Background: To investigate directional deviations between pilot holes and final pedicle screw trajectories in freehand placement and analyze risk factors for misplacement. While pedicle screws are widely used in thoracolumbosacral surgery, directional deviations between pilot holes and final screw trajectories remain understudied as potential risk factors for misplacement. Methods: Thirty-three patients undergoing posterior fixation were prospectively enrolled. Inertial measurement units (IMUs) tracked the spatial positions of pedicle finders and screwdrivers via custom software. Surgeons (n = 6) were stratified into senior, middle, and junior groups. Analyzed variables included the use of tapping, surgeon experience, spinal deformity status, screw tip morphology, and surgical parameters. Results: Among 198 implanted screws (6.00 ± 2.88/patient), all exhibited trajectory deviations (8.12° ± 3.47°). Tapping significantly reduced deviations (7.23° ± 3.23° vs. 8.87° ± 3.31°, p < 0.01). Senior surgeons achieved smaller deviations (7.34° ± 3.33°) than the middle group (8.60° ± 3.51°, p = 0.039) and junior group (8.68° ± 3.49°, p = 0.022). Multivariate analysis confirmed tapping (p = 0.001) and senior experience (p = 0.023) as protective factors. No significant associations emerged for spinal deformity (8.43° ± 3.73° vs. 7.97° ± 3.35°, p = 0.377), screw tip type (cylindrical, 8.43° ± 3.26° vs. tapered, 8.07 ± 3.51°; p = 0.637), obesity, or surgical position parameters. Conclusions Freehand pedicle screw placement consistently produces trajectory deviations from pilot holes, and surgeon experience and tapping are modifiable protective factors. The IMU-based tracking system enables quantitative surgical motion analysis, suggesting its utility for training optimization and technique standardization.

Objective To investigate the causes and management strategies for lower limb ischemic necrosis following xenogeneic heterotopic heart transplantation from a multigene-edited pig to a rhesus monkey. Methods A xenogeneic heterotopic heart transplantation was performed on December 16, 2023, at the Institute of Experimental Animals of Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, using a quintuple-gene-edited pig as the donor and a rhesus monkey as the recipient. On postoperative day (POD) 9, the recipient monkey underwent left lower limb amputation due to ischemic necrosis. Blood samples were collected at various time points after transplantation for analysis of hematologic parameters, liver and renal function, myocardial enzymes, and coagulation profiles. Ultrasound and computed tomography (CT) were used to evaluate anastomotic patency and cardiac structure. Immunological assays, including complement-dependent cytotoxicity (CDC) and IgG/IgM antibody detection, combined with clinical observations, were employed to assess rejection type and therapeutic response. Results The recipient monkey survived for 46 days after transplantation. Echocardiography demonstrated preserved biventricular systolic function in the recipient’s native heart, with left ventricular ejection fraction (LVEF) consistently exceeding 50%. In the donor pig heart, left ventricular endocardial thickening was noted on POD 9, followed by right ventricular endocardial thickening on POD 24, while LVEF remained around 35%. No hyperacute or acute rejection was detected immunologically. CDC positivity ranged between 3.4% and 5.1%, with IgG/IgM antibody binding trends consistent with CDC results. Following amputation, the recipient exhibited elevated inflammatory markers, coagulopathy, and reactive thrombocytosis, which later normalized. Immunohistochemical staining of the necrotic limb revealed arterial and venous thrombosis; however, no T-cell or B-cell infiltration was observed in vascular structures, thrombi, nerves, muscles, fascia, or skin tissues, with CD3 and CD20 staining both negative. Conclusion Limb ischemia after xenogeneic heart transplantation may be associated with lower extremity vascular thrombosis triggered by local trauma in the context of transplantation-induced inflammatory activation and coagulation dysfunction. While no clear lymphocyte-mediated rejection was observed, further studies are needed to explore the potential role of non-lymphocyte-mediated immune mechanisms.

Objectives:To investigate the clinical efficacy of bilateral mini-open Wiltse approach transforami-nal lumbar interbody fusion(MO-TLIF)in the treatment of degenerative lumbar diseases in the elderly.Meth-ods:A retrospective analysis was conducted on 62 elderly patients with single-segment degenerative lumbar diseases who underwent MO-TLIF or minimally invasive transforaminal lumbar interbody fusion(MIS-TLIF)inthe First Affiliated Hospital of Naval Medical University between September 2017 and August 2020.Among them,37 were male and 25 were female,aged 68.0±5.5 years.The patients were divided into the MO-TLIF group(32 cases)and the MIS-TLIF group(30 cases).There were no statistically significant differences between the two groups in terms of gender ratio,age,body mass index(BMI),surgical segment,disease duration,or follow-up time(P＞0.05).The differences between the two groups were compared in terms of operative time,in-traoperative blood loss,intraoperative fluoroscopy,postoperative wound drainage,time to ambulation,hospital stay,complications,and fusion rate.The visual analogue scale(VAS),lumbar Japanese Orthopedic Association(JOA)scores,and Oswestry disability index(ODI)before surgery,at 3 months postoperatively,and at the final follow-up were recorded and compared.Results:The two groups of patients all successfully completed the surgery without significant surgery-related complications.There were no statistically significant differences be-tween the MO-TLIF and MIS-TLIF groups in terms of intraoperative blood loss(80.3±25.1mL vs.72.3±21.8mL),postoperative wound drainage volume(30.7±10.2mL vs.29.3±9.0mL),or hospital stay(5.4±0.9d vs.5.4±0.8d)(P＞0.05).Compared with the MIS-TLIF group,the MO-TLIF group had shorter operative time(90.8±8.8min vs.98.3±8.0min,P=0.001)and fewer number of intraoperative fluoroscopy(4.7±0.7 times vs.7.2±1.4 times,P＜0.001).Both groups showed significant improvement in low back pain VAS score,lumbar JOA score,and ODI at postoperative 3 months and final follow-up compared with preoperative values(P＜0.001),but there were no statistically significant differences between the two groups at the same time points(P＞0.05).At the fi-nal follow-up,no internal fixation-related complications such as screw or rod breakage were observed in both groups,and all the cases achieved bone fusion.Conclusions:Bilateral MO-TLIF can achieve good therapeutic outcomes in treating single-segment degenerative lumbar diseases,which can reduce intraoperative fluoroscopy frequency and shorten operative time comparing with MIS-TLIF.

Objective:To determine the actual metastasis rate of paracolic lymph nodes (PCN) more than 10 cm proximal to rectal tumors and explore the significance of PCN dissection in the prognosis of patients with rectal cancer. ?Methods:This was a prospective observational cohort study. The clinical data of 457 consecutive patients with rectal cancer who underwent radical surgery at the Colorectal Tumor Center of West China Hospital, Sichuan University from January 2015 to May 2022 were included. Inclusion criteria: (1) Pathologically confirmed rectal adenocarcinoma (anal margin ≤ 12 cm); (2) R0 resection was performed with a proximal margin ≥ 10 cm (measured on the in vivo specimen during surgery after intestinal mobilization); (3) For stage IV patients, only those with resectable metastatic lesions by R0 were included; (4) Patients who completed the full course of neoadjuvant therapy (TNT) must meet the surgical window of 8-12 weeks after radiotherapy. Exclusion criteria: tumors located more than 15 cm from the anal margin, synchronous multiple primary colorectal cancers, positive tumor margins, preoperative imaging suggesting lateral lymph node metastasis (LLNM), presence of Lynch syndrome or familial adenomatous polyposis, emergency surgery, recurrence after rectal cancer surgery, T4b tumors requiring combined organ resection, previous radiotherapy and chemotherapy for non-rectal cancer, and those with cardiac, pulmonary, renal and other organ dysfunction that could not tolerate surgery. After standard total mesorectal excision (TME), the proximal intestinal tube was transected at a level more than 10 cm above the lesion, and then intestinal anastomosis or enterostomy was completed. The distance from the tumor edge was marked and measured in vivo during the operation, and lymph nodes were harvested from the fresh specimen. Patients with PCN metastasis beyond 10 cm proximal to the tumor were classified into the positive lymph node group (pPCN group), while those without PCN metastasis beyond 10 cm proximal to the tumor were classified into the negative lymph node group (nPCN group). The differences in clinicopathological characteristics, overall survival (OS) and disease-free survival (DFS) between the two groups were compared, and risk factor analysis and survival analysis of pPCN were performed.Results:There were 16 cases (3.5%) in the pPCN group, 15 cases (3.3%) had central lymph node metastasis; the nPCN group included 441 cases. When comparing the baseline characteristics between the pPCN group and the nPCN group, there was no statistically significant difference in other aspects except that the cN stage was more advanced in the pPCN group ( P=0.006) (all P>0.05). The number of positive mesenteric lymph nodes in the pPCN group was higher than that in the nPCN group ( P<0.001), and the proportion of patients with a total number of harvested lymph nodes ≥12 and the number of lymph nodes with a short diameter >5 mm were both higher (all P<0.05). The proportion of patients with positive lymph nodes within 10 cm and the number of positive lymph nodes within 10 cm were also higher in the pPCN group (both P<0.001). Similar to the clinical TNM staging, the proportions of patients with pT3 and N2 stages, as well as the incidence of poorly differentiated tumors (G3, G4) were higher in the pPCN group ( P<0.001). The results of multivariate analysis showed that among the preoperative pathological characteristic variables, the presence of positive lymph nodes within 10 cm (OR=14.869, 95%CI: 2.993-73.858, P=0.001) and low tumor differentiation grade (OR=7.189, 95%CI: 2.091- 24.714, P=0.002) were independent risk factors for pPCN. The median follow-up time of the patients in this group was 63 (0-63) months. No local recurrence occurred in the pPCN group, and the 5-year OS was 50.0%, which was significantly lower than 78.0% in the nPCN group (HR=2.496, 95%CI: 1.263-4.930, P=0.008). The 3-year DFS was 43.8%, also significantly lower than 77.7% in the nPCN group (HR=2.950, 95%CI:1.488-5.846, P=0.002). Multivariate Cox prognostic analysis suggested that age ≥65 years (HR=2.041, 95%CI: 1.375-3.031, P<0.001), female (HR=1.838, 95%CI: 1.171-2.884, P=0.008), tumor length ≥3 cm (HR=1.747, 95%CI: 1.076-2.834, P=0.024), more advanced cT stage (HR=2.865, 95%CI: 1.234-6.653, P=0.014), and cM1 (HR=4.368, 95%CI: 2.480-7.694, P<0.001) were independent risk factors affecting OS. No neoadjuvant therapy (HR=0.636, 95%CI: 0.413-0.980, P=0.040) and cM1 (HR=5.556, 95%CI: 3.335-9.256, P<0.001) were independent risk factors affecting DFS. pPCN showed a tendency to be an independent risk factor for DFS (HR=1.942, 95%CI: 0.966-3.906, P=0.063). Conclusion:The incidence of pPCN is higher than expected, and the prognosis of patients is poor. Patients with high-risk factors may benefit from extended proximal intestinal resection (>10 cm) to avoid residual positive PCN, thereby reducing local recurrence.

Objective:To analyze the APR triangle formed when the right hepatic vein (RHV) passed through the right anterior hepatic pedicle (RAHP) and the right posterior hepatic pedicle (RPHP) by 3D visualization technique.Methods:Clinical data of 100 subjects undergoing liver contrast-enhanced CT scan in the Second Affiliated Hospital of Harbin Medical University from September 2019 to September 2022 were retrospectively analyzed, including 57 males and 43 females, aged (53.2±13.0) years. The CT data were imported into a system for 3D image reconstruction of the liver. The intrahepatic vascular structure was observed, including the portal vein, APR triangle, the angle between the RAHP and RPHP, the distance between RHV and the vertex of angle when it crosses the angle plane of the RAHP and RPHP, the structure and branches of the right posterior branch of portal vein, and the number of branches into the APR triangle from the main trunk of the right anterior and right posterior portal vein.Results:The main type of portal vein was type A (the main portal vein was divided into left and right branches, and the right branch was further divided into right anterior branch and right posterior branch), in 86 cases (86.0%). The APR triangle was observed in 81 cases (81.0%), and the distance between the right hepatic vein and the vertex of the right anterior and right posterior hepatic pedicle was (1.70±0.36) cm, 1.00-2.00 cm was 82.7%(61/81). The angle between right anterior and right posterior hepatic pedicle was 45°-90° in 77 cases (77.0%, 77/100). In 100 subjects, the main branch of the right posterior portal vein accounted for 42.0% (42/100) of typeⅠ (bifurcation type) and 53.0% (arch type) of type Ⅱ (53/100). In 16 cases (19.8%, 16/81), the main right anterior portal vein branched into the APR triangle, with a total of 22 branches. In 9 cases (11.1%, 9/81), the main branch of the right posterior portal vein (branching type) branched into the triangle, with a total of 11 branches. There were 33 cases (40.7%, 33/81) of right posterior portal vein (arch type) main branch branching into the triangle, a total of 41 branches.Conclusion:The APR triangle, composed of the RAHP, RPHP and RHV, has an objective anatomical basis and is affected by the variants of portal vein and RHV. It is more common for the RHV to be within 1.00-2.00 cm of the vertex of the angle between the RAHP and RPHP, and the main trunk of the right anterior and right posterior branches of portal vein are less divided into the triangle, so it is relatively safe to dissect within this area.

ObjectiveTo investigate the mechanism by which modified Shengjiangsan （MSJS） improves diabetic kidney disease （DKD） by activating mitochondrial autophagy. MethodsSixty SPF-grade male Sprague-Dawley rats aged 7-8 weeks were selected. A DKD model was established using a high-sugar， high-fat diet combined with intraperitoneal injection of streptozotocin （STZ）. After successful modeling， the rats were randomly divided into six groups： a normal control group， a model group， low-， medium-， and high-dose MSJS groups （7.7， 15.4， 30.8 g·kg^-1， respectively）， and an irbesartan group （0.384 g·kg^-1）. Each group received either normal saline or the corresponding drug by gavage once daily for 28 consecutive days. Blood glucose， body weight， and kidney weight were recorded. Serum creatinine （SCr） and blood urea nitrogen （BUN） levels were detected using an automatic blood analyzer. Enzyme-linked immunosorbent assay （ELISA） was used to determine urinary microalbumin （mALB）， and serum levels of tumor necrosis factor-α （TNF-α）， interleukin-1β （IL-1β）， and interleukin-6 （IL-6）. Histopathological changes in renal tissues were observed using hematoxylin-eosin （HE） staining， periodic acid-Schiff （PAS） staining， and transmission electron microscopy （TEM）. The expression levels of mitochondrial autophagy-related proteins in renal tissues were analyzed by Western blot. Immunofluorescence co-localization was employed to detect the co-expression of microtubule-associated protein 1 light chain 3 beta （LC3B） and cytochrome c oxidase subunit Ⅳ （COX Ⅳ）. ResultsCompared with the normal control group， the model group exhibited significant increases in renal index， blood glucose， and 24-hour urinary microalbumin （24 h mALB） （P<0.05， P<0.01）. The levels of serum SCr and BUN were significantly elevated （P<0.01）， and the serum levels of TNF-α， IL-1β， and IL-6 were markedly upregulated （P<0.01）. Histopathological examination revealed glomerular hypertrophy， mesangial expansion and increased deposition， podocyte foot process flattening and fusion， a decreased number of autophagosomes accompanied by mitochondrial swelling， vacuolar degeneration of renal tubular epithelial cells， and inflammatory cell infiltration in the renal interstitium. The expression levels of autophagy-related proteins LC3B， PTEN-induced putative kinase 1 （PINK1）， and E3 ubiquitin-protein ligase （Parkin） were significantly decreased （P<0.05， P<0.01）， while expression of the selective autophagy adaptor protein p62 was significantly increased （P<0.01）. Immunofluorescence signal intensity and LC3B-COX Ⅳ co-expression were both diminished. Compared with the model group， the MSJS treatment groups and the irbesartan group showed significant reductions in renal index， blood glucose， and 24 h mALB （P<0.05， P<0.01）. The serum SCr and BUN levels decreased significantly （P<0.05） and TNF-α， IL-1β， and IL-6 levels were significantly downregulated （P<0.05， P<0.01）. Histopathological damage was alleviated， including reduced glomerular hypertrophy， decreased mesangial deposition， and attenuated podocyte foot process fusion. The number of autophagosomes increased， and mitochondrial swelling was improved. The expression levels of LC3B， PINK1， and Parkin in renal tissues were significantly upregulated， whereas p62 expression was significantly downregulated （P<0.05， P<0.01） in MSJS groups. Immunofluorescence signal intensity was enhanced， and LC3B-COX Ⅳ co-expression was increased. ConclusionMSJS alleviates the inflammatory response in DKD rats and exerts renal protective effects by regulating the PINK1/Parkin signaling pathway and activating mitochondrial autophagy.

ObjectiveTo investigate the mechanism by which modified Shengjiangsan （MSJS） improves diabetic kidney disease （DKD） by activating mitochondrial autophagy. MethodsSixty SPF-grade male Sprague-Dawley rats aged 7-8 weeks were selected. A DKD model was established using a high-sugar， high-fat diet combined with intraperitoneal injection of streptozotocin （STZ）. After successful modeling， the rats were randomly divided into six groups： a normal control group， a model group， low-， medium-， and high-dose MSJS groups （7.7， 15.4， 30.8 g·kg^-1， respectively）， and an irbesartan group （0.384 g·kg^-1）. Each group received either normal saline or the corresponding drug by gavage once daily for 28 consecutive days. Blood glucose， body weight， and kidney weight were recorded. Serum creatinine （SCr） and blood urea nitrogen （BUN） levels were detected using an automatic blood analyzer. Enzyme-linked immunosorbent assay （ELISA） was used to determine urinary microalbumin （mALB）， and serum levels of tumor necrosis factor-α （TNF-α）， interleukin-1β （IL-1β）， and interleukin-6 （IL-6）. Histopathological changes in renal tissues were observed using hematoxylin-eosin （HE） staining， periodic acid-Schiff （PAS） staining， and transmission electron microscopy （TEM）. The expression levels of mitochondrial autophagy-related proteins in renal tissues were analyzed by Western blot. Immunofluorescence co-localization was employed to detect the co-expression of microtubule-associated protein 1 light chain 3 beta （LC3B） and cytochrome c oxidase subunit Ⅳ （COX Ⅳ）. ResultsCompared with the normal control group， the model group exhibited significant increases in renal index， blood glucose， and 24-hour urinary microalbumin （24 h mALB） （P<0.05， P<0.01）. The levels of serum SCr and BUN were significantly elevated （P<0.01）， and the serum levels of TNF-α， IL-1β， and IL-6 were markedly upregulated （P<0.01）. Histopathological examination revealed glomerular hypertrophy， mesangial expansion and increased deposition， podocyte foot process flattening and fusion， a decreased number of autophagosomes accompanied by mitochondrial swelling， vacuolar degeneration of renal tubular epithelial cells， and inflammatory cell infiltration in the renal interstitium. The expression levels of autophagy-related proteins LC3B， PTEN-induced putative kinase 1 （PINK1）， and E3 ubiquitin-protein ligase （Parkin） were significantly decreased （P<0.05， P<0.01）， while expression of the selective autophagy adaptor protein p62 was significantly increased （P<0.01）. Immunofluorescence signal intensity and LC3B-COX Ⅳ co-expression were both diminished. Compared with the model group， the MSJS treatment groups and the irbesartan group showed significant reductions in renal index， blood glucose， and 24 h mALB （P<0.05， P<0.01）. The serum SCr and BUN levels decreased significantly （P<0.05） and TNF-α， IL-1β， and IL-6 levels were significantly downregulated （P<0.05， P<0.01）. Histopathological damage was alleviated， including reduced glomerular hypertrophy， decreased mesangial deposition， and attenuated podocyte foot process fusion. The number of autophagosomes increased， and mitochondrial swelling was improved. The expression levels of LC3B， PINK1， and Parkin in renal tissues were significantly upregulated， whereas p62 expression was significantly downregulated （P<0.05， P<0.01） in MSJS groups. Immunofluorescence signal intensity was enhanced， and LC3B-COX Ⅳ co-expression was increased. ConclusionMSJS alleviates the inflammatory response in DKD rats and exerts renal protective effects by regulating the PINK1/Parkin signaling pathway and activating mitochondrial autophagy.

This study aims to establish a method for counting the viral particles in adenovirus vector-based vaccines. Nano-flow cytometry was employed to analyze the viral particles in adenovirus-based vector vaccines at the single-particle level. Monodisperse silica nanoparticles with a refractive index close to that of the virus were selected as the particle size standard to calculate the viral particle size, which was then compared with the results obtained from transmission electron microscopy (TEM) to determine the gating strategy. Subsequently, a particle count standard was employed to calculate the viral particle concentration. The established method demonstrated good linearity, accuracy, precision, and specificity. The results of determined viral particle concentration showed a good correlation with the infectious titer. Compared with the conventional OD₂₆₀ method, nano-flow cytometry can directly measure the viral particle concentration and indicate whether the sample has been disassembled according to changes in viral particle concentration and size, thus more accurately reflecting the actual infectious potency of the sample. The novel quantification method established in this study is capable of indicating the efficacy of adenovirus vector-based vaccines and provides effective technical support for the quality control of such products.
Adenoviridae/genetics* ; Genetic Vectors ; Flow Cytometry/methods* ; Virion/isolation & purification* ; Particle Size ; Nanoparticles ; Viral Vaccines

Objective:To evaluate the short-term efficacy of minimally invasive treatment of Sanders Ⅱ and Ⅲ calcaneal fractures in diabetes patients using subtalar arthroscopy assisted by preoperative musculoskeletal ultrasound to localize the lateral calcaneal branch of the sural nerve and a medial calcanetalar distractor.Methods:The clinical data of the 52 patients with diabetes mellitus were retrospectively analyzed who had been treated for Sanders Ⅱ and Ⅲ calcaneal fractures from March 2016 to August 2020 at Department of Traumatic Orthopedics, The Third Affiliated Hospital of Soochow University. There were 34 males and 18 females with an age of (61.7±14.5) years. According to the Sanders' classification, there were 23 cases of type Ⅱ and 29 cases of type Ⅲ. Preoperative musculoskeletal ultrasonography was routinely performed to locate the lateral calcaneal branch of the sural nerve in all patients. The surgical procedures were subtalar arthroscopy combined with percutaneous prying reduction and screw fixation assisted by a calcanetalar joint distractor. Incision healing, local skin paraesthesia and other conditions were observed regularly in all patients. The short-term efficacy was assessed by comparing calcaneal lengths, calcaneal widths, calcaneal heights, B?hler angles and Gissane angles at pre-surgery, 3 days, 12 months and the last follow-up after surgery, as well as by comparing visual analogue scale (VAS) pain scores, American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot scores and Maryland scores at pre-surgery, 12 months and the last follow-up after surgery.Results:All the 52 patients were followed up for (23.7±3.2) months after successful surgery. No incision-related complications were reported. The calcaneal radiographic parameters (calcaneal lengths, calcaneal widths, calcaneal heights, B?hler angles and Gissane angles) at 3 days, 12 months and the last follow-up after surgery were significantly improved compared with the values before surgery ( P<0.05), but there were no significant differences regarding the calcaneal radiographic parameters between 3 days, 12 months and the last follow-up after surgery ( P>0.05). The VAS pain scores, AOFAS ankle-hindfoot scores and Maryland scores at 12 months and the last follow-up after surgery were significantly improved compared with those before surgery ( P<0.05). Conclusion:In the minimally invasive treatment of Sanders Ⅱ and Ⅲ calcaneal fractures in diabetes patients, preoperative musculoskeletal ultrasonography to locate the lateral calcaneal branch of the sural nerve, followed by subtalar arthroscopy combined with percutaneous prying reduction and screw fixation assisted by a calcanetalar joint distractor can lead to good short-term efficacy.

Objective:To evaluate the efficacy and safety of immunotherapy combined with chemotherapy as conversion therapy for initially unresectable locally advanced esophageal squamous cell carcinoma.Methods:This retrospective case series study analyzed clinical and pathological data of 32 patients with initially unresectable locally advanced esophageal squamous cell carcinoma who received immunotherapy combined with chemotherapy at the Department of Thoracic Surgery, the Fourth Hospital of Hebei Medical University, from June 2020 to December 2024. The cohort included 27 males and 5 females, with an age ( M(IQR)) of 61(9)years (range:46 to 73 years). Five patients were diagnosed with stage Ⅲ, 27 with stage ⅣA. All patients received PD-1 inhibitor sintilimab combined with nedaplatin and albumin-bound paclitaxel. Radiological evaluations were performed every two cycles, the multidisciplinary team evaluation was conducted to determine conversion to resectable status, and patients with successful conversion underwent radical esophagectomy. Follow-up was conducted via telephone or outpatient visits every 3 to 6 months after the last treatment. The primary endpoint was R0 resection rate, secondary endpoints included objective response rate (ORR), pathological complete response (pCR) rate, major pathological response (MPR) rate, event-free survival (EFS), disease-free survival (DFS) in patients with R0 resection, overall survival (OS) and safety. Kaplan-Meier method was used to plot survival curves and estimate median EFS, DFS, OS rates and their 95% CI. The 95% CI for ORR, pCR rate, MPR rate, and downstaging rate were calculated using the Clopper-Pearson method. Results:The median treatment cycle of 2(1) (range:2 to 8). As of June 2025, the median follow-up was 32.5(13.5)months (range:6.4 to 59.1 months). Among the 32 patients, 9 experienced progression or recurrence, including 2 with liver and lymph node metastases, 2 with lung metastases, 2 with thoracic vertebral metastases, and 3 with mediastinal lymph node metastases. After conversion therapy, 29 patients underwent surgery, achieving an R0 resection rate of 84.4% (95% CI:67.2% to 94.7%), a pCR rate of 27.6% (95% CI:12.7% to 47.2%), and an MPR rate of 55.2% (95% CI:35.7% to 73.6%). Grade 3 or higher surgical complications occurred in 6.9%(2/29) of patients, and grade 3 or higher treatment-related adverse events were observed in 15.6%(5/29). Among the 32 patients, the ORR was 56.3% (95% CI:37.7% to 73.6%),the 3-year EFS rate and OS rate was 59.4% (95% CI:40.8% to 86.4%) and 59.7% (95% CI:40.0% to 89.0%) respectively. Conclusion:Immunotherapy combined with chemotherapy demonstrates high conversion rates and favorable safety in the conversion therapy of initially unresectable locally advanced esophageal squamous cell carcinoma, representing a promising treatment strategy.