Electromagnetic navigation bronchoscopy-guided three-dimensional conformal microwave ablation for unresectable peripheral high-risk pulmonary nodules: a mid-term assessment with no real-time intraoperative CT/cone-beam computed tomography guidance

Introduction

According to the 2025 Global Cancer Statistics (GLOBOCAN), approximately 2,480,000 new lung cancer cases and 1,800,000 lung cancer-related deaths occurred worldwide in 2022 (1). Early diagnosis and timely intervention are central strategies for improving the prognosis of patients with lung cancer. With the widespread implementation of low-dose computed tomography (LDCT) lung-cancer screening globally, pulmonary nodules are being increasingly detected. Approximately 20% of individuals undergoing screening are diagnosed with pulmonary nodules, a considerable proportion of which have malignant potential and are classified as high-risk pulmonary nodules (2).

Currently, radical surgical resection remains the standard treatment for high-risk pulmonary nodules that are highly suspected of malignancy (3). However, in clinical practice, older patients and patients with severe cardiopulmonary dysfunction or multiple comorbidities are often ineligible for or unwilling to receive surgery (4-6). Meanwhile, LDCT screening has a certain false-positive rate, and benign lesions account for 10–30% of surgically resected pulmonary nodules, potentially resulting in unnecessary surgical trauma and irreversible loss of pulmonary function (7). Therefore, the development of precise, minimally invasive, safe, and effective alternative therapeutic strategies is of substantial clinical significance and practical necessity.

Stereotactic body radiation therapy (SBRT) and percutaneous ablation have become important alternative treatments for high-risk pulmonary nodules for those who are unsuitable for or refuse surgery (8). For cases of early-stage lung cancer, SBRT and percutaneous ablation achieve 2-year local control rates of approximately 64.0–69.8%, offering clinically meaningful survival benefits (9-12). Nevertheless, these approaches have important limitations. The incidence of radiation pneumonitis after SBRT is 10–30% (13-19), whereas percutaneous ablation is associated with substantial risks of pneumothorax (21.1–63.0%) (20,21) and hemorrhage (0–10.0%) (22). Therefore, precise ablation path planning and complete conformal coverage of target lesions remain urgent clinical challenges.

Electromagnetic navigation bronchoscopy (ENB), which is based on electromagnetic positioning, virtual bronchoscopy, and high-resolution computed tomography (CT)-based three-dimensional reconstruction, enables preoperative path planning and accurate access to peripheral pulmonary nodules through the natural airway, with a navigation accuracy of 2–5 mm for peripheral lesions (23,24). This technique can significantly reduce the risk of complications related to percutaneous puncture and is compatible with biopsy, localization, ablation, and other interventional procedures, suggesting its broad clinical application potential (25-28). Microwave ablation (MWA), a mature thermal ablation technique, induces rapid temperature elevation (60–100 ℃) in target tissues and achieves coagulative necrosis via thermal effects, representing a mainstream modality for the local treatment of lung tumors (24). ENB-guided MWA for high-risk pulmonary nodules has become an active area of investigation, and existing studies have provided preliminary evidence of its feasibility and safety (29,30). However, current evidence remains insufficient: most studies have focused on nodules with a positive bronchus sign and lesions located away from the pleura and blood vessels; conventional single-probe ablation often cannot adequately achieve conformal coverage for irregular nodules; and to date, large-scale and standardized clinical evidence for electromagnetic navigation-guided three-dimensional conformal microwave ablation (ENB-DCMA) remains limited.

Our center developed an innovative ENB-DCMA platform to achieve precise and conformal ablation of high-risk pulmonary nodules through preoperative three-dimensional reconstruction, multi-target localization, and individualized ablation parameter optimization. In this retrospective study, we analyzed the clinical data of patients receiving ENB-DCMA treatment, aiming to evaluate its mid-term efficacy and safety and provide evidence for standardized clinical application. We present this article in accordance with the STROBE reporting checklist (available at https://tlcr.amegroups.com/article/view/10.21037/tlcr-2026-0545/rc).

Methods

Study design and patient enrollment

This single-center retrospective observational study consecutively recruited patients with peripheral high-risk pulmonary nodules who received ENB-DCMA treatment at the Thoracic Oncology Department of Sun Yat-sen University Cancer Center between March 2021 and August 2023. After August 2023, our center upgraded the technical workflow by adding cone-beam computed tomography (CBCT) intraoperative confirmation. To ensure internal methodological consistency and avoid technical heterogeneity, only patients treated with the original standardized protocol within this time interval were included; relevant outcomes of the optimized scheme will be reported in our subsequent research. Preoperative evaluations included general clinical status, medical history, laboratory tests, and chest CT imaging. All patients were discussed and managed through multidisciplinary team (MDT) consultations involving thoracic surgeons, radiologists, and oncologists. The study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. The study was approved by the Ethics Committee of Sun Yat-sen University Cancer Center (No. B2025-398-01), and written informed consent was obtained from all patients.

Inclusion criteria

The inclusion criteria were as follows: (I) peripheral pulmonary nodules confirmed by chest CT with maximum diameter ≤3 cm; (II) nodule enlargement or increased solid component proportion during imaging follow-up; (III) nodules considered highly suspicious for malignancy based on joint assessment by thoracic surgeons, radiologists and oncologists; (IV) patients who provided informed consent for ENB-DCMA due to surgical and radiotherapy ineligibility or declination; and (V) complete clinical data and follow-up duration of no less than 12 months.

Exclusion criteria

The exclusion criteria included the following: (I) contraindications to general anesthesia or bronchoscopy; (II) an uncorrectable bleeding tendency or severe coagulopathy (e.g., platelet count <60×10⁹/L); (III) severe underlying diseases including uremia, severe pulmonary hypertension, intracranial hypertension, aortic dissection and systemic organ failure; (IV) women who were pregnant or lactating; (V) uncontrolled malignant tumors in other organs; and (VI) incomplete clinical data or loss to follow-up.

ENB-DCMA procedure

All patients underwent thin-slice chest CT (1.0–1.25 mm) within 2 months before ablation. Digital Imaging and Communications in Medicine (DICOM) data were imported into the ENB system workstation (SuperDimension™ V7.0, Medtronic, USA) for three-dimensional reconstruction, target marking, and path planning, with operator optimization. Ablation parameters were preset according to nodule density and size to ensure a 360° coverage of the target nodule. During preoperative planning, the target nodule was stratified into three distinct ablative zones for navigation planning: Zone 1 targeted the physical center of the lesion, Zone 2 targeted the portion of the lesion in closest proximity to the airway, and Zone 3 targeted the area farthest from the airway. Furthermore, depending on the lesion density, location, and size, as well as the empirically estimated displacement caused by respiratory motion, additional ablative zones were judiciously added to ensure maximal spatial coverage of the target nodule. After the pre-bent extended working catheter was navigated to the vicinity of the nodule under electromagnetic guidance, the catheter was rotated to align with these predefined targets, thereby positioning the probe at the optimal ablative angle for each zone.

After general anesthesia, the patients were positioned supine. A bronchoscope (EB-580T; Fujifilm, Japan) was used to examine the airways. A locatable guide (LG) was inserted through the extended working channel (EWC) and registered. Under navigation guidance, the LG was advanced to the target lesion and then withdrawn. A radial endobronchial ultrasound (rEBUS) probe (SP 900, Fujifilm, Japan) was inserted to confirm the lesion using 360° scanning. After the bronchoscope was fixed in position, biopsy, brushing, and bronchoalveolar lavage (BAL) were performed sequentially, with the specimens sent for rapid on-site evaluation (ROSE) and cytological examination. A flexible microwave ablation probe (ECO-100A115; Vison Medical, Nanjing, China) was inserted through the EWC. Ablation was performed at 25–35 W for 4–8 min, with 2–3 cycles per target, and vital signs were monitored continuously.

For nodules without a bronchus sign, bronchoscopic transparenchymal nodule access (BTPNA; also known as the “tunnel technique”) was used (31). Under navigation guidance, a point of entry (POE) was selected to avoid large blood vessels and bronchi. A puncture needle (NA-403D-2021, Olympus, Japan) penetrated the airway wall, and the tract was gradually dilated with forceps. Biopsy and ablation were completed through the transparenchymal tract under real-time ENB guidance.

Follow-up

Chest CT was performed within 24 h after ablation to evaluate early post-ablation changes and immediate complications. Chest CT was repeated at 1, 3, 6, 9, and 12 months after ablation, every 6 months in years 2 and 3, and annually thereafter. Additional CT or chest radiography was performed if the patients presented with chest discomfort, hemoptysis, fever, or other symptoms. Chest CT at 1 month after ablation served as the baseline for subsequent comparative analysis of changes in the size, density, and morphology of the ablation zone.

Safety and efficacy evaluation

Adverse events occurring during or within 30 days of ablation were recorded and graded using the Common Terminology Criteria for Adverse Events (CTCAE) Version 6.0 (32). Safety was assessed using this grading system.

The primary efficacy endpoint was defined as local progression-free survival (LPFS), with local progression judged by lesion enlargement, increased solid component or new abnormal lesions within the ablation area. Local control was defined as no radiological progression, including no enlargement, no increase in the solid component, or no new lesions within the ablation zone during follow-up. The technical success rate was defined as the complete execution of ablation strictly in accordance with the preoperative protocol, accompanied by postoperative 24-hour chest CT confirmation that the ablation zone fully covered the target lesion and reached the predefined safe ablation margin. All evaluations were performed independently by two senior radiologists in a blinded manner.

Statistical analysis

Continuous variables were expressed as mean ± standard deviation (SD) or median [interquartile range (IQR)] and compared using Student’s t-test or Mann-Whitney U test. Categorical variables were expressed as n (%) and compared using the χ² test or Fisher’s exact test. Survival curves were generated using the Kaplan-Meier method, and differences were compared using the log-rank test. Results are presented using hazard ratios (HR) and 95% confidence intervals (CIs). P<0.05 was considered statistically significant. Statistical analyses were performed using SPSS 31.0 (IBM Corp., Armonk, NY, USA).

Notably, some patients had multiple pulmonary nodules included in the present cohort. To satisfy the statistical independence assumption and minimize intra-patient correlation bias, per-nodule analysis was performed with adjustment for clustering effects within the same individual. Each eligible nodule was defined as the primary observational unit; statistical analyses appropriately accounted for repeated lesions from a single patient to avoid the overestimation of clinical efficacy and complication rates.

Results

Baseline characteristics of patients and lesions

Fifty patients with 62 peripheral high-risk pulmonary nodules, treated with ENB-DCMA, were enrolled. The technical workflow is shown in Figure 1, and a representative ENB-DCMA procedure is presented in Figure 2. The cohort included 19 (38.0%) men and 31 (62.0%) women, with a mean age of 62.08±12.65 years. Among them, 26/50 (52.0%) patients were aged ≥65 years. Solitary high-risk pulmonary nodules were found in 40 (80.0%) patients, whereas 2 nodules were found in 8 (16.0%) patients and 3 nodules in 2 (4.0%) patients. Two patients underwent simultaneous surgical resection with ENB-DCMA. Both patients were highly suspected to have malignant nodules based on systematic preoperative imaging evaluation and MDT consultation, while surgical assessment confirmed that they could not tolerate the complete combined resection of multiple pulmonary segments or lobes. All patients underwent MDT review before treatment to ensure an individualized therapeutic strategy. Comorbidities and medical history included a history of cancer in 30 (60.0%) patients, previous surgery in 27 (54.0%) patients, chronic obstructive pulmonary disease (COPD) in 9 (18.0%) patients, diabetes mellitus in 6 (12.0%) patients, hypertension in 10 (20.0%) patients, and hyperthyroidism in 1 (2.0%) patient. Baseline characteristics and treatment features are summarized in Table 1.

Figure 1 Technical route flowchart. BTPNA, bronchoscopic transparenchymal nodule access; CT, computed tomography; ENB, electromagnetic navigation bronchoscopy; rEBUS, radial endobronchial ultrasound.

Figure 2 ENB-DCMA specific procedures. (A) Chest CT prior to ENB-DCMA, the arrow indicates the original lesion site. (B) Zone 2: the portion of the lesion in closest proximity to the airway. (C) Zone 1: the physical center of the lesion. (D) Zone 3: the area of the lesion farthest from the airway. (E) A three-dimensional targeting method is adopted to ensure the catheter reaches zone 1, zone 2 and zone 3 thereby confirming pathological sampling and adequate ablation range. (F) Prebent catheter. CT, computed tomography; ENB-DCMA, electromagnetic navigation-guided three-dimensional conformal microwave ablation.

The radiological features and ablation parameters of the 62 nodules are presented in Table 2. BTPNA was used for 14 nodules (Figure 3). The median nodule diameter was 11.0 (IQR, 7.0–16.0) mm, and the median distance to the pleural surface was 16.6 (IQR, 10.3–30.1) mm. Regarding location, 30 (48.4%) nodules were in the peripheral zone, 20 (32.3%) in the middle zone, and 12 (19.4%) in the proximal zone. The lobar distribution included 15 (24.2%) nodules in the left upper lobe, 9 (14.5%) in the left lower lobe, 18 (29.0%) in the right upper lobe, 5 (8.1%) in the right middle lobe, and 15 (24.2%) in the right lower lobe. The bronchus sign was positive in 27 (43.5%) nodules and negative in 35 (56.5%). All nodules were biopsied before treatment. Histopathological results showed atypical hyperplasia/precancerous lesions in 9 (14.5%) nodules, adenocarcinoma in situ/minimally invasive adenocarcinoma in 2 (3.2%) nodules, and invasive adenocarcinoma in 14 (22.6%) nodules. The overall proportion of malignant and precancerous lesions was 40.3% (25/62), and 37 (59.7%) nodules were pathologically negative. The ablation power was 25 W in 27 (43.5%) nodules, 30 W in 24 (38.7%), and 35 W in 11 (17.7%). The median ablation time was 17.5 (10.0–23.0) min.

Figure 3 BTPNA technique. (A) Chest CT prior to ENB-DCMA, the arrow indicates the original lesion site. (B) Target nodule path planning. (C) Intraoperative real-time navigation map. (D) POE procedure. (E) Reexamination 1 day after surgery. BTPNA, bronchoscopic transparenchymal nodule access; CT, computed tomography; ENB-DCMA, electromagnetic navigation-guided three-dimensional conformal microwave ablation; POE, point of entry.

Safety analysis of ENB-DCMA

In total, 50 patients with 62 eligible pulmonary nodules were included, with 65 ablation procedures performed in total, including repeated ablation for three lesions. The technical success rate of this procedure was 95.2%. The median post-ablation hospital stay was 2.65 (IQR, 1.70–3.80) days. The overall complication rate was 18.0% (9/50), and all events were classified as CTCAE grade 1 or 2. The most frequent complication was pneumothorax, which occurred in 6 (12.0%) patients: 4 (8.0%) had grade 1 pneumothorax with asymptomatic or mild symptoms requiring observation only, whereas 2 (4.0%) had grade 2 pneumothorax requiring drainage. Pulmonary hemorrhage was documented in 2 (4.0%) patients, both categorized as grade 1 and self-limiting, with no intervention required. One (2.0%) patient developed transient low-grade fever (grade 1), which resolved spontaneously within 24 h. No grade ≥3 complications, including massive hemorrhage, organ failure, or procedure-related mortality, occurred (Table 3).

Efficacy analysis of ENB-DCMA

The follow-up cutoff date was July 29, 2026. All 50 enrolled patients completed at least 12 months of follow-up. Among these patients, 42 patients finished 24-month follow-up, and 25 patients completed 36-month follow-up. The median follow-up was 37.1 (range, 14.7–59.9) months. The median LPFS was not reached, and the 36-month LPFS rate was 82.3%. Stratified by nodule type, the median LPFS was not reached for sub-solid nodules, with a 36-month LPFS rate of 95.8%. For solid nodules, the median LPFS was 10.4 (95% CI: 10.0–10.8) months, and the 36-month LPFS rate was 35.7%. Sub-solid nodules had a significantly lower risk of local progression than solid nodules (HR =0.04, 95% CI: 0.01–0.21, P<0.001). Stratified by nodule size, median LPFS was not reached in either the <20 mm group or the 20–30 mm group. The 36-month LPFS rates were 86.3% and 63.6%, respectively, with no significant difference between the two groups (HR =0.31, 95% CI: 0.09–1.04, P=0.059). Stratified by pathological type, LPFS rates for pathological confirmed malignant nodules and pathological negative/premalignant nodules at 36 months were 68.8% and 87.0%, respectively, with no significant difference between the two groups (HR =0.37, 95% CI: 0.11–1.21, P=0.10) (Figures 4-6).

Figure 4 Subgroup analysis of solid nodules with sub-solid nodules. CI, confidence interval; HR, hazard ratio; LPFS, local progression-free survival.

Figure 5 Subgroup analysis of lesions <2 and 2–3 cm in size. CI, confidence interval; HR, hazard ratio; LPFS, local progression-free survival.

Figure 6 Subgroup analysis based on pathological diagnosis (malignant and negative/premalignant). CI, confidence interval; HR, hazard ratio; LPFS, local progression-free survival.

Dynamic follow-up showed that all local progression events occurred within 12 months after ablation. Sub-solid nodules maintained a high local control rate: 97.9% at 6 months and 95.8% at 12 months. By contrast, solid nodules showed a marked decline in local control: 71.4% at 6 months and only 35.7% at 12 months (Figure 7).

Figure 7 The local control rates of solid nodules and sub-solid nodules at 6 and 12 months. (A) Local control rate of sub-solid nodules at 6 and 12 months. (B) Local control rate of solid nodules at 6 and 12 months. Blue bars indicate local control, and red bars indicate local progression.

Discussion

This study integrated electromagnetic navigation, three-dimensional reconstruction, multi-target localization, and conformal microwave ablation into a single platform for high-risk pulmonary nodules and demonstrated favorable local control and safety. ENB-DCMA provides an efficient, minimally invasive, and integrated therapeutic strategy for patients with high-risk pulmonary nodules who are not candidates for surgery or who decline surgery. Furthermore, the three-dimensional conformal planning using a pre-bent introducing sheath and controlled rotational adjustments of the ablation probe may generate a deliberately expanded ablation volume. This strategy robustly compensates for respiratory motion-induced target displacement and mitigates the risk of geographic miss, particularly in centers lacking intraoperative volumetric CT verification (e.g., CBCT).

The safety advantages of ENB-DCMA are evident from three key aspects. First, ENB-DCMA accesses the target nodules through the natural airway without transpleural puncture, reducing the risk of pneumothorax, hemothorax, and other puncture-related complications. Second, preoperative high-resolution CT three-dimensional reconstruction combined with electromagnetic navigation enables precise localization and path planning, helps avoid critical anatomical structures, including large blood vessels and bronchial bifurcations, and minimizes mechanical injury to the adjacent normal tissues. Third, the three-dimensional conformal ablation strategy, based on multi-target marking and individualized parameter planning, enables complete target-lesion coverage. This approach may reduce residual disease due to insufficient ablation and limit thermal injury to the surrounding lung parenchyma, potentially lowering the risk of post-ablation pneumonia and long-term pulmonary function impairment.

A meta-analysis of 53 studies reported pneumothorax rates of 34.3% and 33.9% after percutaneous radiofrequency ablation and microwave ablation, respectively, with 12.3% and 11.0% of patients requiring clinical intervention (33). For nodules adjacent to the pleura or large blood vessels, percutaneous puncture may further increase the risk of severe hemorrhage or hemopneumothorax. In the present study, pneumothorax occurred in 12.0% (6/50) of the patients, and only 4.0% (2/50) required intervention, indicating a favorable safety profile compared with percutaneous ablation. SBRT is a noninvasive alternative for medically inoperable early-stage lung cancer but is associated with a 10–30% risk of radiation pneumonitis, which can cause irreversible pulmonary function impairment and reduce quality of life in severe cases (34,35). In addition, SBRT usually requires multiple fractions and prolonged treatment. By contrast, ENB-DCMA allows combined biopsy and ablation in a single procedure, with a median post-ablation hospital stay of 2.65 days; most patients were discharged within 2–3 days, reducing healthcare burden and improving treatment acceptability.

SBRT has been recognized as the standard treatment for medically inoperable early lung cancer, with a reported 3-year local control rate of 77.9–88% (36-38). Percutaneous thermal ablation is also widely used as a minimally invasive option. In a study of 669 malignant pulmonary tumors treated with percutaneous microwave ablation, Geevarghese et al. (39) reported 1- and 2-year local control rates of 90.3% and 84.7%, respectively. A recent multicenter trial (BRONC-RFII) of transbronchial radiofrequency ablation showed a 1-year intrapulmonary progression-free survival rate of 88.89% (40). The risk of local progression was significantly higher in solid nodules than in sub-solid nodules (HR =5.95, 95% CI: 2.04–17.33, P<0.001), whereas no significant difference was observed between nodules <20 and 20–30 mm. Bao et al. (29) and Chan et al. (30,41) also showed that early lung cancer presenting as sub-solid nodules achieved nearly 100% local control after ENB-guided ablation with low complication rates, although these studies were limited by their small sample sizes and short follow-up.

This study extended follow-up and included mature survival endpoints, with a median follow-up of 37.1 (range, 14.7–59.9) months. The overall 3-year LPFS reached 82.3%, increasing to 95.8% for sub-solid nodules. These results provide real-world evidence of the durable efficacy of ENB-DCMA for peripheral high-risk pulmonary nodules.

In this study, 59.7% (37/62) lesions yielded negative malignant results on transbronchial biopsy; apart from intrinsic lesion characteristics, this result may also be attributed to the inherent technical limitations of transairway sampling (42), which is fundamentally distinct from definitive histopathological diagnosis based on surgically resected specimens. To further explore the prognostic value of pathological results for mid-term clinical outcomes, we conducted a stratified survival analysis according to final biopsy diagnoses, revealing that the 36-month LPFS rates were 68.8% for pathologically confirmed malignant nodules and 87.0% for pathologically negative and premalignant nodules; although the Kaplan-Meier curves demonstrated a visible divergent trend between the two groups, the difference did not reach statistical significance (HR =0.37, 95% CI: 0.11–1.21, P=0.100). These findings suggest that ENB-DCMA is a safe and feasible radical local therapeutic strategy for high-risk pulmonary nodules with strong radiological suspicion of malignancy. Nevertheless, we fully recognize the diagnostic uncertainty of transbronchial biopsy. For high-risk nodules that cannot be definitively diagnosed via airway sampling, ablation decision-making should be performed within a standardized MDT framework, wherein clinical judgment integrates comprehensive radiological evidence, including nodule size, dynamic changes in solid components, and longitudinal growth trends during follow-up, to prudently determine the necessity of ablation. Furthermore, before ablation, patients should be fully informed of the inherent uncertainty of biopsy-based pathological results and the necessity of long-term rigorous postoperative surveillance, thereby ensuring standardized clinical decision-making and optimal patient safety.

In total, 14 high-risk solid pulmonary nodules were included herein, 12 of which were clinically highly suspicious of pulmonary oligometastases, consisting of 7 lesions metastatic from colorectal cancer, 3 from primary lung cancer and 2 from thyroid cancer. Considering that the local intervention strategy for such metastatic pulmonary nodules needs to be formulated based on the primary tumor burden and subsequent systematic systemic treatment regimens, the results of this exploratory study suggest that microwave ablation monotherapy achieves suboptimal efficacy for pulmonary metastatic lesions. Future studies can explore comprehensive “ablation + X” strategies combining ablation with chemotherapy, targeted therapy or immunotherapy to achieve better control of tumor progression (43-45).

Nonetheless, this study has some limitations. First, it was a single-center retrospective study with limited sample size, and the statistical power of the subgroup analysis for solid nodules was insufficient. Second, the study lacked a randomized control group and head-to-head comparisons with percutaneous ablation or SBRT, precluding direct quantification of the relative advantages of ENB-DCMA. Third, the follow-up was less than 5 years; therefore, long-term efficacy and late recurrence risk, particularly for sub-solid nodules, require validation through longer follow-up.

Conclusions

ENB-DCMA incorporating an enlarged conformal ablative margin demonstrated favorable mid-term efficacy and safety as a notable strategy for peripheral pulmonary nodules. Particularly encouraging results were noted for patients with sub-solid lesions, achieving a 3-year LPFS rate of 95.8%. Nevertheless, further multicenter prospective trials are warranted to validate these findings and assess long-term oncologic outcomes.

Acknowledgments

None.

Footnote

Reporting Checklist: The authors have completed the STROBE reporting checklist. Available at https://tlcr.amegroups.com/article/view/10.21037/tlcr-2026-0545/rc

Data Sharing Statement: Available at https://tlcr.amegroups.com/article/view/10.21037/tlcr-2026-0545/dss

Peer Review File: Available at https://tlcr.amegroups.com/article/view/10.21037/tlcr-2026-0545/prf

Funding: This work was supported by the Guangdong Esophageal Cancer Institute, Guangzhou (No. M202310).

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://tlcr.amegroups.com/article/view/10.21037/tlcr-2026-0545/coif). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. The study was approved by the Ethics Committee of Sun Yat-sen University Cancer Center (No. B2025-398-01), and written informed consent was obtained from all patients.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

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