Recurrent Laryngeal Nerve Lymph Node Research Articles

Dissection of the lymph nodes along the recurrent laryngeal nerve in robotic esophagectomy

Lymph node (LN) metastasis serves as a pivotal prognostic determinant in esophageal cancer, particularly in cases of squamous cell carcinoma (SqCC). The involvement of LN metastasis frequently extends to the LNs along the recurrent laryngeal nerve (RLN). Radical dissection of these nodes is imperative for precise staging and the prevention of loco-regional recurrence. Historically, the emphasis on RLN node dissection has been evident in numerous literature, establishing it as a mandatory procedure in different countries. Nevertheless, the risk of RLN palsy following such dissection is a substantial concern, given its association with significant postoperative complications and long-term implications for quality of life. Recent literature has highlighted RLN node dissection in robotic surgery, demonstrating favorable outcomes in comparison to alternative surgical modalities. This review paper aims to comprehensively assess prior publications on this subject, elucidating the outcomes and implications of RLN node dissection in robotic esophagectomy (RE).

Recurrent laryngeal nerve lymph node dissection with subcomplete sealing using advanced bipolar energy device in minimally invasive esophagectomy.

Recurrent laryngeal nerve (RLN) palsy is a complication that must be avoided during esophagectomy. While RLN injury is thought to be caused by thermal spread from electric devices, electric devices are useful to avoid bleeding. When dissecting lymph nodes around RLNs, to seal small vessels, we use subcomplete technique with advanced bipolar. We describe our surgical technique, termed the subcomplete sealing technique, in RLN lymph node dissection. The first step is to perform blunt dissection with forceps on both sides of the esophageal branch near the right RLN. A distance of at least 2 mm from the RLN was preferred. Sealing with advanced bipolar often causes tissue shrinkage, pulling the RLN near the device. To prevent this, sealing should be stopped before reaching completion. Although the sealing was not complete, it was sufficient to seal the small vessels. After subcomplete sealing, the sealed tissues were dissected using laparoscopic scissors. The lymph nodes around left RLN are dissected in the same manner. A total of 76 patients received esophagectomy with the subcomplete technique. Grade IIIa RLN palsy occurred in three cases (3.95%). Over Grade IIIb RLN palsies did not occur. This subcomplete sealing technique can assist surgeons in performing RLN lymph node dissection without bleeding and increasing the rate of RLN palsy.

Managing esophageal squamous cell carcinoma after cervical radiotherapy for a head and neck cancer: esophagectomy remains a viable option.

Managing esophageal squamous cell carcinoma (ESCC) in patients with a history of cervical radiotherapy for a head and neck cancer (HNC) often requires a careful evaluation of esophagectomy due to concerns regarding complications and prognosis. This study evaluates the periesophagectomy and oncological outcomes of such patients. Patients diagnosed with ESCC between January 2010 and August 2023 and who had undergone esophagectomy with cervical anastomosis were retrospectively reviewed. Patients were categorized into two groups based on the presence (group 1) or absence (group 2) of a history of radiotherapy for as HNC. After 1: 2 propensity score matching, the perioperative and oncological outcomes, including overall survival (OS) and recurrence-free survival (RFS), were evaluated. A total of 481 patients, 32 in group 1 and 449 in group 2, were included. After matching, group 1 patients and 64 patients in the group 2 were analyzed. All the patients in group 1 were males, and their mean age was 56years. The median radiation dose was 69Gy. The rates of anastomosis leakage, pneumonia, respiratory failure, and reoperation were comparable between the two groups. However, vocal cord palsy occurred more frequently in group 1, particularly in those with recurrent laryngeal nerve lymph node dissection (37.5%). The 3-year OS (69.6% vs. 75.2%; p = 0.26) and RFS (50.8% vs. 55.9%; p = 0.63) were similar between groups 1 and 2. In conclusion, perioperative and oncological outcomes were comparable between ESCC patients with and without prior HNC radiotherapy, supporting esophagectomy as a feasible option.

Comparison of three-dimensional vs. two-dimensional assisted thoracoscopy for recurrent laryngeal nerve lymph nodes dissection in esophagectomy: a retrospective study

BackgroundThis study aimed to explore the clinical value of 3D video-assisted thoracoscopic surgery in dissecting recurrent laryngeal nerve lymph nodes in patients undergoing minimally invasive esophagectomy.MethodsA retrospective cohort study was conducted on 205 patients, including 120 males, who underwent esophagectomy from May 2018 to May 2020 in the Department of Thoracic Surgery at the Affiliated Huai’an No.1 People’s Hospital of Nanjing Medical University. Perioperative parameters, including intraoperative blood loss, operation time, the number of dissected recurrent laryngeal nerve lymph nodes, the incidence and degree of postoperative recurrent laryngeal nerve injury, the volume of postoperative thoracic drainage, and postoperative complications, were compared between the 3D and 2D groups.ResultsThere were no significant differences in the preoperative baseline data between these two groups (P > 0.05). The number of dissected recurrent laryngeal nerve lymph nodes in the 3D group was significantly higher than in the 2D group (P < 0.05). The operation times were significantly shorter in the 3D group than in the 2D group (P < 0.05). The volume of thoracic drainage in the first 2 days was significantly less in the 3D group than in the 2D group (P < 0.05).ConclusionsCompared to the 2D system, the application of 3D video-assisted thoracoscopic surgery in minimally invasive esophagectomy can increase the number of dissected recurrent laryngeal nerve lymph nodes and ensure safety. Additionally, it can reduce the duration of the operation, decrease early postoperative thoracic drainage volume, and promote patient recovery.

Usefulness of an Artificial Intelligence Model in Recognizing Recurrent Laryngeal Nerves During Robot-Assisted Minimally Invasive Esophagectomy.

Recurrent laryngeal nerve (RLN) palsy is a common complication in esophagectomy and its main risk factor is reportedly intraoperative procedure associated with surgeons' experience. We aimed to improve surgeons' recognition of the RLN during robot-assisted minimally invasive esophagectomy (RAMIE) by developing an artificial intelligence (AI) model. We used 120 RAMIE videos from four institutions to develop an AI model and eight other surgical videos from another institution for AI model evaluation. AI performance was measured using the Intersection over Union (IoU). Furthermore, to verify the AI's clinical validity, we conducted the two experiments on the early identification of RLN and recognition of its location by eight trainee surgeons with or without AI. The IoUs for AI recognition of the right and left RLNs were 0.40 ± 0.26 and 0.34 ± 0.27, respectively. The recognition of the right RLN presence in the beginning of right RLN lymph node dissection (LND) by surgeons with AI (81.3%) was significantly more accurate (p = 0.004) than that by surgeons without AI (46.9%). The IoU of right RLN during right RLN LND recognized by surgeons with AI (0.59 ± 0.18) was significantly higher (p = 0.010) than that by surgeons without AI (0.40 ± 0.29). Surgeons' recognition of anatomical structures in RAMIE was improved by our AI system with high accuracy. Especially in right RLN LND, surgeons could recognize the RLN more quickly and accurately by using the AI model.

Thoracoscopic three-port single versus multiple intercostal for radical resection of esophageal cancer: a retrospective analysis

BackgroundThe purpose of this retrospective study was to compare the safety and feasibility of single-intercostal totally minimally invasive Ivor Lewis esophagectomy (MIIE) with those of multiple-intercostal MIIE.MethodsBetween January 2016 and December 2022, clinical data were collected for 528 patients who successfully underwent totally minimally invasive esophagectomy. Among these patients, 294 underwent MIIE, with 200 undergoing the single-intercostal approach and 94 undergoing the multiple-intercostal approach. Propensity score matching (PSM) was applied to the cohort of 294 patients. Subsequently, perioperative outcomes and other pertinent clinical data were analyzed retrospectively.ResultsA total of 294 patients were subjected to PSM, and 89 groups of patient data (178 persons in total) were well balanced and included in the follow-up statistics. Compared to the multiple intercostal group, the single intercostal group had a shorter operative time (280 min vs. 310 min; p < 0.05). Moreover, there was no significant difference in the incidence of major perioperative complications (p > 0.05). The total number of lymph nodes sampled (25.30 vs. 27.55, p > 0.05) and recurrent laryngeal nerve lymph nodes sampled on the both sides (p > 0.05) did not significantly differ. The single intercostal group had lower postoperative long-term usage of morphine (0,0–60 vs. 20,20–130; p < 0.01), total temporary addition (10,0–30 vs. 20,20–40; p < 0.01) and temporary usage in the first 3 days after surgery (0,0–15 vs. 10,10–20; p < 0.01) than did the multicostal group.There were no significant differences in age, sex, tumor location or extent of lymphadenectomy or in the clinical factors between the single-intercostal group (p > 0.05).ConclusionsBoth techniques can be used for the treatment of esophageal cancer. Compared to multiple intercostal MIIE, the feasibility of which has been proven internationally, the single intercostal technique can also be applied to patients of different age groups and sexes and with different tumor locations. It can provide surgeons with an additional surgical option.Trial registrationThis study was retrospectively registered by the Ethics Committee of the Second Affiliated Hospital of Zhejiang University School of Medicine, and written informed consent was exempted from ethical review. The registration number was 20,230,326. The date of registration was 2023.03.26.

246. EFFECT OF INTRAOPERATIVE NERVE MONITORING DURING MINIMALLY INVASIVE ESOPHAGECTOMY

Abstract Background Recurrent laryngeal nerve (RLN) lymphadenectomy is a crucial step during esophagectomy. However, it is technically demanding and associated with a significant risk of RLN injury. Despite several studies demonstrating the feasibility of intraoperative nerve monitoring (IONM) during esophageal surgery, routine utilization of IONM during minimally invasive esophagectomy has not become common, and there is limited evidence to provide robust guidance. Here, we describe our experience with IONM during minimally invasive McKeown esophagectomy. Methods Data from 115 consecutive patients who underwent bilateral RLN lymphadenectomy during thoracoscopic McKeown esophagectomy for esophageal squamous cell carcinoma (ESCC) by a single surgeon between July 2017 and November 2023 were reviewed. The cohort was divided into three groups: Group 1 (initial 23 cases without IONM), Group 2 (middle 46 cases without IONM), and Group 3 (late 46 cases with IONM). We compared the number of resected lymph nodes and the incidence of vocal cord palsy (VCP) among the three groups. Results The mean number of resected right-side RLN lymph nodes was 1.21, 2.30, and 3.28 in Groups 1, 2, and 3, respectively. A significant difference was noted between Groups 2 and 3 (p = 0.03, Kruskal-Wallis test). The mean number of resected left-side RLN lymph nodes was 1.13, 2.70, and 2.67 in Groups 1, 2, and 3, respectively. A significant difference was noted between Groups 1 and 2 (p = 0.009), but not between Groups 2 and 3. The incidence of VCP was 8.7%, 8.7%, and 10.9% in Groups 1, 2, and 3, respectively. Compared to Group 2, the utilization of IONM in Group 3 did not reduce the postoperative VCP rate (OR: 1.280, 95% CI: 0.321-5.107). Conclusions With increasing experience, the number of resected RLN lymph nodes significantly increased. However, the utilization of IONM did not further improve left-side RLN lymphadenectomy or reduce the VCP rate.

807. A REVISED APPROACH TO THE ESOPHAGOGASTRIC JUNCTION: A MODIFIED SIEWERT CLASSIFICATION

Abstract Background Esophagogastric junction (EGJ) adenocarcinomas are challenging due to their anatomical and histopathological features and treated either as part of the esophagus or stomach cancers. Siewert (S) and Nishi classifications rely on the tumor’s epicenter to guide treatment decisions, which can lead to diagnostic and therapeutic inconsistencies. Moreover, recent studies helped define the optimal extent of lymphadenectomy for EGJ cancers. Here we present our standardized approach to EGJ cancers that integrates these insights, providing a framework to guide clinical decision-making. Methods Our modified classification relies on tumor extent rather than the epicentre, based on endoscopic measurement of the proximal and the distal limits, and the exact location of the EGJ. This approach classifies tumors based on their extent which results into six categories: SI, SI/II, SII, SII/III, SIII, and SI/II/III. Lower esophageal tumors whose distal limit lies between + 1cm and -2cm are classified as I/II. Cardia tumors whose proximal limit falls between those boundaries are II/III. Tumors that span more cephalad than + 1cm and more distally than – 2cm, are I/II/III. For Siewert I, I/II and II tumors, surgical management depends on the extent of esophageal involvement, mainly dictated by the probability of mediastinal basement nodal involvement, as defined by Kurokawa et al (2019). Additionally, a 3-field lymphadenectomy is performed when there is involvement of the cervical or recurrent laryngeal nerve lymph node stations. Results In SI, SI/II, and SI/II/III, with esophageal involvement exceeding 4 cm we favor a transthoracic esophagectomy (TTE) with total thoracic lymphadenectomy. If the involvement is between 1-4 cm, a transhiatal esophagectomy (THE) with lower mediastinal lymphadenectomy is performed. In SII, THE is done for 0-1 cm of involvement; absence of esophageal involvement permits a transhiatal extended total gastrectomy (eTG) with abdominal D2 lymphadenectomy and intra-operative margin status assessment via frozen sections. In SI/II/III and esophageal involvement of more than 4 cm, TTE is required; for esophageal involvement of 1-4 cm, we perform a THE and total gastrectomy with abdominal D2 lymphadenectomy based on distal margin findings. Conclusion This proposed modification to the classification of EGJ adenocarcinomas introduces a comprehensive framework that is tailored to the extent of tumor involvement. By addressing the limitations of existing systems and incorporating current insights, this updated classification aims to improve patient categorization and standardize treatment protocols, potentially leading to enhanced clinical outcomes.

552. COMPARING ROBOTIC ESOPHAGECTOMY TO VIDEO-ASSISTED THORACOSCOPIC ESOPHAGECTOMY FOR ESOPHAGEAL SQUAMOUS CELL CARCINOMA: RESULTS FROM THE REVATE RANDOMIZED CLINICAL TRIAL

Abstract Background The treatment of esophageal squamous cell carcinoma (ESCC) includes dissecting lymph nodes along the recurrent laryngeal nerve (RLN), which is oncologically important but is technical demanding. Vocal cord palsy as a result from RLN injury, carries significant morbidities. This randomized clinical trial (RCT) compared the efficacy and safety of robotic esophagectomy (RE) and video-assisted thoracoscopic esophagectomy (VATE) for performing RLN lymph node dissection (LND) Methods We conducted a multicenter RCT(NCT03713749) from November 2018 to March 2022, enrolling patients with ESCC who required McKeown esophagectomy. The primary endpoint was to determine the success rate of left RLN LND. Success was defined as the removal of lymph nodes confirmed by pathology, without causing permanent nerve palsy (duration &amp;gt; 6 months). Secondary endpoints encompassed perioperative and oncological outcomes. Results The per-protocol analysis included data from 203 patients (RE group: n=103; VATE group: n=100). The primary endpoint was achieved in 88.3% of the RE group and 69% of the VATE group (p&amp;lt;0.001). Additionally, the RE group had a higher mediastinal lymph node harvest (16 [12−22] versus 14 [10−20], p=0.04), shorter thoracic operating time (110 [89−137] min versus 124[103.5−154] min, p=0.004), and earlier drainage removal (4 [3−7] days versus 6 [4−9] days, p=0.007) compared to the VATE group. The two study arms exhibited comparable complication rates with no recorded in-hospital deaths in either group. Conclusion This multicenter trial demonstrates the effectiveness of RE in enhancing the feasibility and safety of RLN LND in ESCC. Additionally, RE leads to an improved mediastinal lymphadenectomy, shorter operating times, and earlier removal of drainage.

Metastatic patterns of subcarinal, right and left recurrent laryngeal nerve lymph nodes in thoracic esophageal squamous cell carcinoma without neoadjuvant therapy

PurposeThis research aimed to clarify the metastatic patterns of subcarinal, right and left recurrent laryngeal nerve lymph nodes in thoracic esophageal squamous cell carcinoma and to investigate appropriate strategies for lymph node dissection.MethodsPatients with thoracic esophageal squamous cell carcinoma receiving esophagectomy from December 2020 to April 2024 were retrospectively analyzed. Risk factors for subcarinal, right and left recurrent laryngeal nerve lymph nodes metastasis were determined by chi-square test and multivariate logistic regression analysis. We visualized the metastasis rates of these specific lymph nodes based on the different clinicopathological characteristics. Correlation between subcarinal, right and left recurrent laryngeal lymph nodes metastasis and postoperative complications were also analyzed.ResultsA total of 503 thoracic esophageal squamous carcinoma patients who underwent esophagectomy were enrolled. The metastasis rates of subcarinal, right and left recurrent laryngeal nerve lymph nodes were 10.3%, 10.3%, and 10.9%, respectively. The lymphovascular invasion status and tumor location were the significant predictors for subcarinal and right recurrent laryngeal nerve lymph nodes metastasis, respectively (P < 0.001 and P = 0.013). For left recurrent laryngeal nerve lymph node metastasis, younger age (P = 0.020) and presence of lymphovascular invasion (P = 0.009) were significant risk factors. Additionally, pulmonary infection is the most frequent postoperative complication in patients with dissection of subcarinal, right and left recurrent laryngeal lymph nodes. There was no significant difference in the incidence of anastomotic leakage (P = 0.872), pulmonary infection (P = 0.139), chylothorax (P = 0.702), and hoarseness (P = 0.179) between the subcarinal lymph node dissection cohort and the reservation cohort. The incidence of hoarseness significantly increased in both right (P = 0.042) and left (P = 0.010) recurrent laryngeal nerve lymph nodes dissection cohorts compared by the reservation cohorts, with incidence rates of 5.9% and 6.7%, respectively.ConclusionsThe metastasis rates of subcarinal, right and left recurrent laryngeal nerve lymph nodes in thoracic esophageal squamous cell carcinoma were all over 10%. The dissection of subcarinal lymph nodes does not increase postoperative complications risk, while recurrent laryngeal nerve lymph nodes dissection significantly increases the incidence of hoarseness. Thus, lymph node dissection of subcarinal lymph nodes should be conducted routinely, while recurrent laryngeal nerve lymph nodes dissection may be selectively performed in specific patients.

Multicentre randomized clinical trial on robot-assisted versus video-assisted thoracoscopic oesophagectomy (REVATE trial).

Surgery for oesophageal squamous cell carcinoma involves dissecting lymph nodes along the recurrent laryngeal nerve. This is technically challenging and injury to the recurrent laryngeal nerve may lead to vocal cord palsy, which increases the risk of pulmonary complications. The aim of this study was to compare the efficacy and safety of robot-assisted oesophagectomy (RAO) versus video-assisted thoracoscopic oesophagectomy (VAO) for dissection of lymph nodes along the left RLN. Patients with oesophageal squamous cell carcinoma who were scheduled for minimally invasive McKeown oesophagectomy were allocated randomly to RAO or VAO, stratified by centre. The primary endpoint was the success rate of left recurrent laryngeal nerve lymph node dissection. Success was defined as the removal of at least one lymph node without causing nerve damage lasting longer than 6 months. Secondary endpoints were perioperative and oncological outcomes. From June 2018 to March 2022, 212 patients from 3 centres in Asia were randomized, and 203 were included in the analysis (RAO group 103; VAO group 100). Successful left recurrent laryngeal nerve lymph node dissection was achieved in 88.3% of the RAO group and 69% of the VAO group (P < 0.001). The rate of removal of at least one lymph node according to pathology was 94.2% for the RAO and 86% for the VAO group (P = 0.051). At 1 week after surgery, the RAO group had a lower incidence of left recurrent laryngeal nerve palsy than the VAO group (20.4 versus 34%; P = 0.029); permanent recurrent laryngeal nerve palsy rates at 6 months were 5.8 and 20% respectively (P = 0.003). More mediastinal lymph nodes were dissected in the RAO group (median 16 (i.q.r. 12-22) versus 14 (10-20); P = 0.035). Postoperative complication rates were comparable between the two groups and there were no in-hospital deaths. In patients with oesophageal squamous cell carcinoma, RAO leads to more successful left recurrent laryngeal nerve lymph node dissection than VAO, including a lower rate of short- and long-term recurrent laryngeal nerve injury. Registration number: NCT03713749 (http://www.clinicaltrials.gov).

Robot-assisted minimally invasive oesophagectomy versus thoracoscopic approach: multi-institutional study on short-term outcomes.

Robot-assisted minimally invasive oesophagectomy and conventional minimally invasive oesophagectomy are superior to open techniques. However, few studies have directly compared the outcomes of the two minimally invasive approaches. A retrospective study of patients from six medical centres with oesophageal squamous cell carcinoma who underwent minimally invasive oesophagectomy between 2015 and 2022. Perioperative outcomes were compared after applying inverse probability of treatment weighting. The study included 577 patients (robot-assisted minimally invasive oesophagectomy: 206; conventional minimally invasive oesophagectomy: 371). After applying inverse probability of treatment weighting, robot-assisted minimally invasive oesophagectomy was found to yield a higher number of mediastinal nodes compared with conventional minimally invasive oesophagectomy (14.86 versus 12.66, P = 0.017). Robot-assisted minimally invasive oesophagectomy was notably effective in retrieving upper mediastinal left recurrent laryngeal nerve nodes, averaging 1.97 nodes versus 1.14 nodes harvested by conventional minimally invasive oesophagectomy (P < 0.001). This was coupled by a significant decrease in nerve palsy rates (13.9% versus 22.8%, P = 0.020). A significantly larger percentage of patients in the robot-assisted minimally invasive oesophagectomy group had an uncomplicated postoperative course (51.8% versus 34%, P < 0.001). Robot-assisted minimally invasive oesophagectomy also led to a reduction in pneumonia rates (8.6% versus 15.2%, P = 0.041) and was linked to a shorter length of stay (length of stay; 16.64 versus 21.14 days, P = 0.007). The advantage of robot-assisted minimally invasive oesophagectomy in reducing the length of stay was especially pronounced in patients with a high Charlson co-morbidity index (≥2, mean difference 8.46 days; P = 0.0069) and those who underwent neoadjuvant therapy (mean difference 5.63 days; P < 0.001). In oesophageal squamous cell carcinoma, the use of robot-assisted minimally invasive oesophagectomy led to fewer cases of pneumonia and faster recovery compared with conventional minimally invasive oesophagectomy. Additionally, robot-assisted minimally invasive oesophagectomy significantly improved the feasibility and safety of performing lymph node dissection along the recurrent laryngeal nerve.

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.

Postoperative Radiotherapy in Curatively Resected Esophageal Squamous Cell Carcinoma With Occult Recurrent Laryngeal Nerve Lymph Node Metastasis.

Surgery is the mainstream treatment for early-stage esophageal squamous cell carcinoma (ESCC) and occult recurrent laryngeal nerve lymph node metastasis (RLNM) is not uncommon among those with R0 resection. The clinical value of postoperative radiotherapy (PORT) in patients with RLNM only is still controversial. Consecutive patients with early-stage ESCC treated with R0 resection and pathologically confirmed RLNM only from June 2012 to July 2022 were retrospectively reviewed. PORT, covering the supraclavicular and superior mediastinum area (small T-field) at a dose of 50.4Gy for 28 fractions, was performed in some patients. Propensity score matching (PSM) was performed to balance the baseline characteristics between patients with or without PORT. Pattern of failure, disease-free survival (DFS), and overall survival (OS) were compared. Among the 189 patients identified, 69 (35.5%) received PORT and the other 120 (63.5%) did not. After PSM, 154 patients were included in the matched cohort, including 62 in the PORT group and 92 in the non-PORT group. With a median follow-up of 48 (95% CI: 40.3-55.7) months, 69 patients developed their initial disease recurrence in the whole population and PORT significantly decreased the frequency of local recurrence (61.2% vs 21.4%) among those with recurrent disease. Additionally, in the PSM matched cohort, PORT significantly prolonged patients' DFS (HR 0.393, P = 0.002) and OS (HR 0.462, P = 0.020). Moreover, PORT remained as the independent factor associated with improved DFS (HR 0.360, P = 0.001) and OS (HR 0.451, P = 0.021) after multivariate Cox analyses. In addition, tumor location and pathological TNM stage were found to be independent prognostic factors associated with survival outcomes. PORT is associated with improved DFS and OS in ESCC patients with R0 resection and RLNM only, which warrants future validation.

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.