who needed radiotherapy at Shandong Cancer Hospital and Institute from January 2024 to May 2024 were selected as the research subjects. The target area ranges of 4 patients were left-sided breast cancer with lymph node involvement, left-sided breast cancer with lymph node involvement and internal mammary node, right-sided breast cancer with lymph node involvement and internal mammary node and synchronous bilateral breast cancer. Intensity modulated proton therapy (IMPT) and intensity modulated radiation therapy (IMRT) plans were designed respectively based on the prescribed dose in the target area and the limits of organs at risk (tomotherapy plan for bilateral breasts). The conformity index (CI), homogeneity index (HI), gradient index (GI) and organs at risk doses were evaluated. The dosimetric characteristics of IMPT and photon radiotherapy were compared.Results:Both IMPT and photon radiotherapy plans of the 4 breast cancer cases met the clinical dose requirements. The HI value of IMPT plans (0.10-0.14) was comparable to that of photon radiotherapy plans (0.10-0.12), and the average CI of the photon radiotherapy plans was 0.10 higher than that of the IMPT plans, and the average GI was 0.55 lower than that of the IMPT plans. The D mean of ipsilateral lung and heart of IMPT was lower, especially in the low-dose area (V 0-3), which was significantly lower than the photon radiotherapy plans, D mean of ipsilateral lung was reduced by 12.2%, 6.1%, 16.1% and 34.8%, respectively, D mean of heart was reduced by 47.2%, 57.0%, 72.4% and 83.0%, respectively. The ipsilateral lung V 20 of IMPT was not lower than photon radiotherapy plans (unilateral breast: IMPT was 30.0%-34.0%, IMRT was 29.0%-35.9%) . Conclusions:IMPT significantly reduces the D mean to the ipsilateral lung and heart while ensuring dose coverage of the target in breast cancer, preventing more volume of surrounding normal tissues from being irradiated. However, IMPT does not show much more advantage than photon radiotherapy plans in the ipsilateral lung V 20.