To investigate the prevalence and associated factors of fall risk among Chinese older adults, and to examine the roles of urban-rural differences, regional disparities, physical health status, and psychosocial factors in falls among this population, thereby providing evidence for tailored fall prevention strategies.

Objective To investigate the frequency and dose of X-ray computed tomography (CT) medical exposure in Shantou City, and to evaluate the collective effective dose burden of residents caused by CT medical exposure. Methods The study subjects were selected using the stratified random sampling method from CT scanners in all medical institutions in Shantou City in 2020. CT application units were divided into the four tiers of municipal hospitals, district hospitals, subdistrict hospitals, and private hospitals, and 50% of the hospitals in each tier were randomly selected according to the number of hospitals in the tier. The study analyzed CT dose index results, CT scanning standard conditions, and the distribution of characteristic doses of medical exposure to evaluate the dose burden of residents in Shantou City caused by CT medical exposure. Results There were 51 CT scanners in medical institutions in Shantou City. By the end of 2020, the average number of CT scanners per million population was 9.30, and the frequency of CT medical exposure was 135.24 per 1000 population. Jinping District had the highest number of CT scanners per million population (23.2), while Chaoyang District had the lowest number of CT scanners per million population (3.6). The median and range of effective doses for different scan regions were 1.65 (0.76, 4.49) mSv in the head, 4.12 (1.90, 53.21) mSv in the chest, 5.96 (2.68, 10.25) mSv in the abdomen, and 10.30 (4.12, 12.67) mSv in the lumbar spine. By the end of 2020, the effective dose to the public in Shantou City was 6080.67 Sv·person, and the average annual effective dose per person was 1.10 mSv. Conclusion Medical exposure is the most important factor affecting resident dose burden, particularly the overuse of medical exposure examinations. CT examination is the most significant component of medical exposure causing resident dose burden. Reducing unnecessary medical exposure, ensuring the rational use of CT examination, and properly utilizing personal protective equipment are effective measures to minimize the dose burden on examinees.

ObjectiveTo investigate the effect and mechanism of Sishenwan in restoring the intestinal barrier function in the rat model of diarrhea-predominant irritable bowel syndrome （IBS-D） due to spleen-kidney Yang deficiency based on intestinal flora and short-chain fatty acids. MethodsAfter the delivery of 10 SPF-grade pregnant rats， 4 male suckling rats were kept in each litter for the experiment. The male suckling rats were randomly allocated into blank， model， low-dose （3.51 g·kg^-1） Sishenwan， high-dose （7.02 g·kg^-1） Sishenwan， and Peifeikang （0.54 g·kg^-1） groups， with 8 rats in each group. The blank group was fed conventionally， and the other groups were subjected to mother-child separation and Sennae Folium gavage （1 g·mL^-1， 10 mL·kg^-1） for the modeling of IBS-D due to spleen-kidney Yang deficiency. After the modeling was completed， the rats in Sishenwan groups were administrated with the corresponding dose of Sishenwan decoction by gavage， and the Peifeikang group with bifidobacterium triple live powder+normal saline suspension. The blank and model groups were treated with an equal volume of normal saline by gavage. The general conditions and fecal characteristics of rats were observed. After 2 weeks of administration， the rats were anesthetized for sample collection. The pathological changes of the colon tissue in rats were observed by hematoxylin-eosin staining. Enzyme-linked immunosorbent assay was employed to measure the levels of transforming growth factor-beta （TGF-β）， interleukin-10 （IL-10）， and interleukin-22 （IL-22）. Immumohistochemical staining （IHC） was performed to detect the positive expression of zonula occludens-1 （ZO-1） and occludin in the colon tissue. Western blot was employed to determine the protein levels of ZO-1 and occludin in the colon tissue of rats， and 16S rRNA gene sequencing was performed for intestinal flora. Gas chromatography-mass spectrometry was employed to determine the content of short-chain fatty acids （SCFAs） in the cecum contents of rats. ResultsThe colon tissue in the blank group presented a clear structure， neat glands， and no inflammatory cell infiltration. In the model group， the colon tissue showcased a disorganized structure， irregular arrangement of glands， and inflammatory cell infiltration. Compared with the model group， the low-dose and high-dose Sishenwan groups and the Peifeikang group exhibited an intact colon tissue structure， regular arrangement of glands， and reduced inflammatory cell infiltration. Compared with the blank group， the modeling lowered the levels of TGF-β， IL-10， and IL-22 in the serum （P<0.01）， down-regulated the protein levels of ZO-1 and occludin in the colon tissue （P<0.01）， and decreased the content of acetic acid and propionic acid and increased the content of butyric acid in cecum contents （P<0.05）. Compared with the model group， low-dose and high-dose Sishenwan raised the levels of TGF-β， IL-10， and IL-22 in the serum （P<0.05， P<0.01）， and Peifeikang elevated the levels of TGF-β and IL-10 in the serum （P<0.01）. High-dose Sishenwan and Peifeikang up-regulated the protein levels of ZO-1 and occludin （P<0.05， P<0.01）， increased the content of acetic acid and propionic acid in cecum contents （P<0.05）， and decreased the content of butyric acid （P<0.05）. The 16S rRNA gene sequencing results showed that the intestinal flora structure of the model group changed compared with that of the blank group. Compared with the model group， Sishenwan and Peifeikang increased the relative abundance of Lachnospiraceae， Muribaculaceae， Akkermansiaceae， Ligilactobacillus， UBA3282， Akkermansia， and Corynebacterium while reducing the relative abundance of Oscillospiraceae， Desulfovibrionaceae， Lactobacillus， Romboutsia， and Desulfovibrio. They can restore the intestinal flora structure similar to that in the blank group. ConclusionSishenwan can alleviate diarrhea symptoms and colonic mucosal inflammation， increase the expression of tight junction proteins in the colonic mucosa， and strengthen the intestinal barrier in IBS-D rats with the syndrome of spleen-kidney Yang deficiency. The mechanism of action may be related to optimizing the structure and balance of intestinal flora and regulating the SCFAs， and the effect of high-dose Sishenwan is obvious.

ObjectiveTo investigate the effect and mechanism of Sishenwan in restoring the intestinal barrier function in the rat model of diarrhea-predominant irritable bowel syndrome （IBS-D） due to spleen-kidney Yang deficiency based on intestinal flora and short-chain fatty acids. MethodsAfter the delivery of 10 SPF-grade pregnant rats， 4 male suckling rats were kept in each litter for the experiment. The male suckling rats were randomly allocated into blank， model， low-dose （3.51 g·kg^-1） Sishenwan， high-dose （7.02 g·kg^-1） Sishenwan， and Peifeikang （0.54 g·kg^-1） groups， with 8 rats in each group. The blank group was fed conventionally， and the other groups were subjected to mother-child separation and Sennae Folium gavage （1 g·mL^-1， 10 mL·kg^-1） for the modeling of IBS-D due to spleen-kidney Yang deficiency. After the modeling was completed， the rats in Sishenwan groups were administrated with the corresponding dose of Sishenwan decoction by gavage， and the Peifeikang group with bifidobacterium triple live powder+normal saline suspension. The blank and model groups were treated with an equal volume of normal saline by gavage. The general conditions and fecal characteristics of rats were observed. After 2 weeks of administration， the rats were anesthetized for sample collection. The pathological changes of the colon tissue in rats were observed by hematoxylin-eosin staining. Enzyme-linked immunosorbent assay was employed to measure the levels of transforming growth factor-beta （TGF-β）， interleukin-10 （IL-10）， and interleukin-22 （IL-22）. Immumohistochemical staining （IHC） was performed to detect the positive expression of zonula occludens-1 （ZO-1） and occludin in the colon tissue. Western blot was employed to determine the protein levels of ZO-1 and occludin in the colon tissue of rats， and 16S rRNA gene sequencing was performed for intestinal flora. Gas chromatography-mass spectrometry was employed to determine the content of short-chain fatty acids （SCFAs） in the cecum contents of rats. ResultsThe colon tissue in the blank group presented a clear structure， neat glands， and no inflammatory cell infiltration. In the model group， the colon tissue showcased a disorganized structure， irregular arrangement of glands， and inflammatory cell infiltration. Compared with the model group， the low-dose and high-dose Sishenwan groups and the Peifeikang group exhibited an intact colon tissue structure， regular arrangement of glands， and reduced inflammatory cell infiltration. Compared with the blank group， the modeling lowered the levels of TGF-β， IL-10， and IL-22 in the serum （P<0.01）， down-regulated the protein levels of ZO-1 and occludin in the colon tissue （P<0.01）， and decreased the content of acetic acid and propionic acid and increased the content of butyric acid in cecum contents （P<0.05）. Compared with the model group， low-dose and high-dose Sishenwan raised the levels of TGF-β， IL-10， and IL-22 in the serum （P<0.05， P<0.01）， and Peifeikang elevated the levels of TGF-β and IL-10 in the serum （P<0.01）. High-dose Sishenwan and Peifeikang up-regulated the protein levels of ZO-1 and occludin （P<0.05， P<0.01）， increased the content of acetic acid and propionic acid in cecum contents （P<0.05）， and decreased the content of butyric acid （P<0.05）. The 16S rRNA gene sequencing results showed that the intestinal flora structure of the model group changed compared with that of the blank group. Compared with the model group， Sishenwan and Peifeikang increased the relative abundance of Lachnospiraceae， Muribaculaceae， Akkermansiaceae， Ligilactobacillus， UBA3282， Akkermansia， and Corynebacterium while reducing the relative abundance of Oscillospiraceae， Desulfovibrionaceae， Lactobacillus， Romboutsia， and Desulfovibrio. They can restore the intestinal flora structure similar to that in the blank group. ConclusionSishenwan can alleviate diarrhea symptoms and colonic mucosal inflammation， increase the expression of tight junction proteins in the colonic mucosa， and strengthen the intestinal barrier in IBS-D rats with the syndrome of spleen-kidney Yang deficiency. The mechanism of action may be related to optimizing the structure and balance of intestinal flora and regulating the SCFAs， and the effect of high-dose Sishenwan is obvious.

BACKGROUND:As a unique structure of the cervical spine,the occurrence,development and progression of the uncovertebral joint directly affect the stability and range of motion of the cervical spine,and are also closely related to the pathogenesis of cervical spondylosis.A thorough understanding of the developmental characteristics of the uncovertebral joint is of great significance for the pathogenesis,diagnosis,and treatment of cervical spondylosis. OBJECTIVE:By using imaging and three-dimensional reconstruction technology to measure and observe the cervical uncinate process-related angle in a large sample of different age groups,the aim is to reveal the characteristics of its changes with age and vertebral growth,as well as its relationship with cervical spine stability. METHODS:Using a retrospective research design,we collected 1 447 cases of raw CT imaging data that meet the study requirements for complete cervical spine segments.The raw data were imported into Mimics 21.0 software in DICOM format for post-processing and measurement of angle of uncinate process and sagittal angle of uncinate process.The data were grouped based on gender,age,and side. RESULTS AND CONCLUSION:(1)With the increase of vertebral sequence,the angle of uncinate process increased in a V-shaped shape,and the lowest peak was at C5.The overall population showed a sharp peak with the increase of age,and the peak value mostly occurred in the age range of 30-39 years.(2)The sagittal angle of the uncinate process increased like a fishhook with the increase of the vertebral sequence,and the overall angle of the uncinate process increased with age,and the peak value mostly occurred in the age range of 20-29 years.The uncinate process angle and sagittal angle showed only partial significant differences between sides and genders(P<0.05).(3)It is concluded that the angle of the uncinate process increased with the increase of vertebral sequence in a V-shaped manner.The sagittal angle of the uncinate process increases like a fish hook with increasing vertebral order,while the two angles generally peak with increasing age.The angle of the uncinate process is about 131°,which may be closely related to the stability of the cervical spine,while the sagittal angle of the uncinate process is about 14°,and its function may play a certain role in limiting the excessive rotation of the cervical spine.

Background::Findings on the association of genetic factors and colorectal cancer (CRC) survival are limited and inconsistent, and revealing the mechanism underlying their prognostic roles is of great importance. This study aimed to explore the relationship between functional genetic variations and the prognosis of CRC and further reveal the possible mechanism.Methods::We first systematically performed expression quantitative trait locus (eQTL) analysis using The Cancer Genome Atlas (TCGA) dataset. Then, the Kaplan-Meier analysis was used to filter out the survival-related eQTL target genes of CRC patients in two public datasets (TCGA and GSE39582 dataset from the Gene Expression Omnibus database). The seven most potentially functional eQTL single nucleotide polymorphisms (SNPs) associated with six survival-related eQTL target genes were genotyped in 907 Chinese CRC patients with clinical prognosis data. The regulatory mechanism of the survival-related SNP was further confirmed by functional experiments.Results::The rs71630754 regulating the expression of endoplasmic reticulum aminopeptidase 1 ( ERAP1) was significantly associated with the prognosis of CRC (additive model, hazard ratio [HR]: 1.43, 95% confidence interval [CI]: 1.08-1.88, P = 0.012). The results of dual-luciferase reporter assay and electrophoretic mobility shift assay showed that the A allele of the rs71630754 could increase the binding of transcription factor 3 (TCF3) and subsequently reduce the expression of ERAP1. The results of bioinformatic analysis showed that lower expression of ERAP1 could affect the tumor immune microenvironment and was significantly associated with severe survival outcomes. Conclusion::The rs71630754 could influence the prognosis of CRC patients by regulating the expression of the immune-related gene ERAP1. Trial Registration::No. NCT00454519 (https://clinicaltrials.gov/)

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of national bloodstream infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:During the study period，9 035 strains of Gram-negative bacteria were collected from 51 hospitals，of which 7 895（87.4%）were Enterobacteriaceae and 1 140（12.6%）were non-fermenting bacteria. The top 5 bacterial species were Escherichia coli（ n=4 510，49.9%）， Klebsiella pneumoniae（ n=2 340，25.9%）， Pseudomonas aeruginosa（ n=534，5.9%）， Acinetobacter baumannii complex（ n=405，4.5%）and Enterobacter cloacae（ n=327，3.6%）. The ESBLs-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus spp. were 47.1%（2 095/4 452），21.0%（427/2 033）and 41.1%（58/141），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（58/4 510）and 13.1%（307/2 340）；62.1%（36/58）and 9.8%（30/307）of CREC and CRKP were resistant to ceftazidime/avibactam combination，respectively. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 59.5%（241/405），while less than 5% of Acinetobacter baumannii complex was resistant to tigecycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 18.4%（98/534）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of main Gram-negative bacteria resistance among different regions，with statistically significant differences in the prevalence of CRKP and CRPA（ χ2=20.489 and 20.252， P<0.001）. The prevalence of CREC，CRKP，CRPA，CRAB，ESBLs-producing Escherichia coli and Klebsiella pneumoniae were higher in provinicial hospitals than those in municipal hospitals（ χ2=11.953，81.183，10.404，5.915，12.415 and 6.459， P<0.01 or <0.05），while the prevalence of CRPA was higher in economically developed regions（per capita GDP ≥ 92 059 Yuan）than that in economically less-developed regions（per capita GDP <92 059 Yuan）（ χ2=6.240， P=0.012）. Conclusions:The proportion of Gram-negative bacteria in bloodstream infections shows an increasing trend，and Escherichia coli is ranked in the top，while the trend of CRKP decreases continuously with time. Decreasing trends are noted in ESBLs-producing Escherichia coli and Klebsiella pneumoniae. Low prevalence of carbapenem resistance in Escherichia coli and high prevalence in CRAB complex have been observed. The composition ratio and antibacterial spectrum of bloodstream infections in different regions of China are slightly different，and the proportion of main drug resistant bacteria in provincial hospitals is higher than those in municipal hospitals.

Objective:To explore the developmental characteristics of event-related potential(ERP) in cognitive function of recognition memory in children aged 6-12.Methods:A total of 130 normal children were divided into seven age groups (6 ( n=20), 7 ( n=17), 8 ( n=23), 9 ( n=24), 10 ( n=19), 11 ( n=15), and 12 years old ( n=12)) to perform a picture study-recognition task and record the reaction time, accuracy, and ERP components of all participants. SPSS 22.0 software was used for data analysis. Single factor analysis of variance and trend of variance were used to compare the response time and accuracy of 7 groups of children during the recognition stage. Pearson correlation analysis was used to study the correlation between the amplitude of the central midline N2 component and age. Paired t-test was used to examine the old/new effects of the amplitude of midfrontal N2 and midparietal P3 waves. Results:(1) The differences of recognition ability ( F(6, 123)=2.476, P<0.05), old picture reaction time ( F(6, 123)=6.461, P<0.001), and new picture reaction time ( F(6, 123)=4.163, P<0.001) among 7 age groups of children were statistically significant. Recognition ability of children aged 6 (0.61±0.24) was lower than those of 8-12 years old children((0.76±0.27), (0.76±0.10), (0.73±0.11), (0.75±0.10), (0.70±0.17) respectively)(all P<0.05). The reaction time of the old picture showed no difference among the children aged 6-9 (all P>0.05), and the reaction time of old picture of children aged 12 was shorter than those of 6-10 years old children (all P<0.01). There was no significant difference in the reaction time of new pictures among the children aged 6-10 (all P>0.05), and which in children aged 12 was shorter than those in 6-10 years old children(all P<0.01). (2) Age was positively correlated with the amplitude of the N2 component in the central region under the new ( r=0.488, P<0.001) and old picture( r=0.452, P<0.001) conditions. (3)At 6 years old, children showed old/new effects on the mid-frontal electrodes. At 7 years old, there were no old/new effects in either the mid-frontal or mid-parietal regions. From 8 to 9 years old, old/new effects appeared in the mid-parietal lobe. At 10 years old, old/new effects were present in both the mid-frontal and mid-parietal regions. At 11 years old, the mid-parietal lobe showed old/new effects. Finally, at 12 years old, negative old/new effects could be observed in both the mid-frontal and mid-parietal regions. Conclusion:There are three periods of changes in the behavior of picture recognition memory in school-age children. At ages 6-7, the accuracy rate is relatively low; at ages 8-9, it improves; and between ages 10-12, the accuracy rate stabilizes while also enabling faster judgments.Children's recognition memory retrieval process is more complex than their behavioral performance. Children have different tendencies toward strategies, but strategic transitions in recognition processing are not always beneficial for performance.

Objective:To investigate the clinical effect of super-thin free anterolateral thigh (ALT) flap at the junction plane of superficial and deep fat of superficial fascia to repair the soft tissue defects of the foot.Methods:The clinical data of patients with foot soft tissue defects admitted to Northern Jiangsu People’s Hospital Affiliated to Yangzhou University from June 2017 to December 2022 were retrospectively analyzed. During the operation, the super-thin free ALT flap on the affected side was harvested at the junction of superficial and deep fat of superficial fascia to repair the foot wound. The donor site wound was sutured directly or repaired with full-thickness skin graft. The flap survival and complications were observed after the operation, and the operation effect was evaluated from the following five aspects. (1) The Maryland foot function score was used to evaluate the recovery of foot function. The full score was 100 points, of which 90-100 points were excellent, 75-89 points were good, 50-74 points were fair, and < 50 points were poor. (2) The Vancouver scar scale (VSS) was used to evaluate the scar condition of the foot. The total score was 0-15 points. The higher the score, the more serious the scar. (3) The cold intolerance symptom severity (CISS) scale was used to evaluate the cold tolerance of the affected foot. The total score was 4-100 points. The higher the score, the more serious the symptoms. (4) Measuring static two-point discrimination to evaluate foot sensation, the smaller the measured value, the better the sensory recovery. (5) The satisfaction of patients with foot appearance was investigated, which was divided into five grades: very satisfied, satisfied, general, dissatisfied and very dissatisfied. Descriptive analysis of the data was performed using SPSS 26.0 software.Results:A total of 13 patients with foot soft tissue defects were enrolled, including 8 males and 5 females. The mean age was 54.7 years (range, 39-70 years). There were 10 cases of left foot and 3 cases of right foot. The wound area after thorough debridement ranged from 5.5 cm ×5.0 cm to 22.0 cm ×18.0 cm. The operation time was (145.1 ± 30.6) min. The area of the flap was 6.0 cm×5.5 cm to 23.5 cm×19.0 cm, and the thickness was (5.2 ± 1.1) mm (range, 3.0- 6.5 mm). The wound at the donor site was sutured directly in 9 cases, and coverd with the abdominal full-thickness skin graft in 4 cases. After the operation, 1 patient had partial epidermal necrosis at the distal end of the flap, 1 patient had venous crisis.The flaps survived after symptomatic treatment. The remaining 11 flaps survived smoothly. The patients were followed up for 12 to 20 months, with an average of 16 months. The foot flaps were soft and free of damage, and no secondary fat reduction or plastic surgery was required. There were no complications such as wound dehiscence, skin graft necrosis, muscle hernia, and quadriceps weakness in 13 cases of donor site except for hypoesthesia caused by scar hyperplasia in 4 cases with skin graft. At the last follow-up, the Maryland foot function score was (87.4±7.3) points, of which 7 cases were excellent, 4 cases were good, and 2 cases were fair. The excellent and good rate was 11/13. The foot scar was not obvious, the VSS score was (3.2±1.2) points. The foot was more tolerant to cold and the sensory recovery was better, the CISS score was (37.5±7.1) points and the static two-point discrimination was (13.9±1.0) mm. One month after the operation, the results of patients’ satisfaction with foot appearance were as follows: 11 cases were very satisfied and 2 cases were satisfied.Conclusion:The super-thin free ALT flap is obtained at the junction plane of superficial and deep fat of superficial fascia to repair the soft tissue defect of the foot, which can optimize the operation time. The appearance and function of the foot recover well after the operation, avoiding the secondary shaping operation, reducing the damage to the donor site, and the patients are satisfied.

Objective:To investigate the effect of immune checkpoint inhibitors on reducing residual lymph node metastasis in patients with gastric cancer.Methods:The cohort of this retrospective study comprised patients from Nanfang Hospital of Southern Medical University and the First Affiliated Hospital of Xiamen University who had undergone systemic treatment prior to gastrectomy with D2 lymphadenectomy and had achieved Grade 1 primary tumor regression (TRG1) from January 2014 to December 2023. After exclusion of patients who had undergone preoperative radiotherapy, data of 58 patients (Nanfang Hospital: 46; First Affiliated Hospital of Xiamen University: 12) were analyzed. These patients were allocated to preoperative chemotherapy (Chemotherapy group, N=36 cases) and preoperative immunotherapy plus chemotherapy groups (Immunotherapy group, N=22 cases). There were no significant differences between these groups in sex, age, body mass index, diabetes, tumor location, pathological type, Lauren classification, tumor differentiation, pretreatment depth of invasion by primary tumor, pretreatment lymph node stage, pretreatment clinical stage, mismatch repair protein status, number of preoperative treatment cycles, or duration of preoperative treatment (all P>0.05). The primary outcome measure was postoperative lymph node downstaging. Secondary outcomes included postoperative depth of invasion by tumor, number of lymph nodes examined, and factors affecting residual lymph node metastasis status. Results:Lymph node downstaging was achieved significantly more often in the Immunotherapy group than the Chemotherapy group (pN0: 90.9% [20/22] vs. 61.1% [22/36]; pN1: 4.5% [1/22] vs. 36.1% [13/36]; pN2: 4.5% [1/22) vs. 0; pN3: 0 vs. 2.8% [1/36], Z=-2.315, P=0.021). There were no significant difference between the two groups in number of lymph nodes examined (40.5±16.3 vs. 40.8±17.5, t=0.076, P=0.940) or postoperative depth of invasion by primary tumor (pT1a: 50.0% [11/22] vs. 30.6% [11/36]; pT1b: 13.6% [3/22] vs. 19.4% [7/36]; pT2: 13.6% [3/22] vs. 13.9% [5/36]; pT3: 13.6% [3/22] vs. 25.0% [9/36]; pT4a: 9.1% [2/22] vs. 11.1% [4/36], Z=-1.331, P=0.183). Univariate analysis revealed that both preoperative treatment regimens were associated with residual lymph node metastasis status in patients whose primary tumor regression was TRG1 (χ 2=6.070, P=0.014). Multivariate analysis incorporated the following factors: pretreatment depth of invasion by primary tumor, pretreatment lymph node stage, pretreatment clinical stage, number of preoperative treatment cycles, and preoperative treatment duration. We found that a combination of immunotherapy and chemotherapy administered preoperatively was an independent protective factor for reducing residual lymph node metastases in study patients whose primary tumor regression was TRG1 (OR=0.147, 95%CI: 0.026–0.828, P=0.030). Conclusion:Compared with preoperative chemotherapy alone, a combination of preoperative immunotherapy and chemotherapy achieved greater reduction of residual lymph node metastases in the study patients who achieved TRG1 tumor regression in their primary lesions.