Recurrent Laryngeal Nerve Lymph Node Research Articles

Comparisons of short-term outcomes between robot-assisted, video-assisted, and open esophagectomy for resectable esophageal cancer after neoadjuvant treatment: a retrospective study.

Robot-assisted esophagectomy (RAE), video-assisted minimally invasive esophagectomy (VAMIE), and open esophagectomy (OE) all have significant roles in the management of esophageal cancer (EC). Few studies have compared efficacy and safety between RAE, VAMIE, and OE for resectable EC after neoadjuvant treatment. Therefore, this study aimed to explore the short-term outcomes between RAE, VAMIE, and OE for resectable EC after neoadjuvant treatment. Ninety-eight patients were consecutively enrolled who underwent esophagectomy. A retrospective study was performed including 98 consecutive patients treated from January 2021 to August 2022 who received neoadjuvant treatment (including immunochemotherapy and chemoradiotherapy) followed by RAE, VAMIE or OE. Evaluated endpoints in the present study consisted of pathological outcomes, intraoperative and postoperative outcomes, as well as postoperative complications. No significant differences were seen in the operating time, blood loss, length of intensive care unit (ICU) stay, R0 resection, and number of dissected lymph nodes between the three RAE, VAMIE, or OE groups. The achievement rate of right recurrent laryngeal nerve (RLN) lymph node removal (P=0.01) and the total cost (P<0.001) were higher in RAE. The postoperative hospital stay of OE was longer than the other two groups (P<0.05). There were no significant differences in postoperative complications. Compared to VAMIE, no clear benefit exists for RAE in the treatment of resectable EC after neoadjuvant therapy. OE resulted in a longer hospital stay. Although the rate of successful right RLN node removal was higher with RAE, the clinical relevance for this is yet unclear.

196. MINIMALLY INVASIVE ESOPHAGECTOMY WITH AWARENESS OF THE THIN MEMBRANOUS DENSE CONNECTIVE TISSUES AROUND THE ESOPHAGUS

Abstract Background We have clinically introduced the ‘mediastinoscopic esophagectomy with lymph node dissection’ (MELD) to esophagectomy for thoracic esophageal cancer, performed under pneumomediastinum via trans-bicervical and transhiatal approach since 2014. In parallel with this, we have been conducting histological studies of the thin membranous dense connective tissue (TMDCT) around the esophagus and utilizing the results during these surgeries to ensure a rational esophagectomy. Here, we describe the differences in the visibility of TMDCT between the two approaches for esophagectomy. Methods We retrospectively examined the visibility of TMDCT in surgical videos of trans-mediastinnal and trans-right thoracic approaches after 2015 to determine the characteristics of each approaches. Results The trans-mediastinal approach reaches the visceral sheath by entering just dorsal to the esophagus in the right neck, and the TMDCT is seen in a bubbled appearance. Unlike the right thoracic approach, the visceral sheath can be easily reached without a pleural incision. The adipose tissue including lymph nodes around the left recurrent laryngeal nerve (RLN) showed a clear dissection layer between the left subclavian artery, but the boundary between the lymph nodes around the left RLN and the aorta was unclear near the aortic arch, which was thought to be due to the lack of visceral sheath around No.106tbL. On the other hand, the trans-right thoracic approach showed a slightly shiny visceral sheath covering the surface of the thoracic duct on the dorsal side of the esophagus. In the left superior mediastinum, the left RLN and RLN lymph nodes were located on the organ side of the visceral sheath covering the esophagus and trachea. In right and left sides, the visceral sheath was obscured near the branch of the RLN from the vagus nerve, but the RLNs ran cranially on the medial side of the visceral sheaths. Conclusion We reported how the TMDCT is visualized with each surgical approach. The visceral sheath was visualized as a bubbly structure in the trans- mediastinal approach and as a slightly shiny areal structure in the trans-right thoracic approach. Recognition of the TMDCT around the esophagus was useful for safe and rational lymph nodes dissection regardless of the surgical approach.

150. PATTERN OF LYMPH NODE RECURRENCE AFTER NEOADJUVANT CHEMORADIOTHERAPY AND MODIFIED EN BLOC ESOPHAGECTOMY

Abstract Background Esophageal cancer is an aggressive malignancy with high incidence of lymph node metastasis and recurrence rate even after neoadjuvant treatment and radical resection. Previous study has shown that modified en bloc esophagectomy (mEBE) improves survival for esophageal squamous cell carcinoma (ESCC) after neoadjuvant chemoradiotherapy (nCRT). In this study, we aim to investigate the pattern of lymph node recurrence after nCRT+mEBE. Methods The data of patients who received nCRT followed by curative surgical resection for ESCC were retrospectively reviewed. The mEBE includes ‘mesophagus’ dissection and bilateral recurrent laryngeal nerve node dissection, whereas conventional esophagectomy (CE) only requires periesophageal tissues dissection that were close to the esophagus. The pattern of recurrence, especially lymph node recurrence (cervical, upper mediastinum, infra-carina, and abdominal), were compared between CE and mEBE, with stratification according to pathological stage (ypT0N0 or not.) Results A total of 221 (CE, n = 181; mEBE, n = 40) patients were included. Mediastinal lymph node recurrence was noted in 16.0% and 7.5% of patients after CE and mEBE, respectively (p = 0.166). In ypT0N0 patients who received CE, 6.0% had upper mediastinum recurrence, whereas no mediastinal recurrence was noted after mEBE (p = 0.329). In non-ypT0N0 stage patients who received CE, 15.3% and 8.2% had upper mediastinum and infra-carina recurrences, compared to 12.0% and 0% after mEBE (p = 0.283). There cervical/abdominal recurrences were noted in 6.6%/7.2% and 15.0%/5.0% after CE and mEBE, respectively (p = 0.080/0.618). Conclusion Although there was no significant difference in lymph node recurrence pattern between mEBE and CE, we observed that (1) 6% of ypT0N0 patients developed mediastinal lymph node recurrence after CE, implying the possibility of understaging after CE; (2) no patients developed infra-carina lymph node recurrence after mEBE, suggesting the necessity of mesoesophagus dissection, and (3) high incidence of cervical lymph node recurrence even after mEBE, indicating that cervical dissection should be considered in selected patients.

Characteristics of lymph node metastasis of right recurrent laryngeal nerve in thoracic esophageal squamous cell carcinoma

Objective: To understand the characteristics and influencing factors of lymph node metastasis of the right recurrent laryngeal nerve in thoracic esophageal squamous cell carcinoma (ESCC), and to explore the reasonable range of lymph node dissection and the value of right recurrent laryngeal nerve lymph node dissection. Methods: The clinicopathological data with thoracic ESCC were retrospectively analyzed, and the characteristics of lymph node metastasis along the right recurrent laryngeal nerve and its influencing factors were explored. Results: Eighty out of 516 patients had lymph node metastasis along the right recurrent laryngeal nerve, the metastasis rate was 15.5%. Among 80 patients with lymph node metastasis along the right recurrent laryngeal nerve, 25 cases had isolated metastasis to the right recurrent laryngeal nerve lymph node but no other lymph nodes. The incidence of isolated metastasis to the recurrent laryngeal nerve lymph node was 4.8% (25/516). A total of 1 127 lymph nodes along the right recurrent laryngeal nerve were dissected, 115 lymph nodes had metastasis, and the degree of lymph node metastasis was 10.2%. T stage, degree of tumor differentiation and tumor location were associated with right paraglottic nerve lymph node metastasis (all P<0.05). The lymph node metastasis rate along the right recurrent laryngeal in patients with upper thoracic squamous cell carcinoma (23.4%, 26/111) was higher than that of patients with middle (13.5%, 40/296) and lower (12.8%, 14/109) thoracic squamous cell carcinoma (P=0.033). In patients with poorly differentiated ESCC (20.6%, 37/180) the metastasis rate was higher than that of patients with moderately (14.6%, 39/267) and well-differentiated (5.8%, 4/69; P<0.05). The lymph node metastasis rate of patients with stage T4 (27.3%, 3/11) was higher than that of patients with stage T1 (9.6%, 19/198), T2 (19.0%, 16/84) and T3 (18.8%, 42/1 223; P<0.05). Multivariate regression analysis showed that tumor location (OR=0.61, 95% CI: 0.41-0.90, P=0.013), invasion depth (OR=1.46, 95% CI: 1.11-1.92, P=0.007), and differentiation degree (OR=1.67, 95% CI: 1.13-2.49, P=0.011) were independent risk factors for lymph node metastasis along right recurrent laryngeal nerve of ESCC. Conclusions: The lymph node along the right recurrent laryngeal nerve has a higher rate of metastasis and should be routinely dissected in patients with ESCC. Tumor location, tumor invasion depth, and differentiation degree are risk factors for lymph node metastasis along right recurrent laryngeal nerve in patients with ESCC.

Impact of the Extent of Recurrent Laryngeal Nerve Lymphadenectomy on Thoracic Esophageal Squamous Cell Carcinoma: A Real-World Multicenter Study.

To determine the impact of recurrent laryngeal nerve lymph node (RLN-LN) dissection on survival and postoperative complications in patients with oesophageal squamous cell carcinoma (ESCC). Patients with cT1-4N0-3M0 thoracic ESCC who underwent oesophagectomy and two-field lymphadenectomy from three institutions were included. The entire cohort was divided into three groups that underwent the total two-field lymphadenectomy (T-2FL), standard two-field lymphadenectomy (S-2FL), or unilateral RLN-LN dissection plus S-2FL (U-2FL) based on the extent of RLN-LN dissection. Subgroup analyses were also performed and were stratified by treatment modality. Both the U-2FL and T-2FL groups had significantly superior outcomes compared with the S-2FL group (overall survival: U-2FL vs S-2FL: P = 0.002; T-2FL vs S-2FL: P < 0.001; recurrence-free survival: U-2FL vs S-2FL: P = 0.01; T-2FL vs S-2FL: P < 0.001). Moreover, no significant differences were observed between U-2FL and T-2FL regarding overall survival (P > 0.05) and recurrence-free survival (P > 0.05), irrespective of administration of neoadjuvant therapy plus oesophagectomy or upfront oesophagectomy. Additionally, the extent of RLN-LN dissection was not an independent predictor of stage migration (P = 0.14), but was for postoperative nodal upstaging (P = 0.02). Notably, S-2FL brought significantly lowered risk in postoperative complications, especially for RLN palsy, when compared with T-2FL (P = 0.002) but not U-2FL (P = 0.72). Adequacy of RLN-LN dissection is an important prognosticator for improved overall survival and recurrence-free survival in patients with thoracic ESCC. U-2FL may serve as an alternative to T-2FL in selected populations.

Learning Curve of Robot-Assisted Lymph Node Dissection of the Left Recurrent Laryngeal Nerve: A Retrospective Study of 417 Patients.

Left recurrent laryngeal nerve (no.106recL) lymph node dissection is a challenging procedure, and robotic-assisted minimally invasive esophagectomy (RAMIE) may have some advantages. This study aimed to determine the learning curve of no.106recL lymph node dissection. The data of 417 patients who underwent McKeown RAMIE between June 2017 and June 2022 were retrospectively analyzed. The lymph node harvest of no.106recL was used to determine the learning curve, and the cumulative sum (CUSUM) method was employed to obtain the inflection point. A total of 404 patients (404/417, 96.9%) underwent robotic surgery. Based on the number of no.106recL lymph nodes harvested, the CUSUM learning curve was mapped and divided into three phases: phase I (1‒75 cases), phase II (76‒240 cases), and phase III (241‒404 cases). The median (IQR) number of no.106recL lymph node harvests were 1 (4), 3 (6,) and 4 (4) in each phase (p < 0.001). The lymph node dissection rate gradually increased from 62.7% in phase I to 82.9% in phase III (p = 0.001). The total and thoracic lymph node harvest gradually increased (p < 0.001), whereas operation time (p = 0.001) and blood loss gradually decreased (p < 0.001). Moreover, the incidence of total complication (p = 0.020) and recurrent laryngeal nerve injury (p = 0.001) significantly decreased, and the postoperative hospital stay gradually shortened (p < 0.001). Robotic no.106recL lymph node dissection has some advantages for patients with esophageal cancer. In this study, perioperative and clinical outcomes were significantly improved over the learning curve. However, further prospective studies are required to confirm our results.

Stratification of lymph node metastasis improves diagnostic efficiency in thoracic esophageal squamous cell carcinoma.

Difference of the short diameter of lymph nodes in the main regions of esophageal squamous cell carcinoma (ESCC) and its value in the diagnosis of lymph nodes need to explore. The clinical data of patients with thoracic ESCC who underwent surgical treatment in our hospital were collected. The short diameters of the largest lymph node in each region of the patient were measured by preoperative enhanced computed tomography (CT) and were compared with the postoperative pathology. A total of 477 patients with thoracic ESCC who did not receive neoadjuvant therapy were enrolled in this study. The receiver operating characteristic curve suggested that the short diameters of the paracardial nodes, the left gastric nodes, the right recurrent laryngeal nerve nodes, and the left recurrent laryngeal nerve nodes could well predict the postoperative pathology of the lymph nodes, with area under curve (AUC) of 0.958, 0.937, 0.931, and 0.915, the corresponding cut-off values of 5.7mm, 5.7mm, 5.5mm, and 4.8mm, the corresponding sensitivities of 94.7%, 85.4%, 88.7%, and 79.4%, and the corresponding specificities of 93.7%, 96.3%, 86.2%, and 95.0%, respectively. The AUC of the thoracic paraesophageal lymph nodes, the subcarinal nodes and all regional lymph nodes were 0.845, 0.688, and 0.776, respectively. Region-based criterion for lymph node metastasis of thoracic ESCC is beneficial to improve the diagnostic efficiency of preoperative CT.

Distribution of residual tumors in esophageal squamous cell carcinoma after neoadjuvant PD-1 blockade combined with chemotherapy.

The distribution of residual esophageal squamous cell carcinoma (ESCC) in the esophageal wall and resected lymph nodes was evaluated after neoadjuvant chemoimmunotherapy (nICT). Clinical data were collected from 137 ESCC patients who underwent anti-programmed death 1 therapy and esophagectomy. Ninety (65.7%) achieved an major pathological response (MPR) in the esophageal wall, and 27 (19.7%) achieved an MPR in the lymph nodes. Pathologically complete response (pCR, ypT0N0) was observed in 26 patients (19%). Residual tumors located in the mucosa and/or submucosa were found in 94.6% of nonpCR patients. In the minor responders, 97.8% had residual tumor >10% in the mucosa or submucosa. A preferential regression direction toward the lumen was found in 76.4% of prepT2 nonpCR patients, or 60.7% of prepT3-4a nonpCR patients. The correlation between pCR in the esophageal wall and in lymph nodes was not significant (P=0.143). Among 19 patients with pCR in resected recurrent laryngeal nerve (RLN) lymph nodes, 31.6% had residual tumor cells in other resected lymph nodes. A significant correlation was found between ypT/ypN downstaging and tumor regression grade (P<0.05). After nICT for ESCC, residual tumors were frequently found in the mucosa or submucosa, with relatively high responsiveness of the invasive front and a significant correlation with downstaging, which may help clinicians make appropriate decisions about postoperative treatment and surveillance. The differences in pCR status in primary tumors, resected lymph nodes, and RLN lymph nodes indicated the importance of assessing regression changes in all resected lymph nodes during clinical practice.

Initial experience with modified en bloc robot-assisted minimally invasive oesophagectomy for thoracic oesophageal squamous cell carcinoma.

The feasibility and safety of en bloc robot-assisted minimally invasive oesophagectomy (RAMIE) need to be verified. Forty-seven patients who received conventional RAMIE and 31 who received modified en bloc RAMIE at Henan Cancer Hospital were included in the study cohort. We compared the perioperative outcomes of conventional RAMIE and modified en bloc RAMIE. Compared with the conventional RAMIE group, the en bloc RAMIE group yielded a higher total number of lymph nodes (p=0.001), especially thoracic lymph nodes (p=0.025) and left recurrent laryngeal nerve (RLN) lymph nodes (p=0.005). No notable differences were found in the rate of total complications (p=0.663) or RLN injury (p=0.891) between the two groups. The preoperative and postoperative serological indicators were comparable between the two groups. Modified en bloc RAMIE was safe and feasible for patients with oesophageal squamous cell carcinoma and improved lymph node dissection, especially thoracic and left RLN lymph node dissection.

Impact of Robot-Assisted Minimally Invasive Esophagectomy for Esophageal Cancer: A Propensity Score-Matched Short-Term Analysis.

We compared short-term clinical outcomes between robotic-assisted minimally invasive esophagectomy (RAMIE) and video-assisted thoracic esophagectomy (VATS-E) using propensity score-matched analysis. We enrolled 114 patients with esophageal cancer who underwent esophagectomy at our institution from January 2013 to January 2022. Propensity score matching was performed to minimize selection bias between the RAMIE and VATS-E groups. After propensity score matching, 72 patients (RAMIE group, n = 36; VATS-E group, n = 36) were selected for analysis. No significant differences in clinical variables were observed between the two groups. The RAMIE group had a significantly longer thoracic operation time (313 ± 40 vs. 295 ± 35 min, P = 0.048), a higher number of right recurrent laryngeal nerve lymph nodes (4.2 ± 2.7 vs. 2.9 ± 1.9, P = 0.039), and a shorter postoperative hospital stay (23.2 ± 12.8 vs. 30.4 ± 18.6 days, P = 0.018) than the VATS-E group. The RAMIE group tended to have a lower rate of anastomotic leakage (13.9% vs. 30.6%) than the VATS-E group, although the difference was not statistically significant (P = 0.089). No significant differences were found in recurrent laryngeal nerve paralysis (11.1% vs. 13.9%, P = 0.722) or pneumonia (13.9% vs. 13.9%, P = 1.000) between the RAMIE group and the VATS-E group. Although RAMIE for esophageal cancer requires a longer thoracic surgery time, it might be a feasible and safe alternative to VATS-E for treating esophageal cancer. Further analysis is needed to clarify the advantages of RAMIE over VATS-E, especially in terms of long-term surgical outcomes.

Left versus right approach for middle and lower esophageal squamous cell carcinoma: A propensity score-matched study.

Despite superior short-term outcomes, there is considerable debate about the oncological efficacy of the left approach esophagectomy for middle and lower squamous esophageal carcinoma (ESCC). A propensity score-matched retrospective study was conducted to evaluate the left approach's short- and long-term effects. We recorded data from patients with ESCC who underwent curative resection via the left or right approach between January 2010 and December 2015. Propensity score matching (PSM) was performed, and maximally selected rank statistics (MSRS) were utilized to determine the appropriate number of lymph nodes to resect during esophagectomy. One hundred and forty-eight ESCC patients underwent esophagectomy via the right approach, and 108 underwent the left approach esophagectomy. After PSM, the left approach esophagectomy showed statistically significant superiority in operative time and time to oral intake, and there was a trend toward a shorter length of hospital stay. Fewer cervical, upper thoracic, and recurrent laryngeal nerve lymph nodes were harvested via the left approach than the right approach; the total number of lymph nodes harvested via the left and right approaches was similar. Similar long-term survival outcomes were achieved. MSRS suggested that at least 25 lymph nodes are needed to be resected during esophagectomy to improve survival in N0 patients. The left approach esophagectomy might facilitate postoperative recovery in patients with middle and lower ESCC. With adequate lymphadenectomy, the left approach esophagectomy might achieve similar long-term outcomes for middle and lower ESCC patients.

The development of a nomogram model for predicting left recurrent laryngeal nerve lymph node metastasis in esophageal cancer based on radiomics and clinical factors

The lymph node dissection for esophageal cancer is controversial. Some prediction models of lymph node metastasis (LNM) use the short diameter of lymph nodes measured by computed tomography (CT) examination as a predictor, but the size of that for judging metastasis is still controversial. However, radiomics can extract some features in tumors that cannot be obtained by naked eyes, which may have a higher value in predicting LNM. In this study, a nomogram was developed based on radiomics and clinical factors to predict left recurrent laryngeal nerve lymph node (RLNN) metastasis in patients with esophageal squamous cell carcinoma (ESCC). There were 350 patients included in this retrospective study. And the postoperative pathological results determined whether there was left RLNN metastasis. A univariate analysis was conducted of the clinical data. The least absolute shrinkage and selection operator regression analysis was conducted to filter the radiomics features extracted from CT images. The multivariate logistic regression equation was used to construct a nomogram. The area under the curve (AUC) was used to evaluate the predictive ability. Due to the small sample size, we chose to perform internal validation after the model was established by 10-fold cross-validation, Harrell's concordance index (C-index), bootstrap validation and calibration. Ultimately, 3 indicators were screened out; that is, tumor location, surface volume ratio, and run-length non-uniformity. We then constructed the nomogram using these 3 indicators. The model had good accuracy and calibration performance. It has an AUC of 0.903 (95% confidence interval: 0.861-0.945), a sensitivity of 0.873, and a specificity of 0.756. Ten-fold cross-validation showed that the sensitivity and specificity of the training set were 88.08% and 75.81%, and the validation set had a sensitivity of 85.08% and a specificity of 75.49%. The Brier score was 0.074, and C-index was 0.904, which indicated good consistency between the actual and predicted results. A nomogram constructed based on radiomics features and clinical factors can be used to predict the metastasis of left RLNN in patients with ESCC in a non-invasive way, which provided a reference for clinicians to formulate individualized lymph node dissection plans.

Perioperative Outcomes and Learning Curve of Robot-Assisted McKeown Esophagectomy

BackgroundThis study aimed to evaluate the perioperative outcomes of patients undergoing robot-assisted McKeown esophagectomy (RAME) and the learning curves of surgeons performing RAME at a single center. MethodsPerioperative outcomes of RAME and video-assisted McKeown esophagectomy (VAME) were compared after eliminating confounding factors by propensity score matching (PSM). The cumulative sum (CUSUM) method was used to evaluate the learning curves of RAME for a single surgical team. ResultsIn general, a total of 198 patients with esophageal cancer (RAME: 45 patients, VAME: 153 patients) were included in this study, and 43 pairs of patients receiving RAME or VAME were matched using 1:1 PSM analysis. Those in the RAME group had more lymph nodes dissected in the total lymph nodes (median 29.0 vs. 26.0, P = 0.011) and the upper mediastinum (median 8.0 vs. 6.0, P < 0.001), especially the left recurrent laryngeal nerve (RLN) lymph node (median 4.0 vs. 2.0, P = 0.001). According to the trend of the CUSUM plot, the learning curve was divided into two stages at the 20th RAME procedure. After mastering the learning curve, RAME harvested a significantly higher number of upper mediastinal lymph nodes (median 9.0 vs. 6.0, P = 0.001), left RLN lymph nodes (median 5.0 vs. 3.5, P = 0.003), and right RLN lymph nodes (median 4.0 vs. 2.0, P = 0.002). Meanwhile, the incidence of postoperative pneumonia in the proficiency phase was significantly lower than that in the learning phase (4.0% vs. 25.0%, P = 0.04). ConclusionsRAME improved left RLN lymph node dissection. Surgeons with extensive VAME experience need at least 20 cases to achieve early proficiency in RAME.

166. A STUDY OF THE LEARNING CURVE FOR LAPAROSCOPIC-ASSISTED SINGLE-PORT MEDIASTINOSCOPIC ESOPHAGECTOMY

Abstract Laparoscopic-assisted single-port mediastinoscopic esophagectomy is a safe and effective emerging minimally invasive esophagectomy. However, nothing has been reported about the learning curve for this technique. The goal of this study was to analyze the learning curve of this technique and to determine the number of procedures performed to achieve different levels of proficiency to improve surgeons’ understanding of the learning process of this new technique. This study retrospectively collected clinical data on consecutive laparoscopic-assisted single-port mediastinoscopic esophagectomies performed by the same surgeon at our center from October 2016 to August 2021. A simple scatter plot of the number of procedures versus procedure time and its trend line were plotted, using procedure time as an indicator of efficiency. Learning curves were quantitatively assessed by unadjusted cumulative sum values using the cumulative summation method, different segments were derived using joint point linear regression analysis, and variables were compared between subgroups using trend analysis. The survival analysis was performed using the Kaplan–Meier method. The learning curve could be divided into 3 different stages: the 1st–91st, 91st-125th, and 125th-182nd procedures comprised the preliminary, transition, and proficient stages, respectively. Compared with the preliminary stage, the procedure time, bleeding volume, postoperative hospital stays, and the incidence of anastomotic fistula were significantly lower in the proficiency stage, whereas the number of harvested lymph nodes and the rate of recurrent laryngeal nerve lymph node harvest was significantly higher. Additionally, there were no significant differences in overall survival and disease-free survival at different stages for patients with all, different T stages, and different N stages within 1 year postoperatively. In this study, there may be 3 stages of varying proficiency in the learning curve of laparoscopic-assisted single-port mediastinoscopic esophagectomy. Approximately 91 consecutive procedures were required to overcome the preliminary stage, whereas proficiency in this technique required approximately 125 consecutive procedures. Moreover, as the learning curve reached the proficiency stage, the perioperative indicators tended to stabilize. Furthermore, the short-term survival of patients might not be influenced by technical proficiency.

196. RISK FACTORS OF CERVICAL LYMPH NODE METASTASIS IN ESCC AND ESTABILISHMENT OF PREDICTION MODEL

Abstract Cervical lymph node metastasis of esophageal squamous cell carcinoma (ESCC) is an important basis for lymph node dissection of ESCC. Now, there are still disputes about whether to perform two field lymph node dissection or three field lymph node dissection. Establishing prediction model by analysis big data could promote the accuracy of prediction of cervical lymph node metastasis in patients with ESCC which can help clinicians to select individualized surgical scheme for patients. The clinical data of 102 consecutive patients with ESCC who underwent radical esophagectomy and three-field lymph node dissection between December 2015 to December 2021 were retrospectively analyzed. They were divided into positive group and negative group according to cervical lymph node metastasis. The differences between the two groups were compared, and after the univariate analysis those who were statistically significant were included in multivariable logistic regression analysis to establish the risk prediction model and plot a nomogram by software R. Among the 102 patients, univariate analysis(P&amp;lt;0.2)indicated that cervical lymph node metastasis of ESCC was related to the distance from upper edge of the tumor to the incisors (P = 0.101), vascular invasion (P = 0.144) and recurrent laryngeal nerve lymph nodes metastasis (P = 0.159). Multivariate logistic regression analysis showed that the distance from upper edge of the tumor to the incisors (P = 0.032) and the vascular invasion (P = 0.147) were independent risk factors. The AUC of ROC curve is 0.6817 (95% confidence interval: 0.5775–0.7859) and the Youden index is 0.294, 95% CI (0.620, 0.742). The prediction model includes two variables: the distance from upper edge of the tumor to the incisors and the vascular invasion. It plays a certain role in predicting the risk of cervical lymph node metastasis of ESCC, and can assist doctors in individualized treatment for patients with ESCC.

513. RISK FACTORS OF CERVICAL LYMPH NODE METASTASIS IN ESOPHAGEAL SQUAMOUS CELL CARCINOMA AND ESTABLISHMENT OF RISK PREDICTION MODEL

Abstract Cervical lymph node metastasis of esophageal squamous cell carcinoma (ESCC) is an important basis for lymph node dissection of ESCC. Now, there are still disputes about whether to perform two field lymph node dissection or three field lymph node dissection. Establishing prediction model by analysis big data could promote the accuracy of prediction of cervical lymph node metastasis in patients with ESCC which can help clinicians to select individualized surgical scheme for patients The clinical data of 102 consecutive patients with ESCC who underwent radical esophagectomy and three-field lymph node dissection between September 2015 to December 2021 were retrospectively analyzed. They were divided into positive group and negative group according to cervical lymph node metastasis. The differences between the two groups were compared, and after the univariate analysis those who were statistically significant were included in multivariable logistic regression analysis to establish the risk prediction model and plot a nomogram by software R. Among the 102 patients, univariate analysis (P&amp;lt;0.2) indicated that cervical lymph node metastasis of ESCC was related to the distance from upper edge of the tumor to the incisors (P=0.085), vascular invasion (P= 0.141) and recurrent laryngeal nerve lymph nodes metastasis (P = 0.157). Multivariate logistic regression analysis showed that the distance from upper edge of the tumor to the incisors (P=0.153) and the vascular invasion (P=0.198) were independent risk factors. The AUC of ROC curve is 0.682 (95% confidence interval: 0.578-0.786) and the Youden index is 0.294, 95% CI (0.620, 0.742). The prediction model includes two variables: the distance from upper edge of the tumor to the incisors and the vascular invasion. It plays a certain role in predicting the risk of cervical lymph node metastasis of ESCC, and can assist doctors in individualized treatment for patients with ESCC.

182. LAPAROSCOPIC-ASSISTED SINGLE-PORT MEDIASTINOSCOPIC ESOPHAGECTOMY CAN PROVIDE A SAFE AND EFFECTIVE SURGICAL OPTION FOR PATIENTS WITH SPECIFIC ESOPHAGEAL CANCERS

Abstract The majority of traditional minimally invasive esophagectomies are transthoracic esophagectomies. However, transthoracic esophagectomy is often difficult to perform in some patients with pulmonary insufficiency, severe pleural adhesions, chest deformities, and poor tolerance for single-lung ventilation. For this reason, we propose laparoscopic-assisted single-port mediastinoscopic esophagectomy as a potential surgical treatment for patients who are unsuitable for transthoracic esophagectomy. The goal of this study was to report the effectiveness and safety of its treatment. This study retrospectively collected clinical data from hard-to-reach transthoracic patients who underwent laparoscopic-assisted single-port mediastinoscopic esophagectomy at our center from October 2016 to August 2021 to report their perioperative treatment outcomes. Data for continuous variables are expressed as mean ± standard deviation, and categorical variables are expressed as n [%]. All data were analyzed using SPSS 25.0 software. A total of 8 cases were included and all completed the surgery successfully. The average operating time was 266.14 min, the average intraoperative bleeding was 114.29 mL, the average number of lymph nodes obtained was 13.29, the average number of recurrent laryngeal nerve (RLN) lymph nodes was 3.14, the rate of RLN lymph nodes obtained was 75%, the average postoperative hospital stay was 22.29 days. Postoperative complications included type I vocal cord paralysis [37.5%], anastomotic leak [25%], pneumonia [12.5%], pleural effusion [25%], and type I Chyle Leak [12.5%], with no perioperative deaths. There was one recurrence and no death within 1 year postoperatively. The results of this study suggest that laparoscopic-assisted single-port mediastinoscopic esophagectomy can provide a safe and effective treatment option for patients with esophageal cancer who have difficulty undergoing transthoracic esophagectomy and can achieve a more satisfactory short-term survival outcome.

Analysis of the Clinical Effect of Recurrent Laryngeal Nerve Lymph Node Dissection by Minimally Invasive McKeown Esophagealectomy

Analysis of the Clinical Effect of Recurrent Laryngeal Nerve Lymph Node Dissection by Minimally Invasive McKeown Esophagealectomy

A novel web-based dynamic nomogram for recurrent laryngeal nerve lymph node metastasis in esophageal squamous cell carcinoma.

BackgroundPatients with esophageal squamous cell carcinoma (ESCC) are liable to develop recurrent laryngeal nerve (RLN) lymph node metastasis (LNM). We aimed to assess the predictive value of the long diameter (LD) and short diameter (SD) of RLN lymph node (LN) and construct a web-based dynamic nomogram for RLN LNM prediction.MethodsWe reviewed 186 ESCC patients who underwent RLN LN dissection from January 2016 to December 2018 in the Affiliated Hospital of North Sichuan Medical College. Risk factors for left and right RLN LNM were determined by univariate and multivariate analyses. A web-based dynamic nomogram was constructed by using logistic regression. The performance was assessed by the area under the curve (AUC) and Brier score. Models were internally validated by performing five-fold cross-validation.ResultsPatients who underwent left and right RLN LN dissection were categorized as left cohort (n = 132) and right cohort (n = 159), with RLN LNM rates of 15.9% (21/132) and 21.4% (34/159), respectively. The AUCs of the LD (SD) of RLN LN were 0.663 (0.688) in the left cohort and 0.696 (0.705) in the right cohort. The multivariate analysis showed that age, the SD of RLN LN, and clinical T stage were significant risk factors for left RLN LNM (all P < 0.05), while tumor location, the SD of RLN LN, and clinical T stage were significant risk factors for right RLN LNM (all P < 0.05). The dynamic nomograms showed reliable performance after five-fold cross-validation [(left (right), mean AUC: 0.814, range: 0.614–0.891 (0.775, range: 0.084–0.126); mean Brier score: 0.103, range: 0.084–0.126 (0.145, range: 0.105–0.206)], available at https://mpthtw.shinyapps.io/leftnomo/ and https://mpthtw.shinyapps.io/rightnomo/.ConclusionThe LD and SD of RLN LN are inadequate to predict RLN LNM accurately, but online dynamic nomograms by combined risk factors show better prediction performance and convenient clinical application.

Clinical Outcome of Intraoperative Recurrent Laryngeal Nerve Monitoring during Thoracoscopic Esophagectomy and Mediastinal Lymph Node Dissection for Esophageal Cancer.

Mediastinal lymph dissection in esophagectomy for patients with esophageal cancer is important. The dissection of recurrent laryngeal nerve (RLN) lymph nodes could cause RLN injury, vocal cord palsy, pneumonia, and respiratory failure. This retrospective study aimed to evaluate the effects of intraoperative RLN monitoring in esophagectomy and mediastinal lymph node dissection in preventing RLN injury and vocal cord palsy. This study included 75 patients who underwent minimally invasive esophagectomy and mediastinal lymph node dissection for esophageal cancer with (38 patients) and without (37 patients) IONM at Changhua Christian Hospital from 2015 to 2020. The surgical and clinical outcomes were reviewed. Patients in the IONM group had more advanced clinical T status, shorter operation time (570 vs. 633 min, p = 0.007), and less blood loss (100 mL vs. 150 mL, p = 0.019). The IONM group had significantly less postoperative vocal palsy (10.5% vs. 37.8%, p = 0.006) and pneumonia (13.2% vs. 37.8%, p = 0.014) than that in the non-IONM group. IONM was an independent factor for less postoperative vocal cord palsy that was related to postoperative 2-year survival. This study demonstrated that IONM could reduce the incidence of postoperative vocal cord palsy and pneumonia.