Postoperative recurrent laryngeal nerve palsy is associated with pneumonia in minimally invasive esophagectomy for esophageal cancer

Assessment of pre-extubating recurrent laryngeal nerve palsy using ultrasound in postoperative patients with esophageal cancer: a prospective observational study

PURPOSE

Ultrasound performed after extubation has been suggested to be useful for the diagnosis of recurrent laryngeal nerve (RLN) paralysis. However, the use of ultrasound for this purpose before extubation has not been examined. The aim of this study was to examine the versatility (interrater reliability) and usefulness of ultrasound for evaluating the movement of vocal cords before extubation.

METHODS

The subjects were 30 patients who underwent radical surgery for esophageal cancer from August 2020 to December 2021. An experienced examiner performed an ultrasound examination before and after elective extubation on the day after surgery to evaluate RLN paralysis and record videos. Bronchoscopy was then performed to make a definite diagnosis. Three anesthetists blinded to the diagnosis also evaluated the cases using the videos, and the versatility of the examination was determined using a kappa test.

RESULTS

The diagnostic accuracies of the examiner and three anesthetists were 76.7%, 50.0%, 53.3%, and 46.7%, respectively, and the kappa coefficients for the examiner with the anesthetists were 0.310, 0.502, and 0.169, respectively. The sensitivity, specificity, positive predictive value and negative predictive value for diagnosis of RLN paralysis by the examiner using ultrasound before extubation were 0.57, 0.95, 0.80, and 0.87, respectively.

CONCLUSION

These results indicate a lack of versatility of the ultrasound examination based on the low kappa coefficients. However, with an experienced examiner, ultrasound can serve as a non-invasive examination that can be performed before extubation with high accuracy and specificity for diagnosis of postoperative RLN paralysis.

Association of perioperative oral swallowing function with post-esophagectomy outcomes and nutritional statuses in patients with esophageal cancer

Dysphagia after esophagectomy is a serious complication; however, no method has been established to accurately assess swallowing function. We evaluated the association of swallowing function tests with patients' post-esophagectomy complications and nutritional statuses. We retrospectively reviewed the data of 95 patients with esophageal cancer who underwent esophagectomy between 2016 and 2021. We performed perioperative swallowing function tests, including the repetitive saliva swallowing test (RSST), maximum phonation time (MPT), and laryngeal elevation (LE). Patients with recurrent laryngeal nerve palsy (RLNP) and respiratory complications (RC) had significantly lower postoperative RSST scores than patients without them; the scores in patients with or without anastomotic leakage (AL) were similar. Postoperative MPT in patients with RLNP was shorter than that in patients without RLNP; however, it was similar to that in patients with or without AL and RC. LE was not associated with any complications. Patients with an RSST score ≤2 at 2 weeks post-esophagectomy had significant weight loss at 1, 6, and 12 months postoperatively compared with patients with an RSST score ≥3. The proportion of patients with severe weight loss (≥20% weight loss) within 1 year of esophagectomy was significantly greater in patients with RSST scores ≤2 than in those with RSST scores ≥3. Multivariate analysis showed that an RSST score ≤2 was the only predictor of severe post-esophagectomy weight loss. RSST scoring is a simple tool for evaluating post-esophagectomy swallowing function. A lower RSST score is associated with postoperative RLNP, RC, and poor nutritional status.

Prognostic Factors for Recovery from Left Recurrent Laryngeal Nerve Palsy After Minimally Invasive McKeown Esophagectomy: A Retrospective Study

BACKGROUND

Recurrent laryngeal nerve (RLN) palsy is a serious complication of esophagectomy that affects the patient's phonation and the ability to prevent life-threatening aspiration events. The aim of this single-center, retrospective study was to investigate the clinical course of left RLN palsy and to identify the main prognostic factors for recovery.

METHODS

The study cohort consisted of 85 patients who had developed left RLN palsy after minimally invasive McKeown esophagectomy. Vocal cord function was assessed in all participants through laryngoscopic examinations, both in the immediate postoperative period and during follow-up. Permanent palsy was defined as no evidence of recovery after 6 months. Univariate and multivariable logistic regression analyses were applied to evaluate the associations between different variables and the outcome of palsy.

RESULTS

Twenty-two (25.8%) patients successfully recovered from left RLN palsy. On multivariable logistic regression analysis, active smoking (odds ratio [OR] 0.335, p = 0.038) and the use of thoracoscopic surgery (vs. robotic surgery; OR 0.264, p = 0.028) were identified as independent unfavorable predictors for recovery from palsy. The estimated rates of recovery derived from a logistic regression model for patients harboring two, one, or no risk factors were 13.16%, 31.15-34.75%, and 61.39%, respectively.

CONCLUSION

Only one-quarter of patients who had developed left RLN palsy after minimally invasive McKeown esophagectomy were able to fully recover. Smoking habits and the surgical approach were identified as key determinants of recovery. Patients harboring adverse prognostic factors are potential candidates for early intervention strategies.

Perioperative Risk Factors for Postoperative Pulmonary Complications After Minimally Invasive Esophagectomy

Background

Postoperative pulmonary complications (PPCs) are the most prevalent complication after esophagectomy and are associated with a worse prognosis. This study aimed to investigate the perioperative risk factors for PPCs after minimally invasive esophagectomy (MIE).

Methods

Seven hundred and sixty-seven consecutive patients who underwent McKeown MIE via thoracoscopy and laparoscopy were retrospectively studied. Patient characteristics, perioperative data, and postoperative complications were analyzed.

Results

The incidence of PPCs after MIE was 25.2% (193/767). Univariate analysis identified age (odds ratio [OR] 1.022, P = 0.044), male sex (OR 2.955, P < 0.001), pulmonary comorbidities (OR 1.746, P = 0.032), chronic obstructive pulmonary disease (COPD) (OR 2.821, P = 0.003), former smoking status (OR 1.880, P = 0.001), postoperative albumin concentration (OR 0.941, P = 0.007), postoperative creatinine concentration (OR 1.011, P = 0.019), and perioperative transfusion (OR 2.250, P = 0.001) as risk factors for PPCs. In multivariate analysis, the independent risk factors for PPCs were male sex (OR 3.135, P < 0.001), body mass index (BMI) (OR 1.088, P = 0.002), COPD (OR 2.480, P = 0.012), neoadjuvant chemoradiotherapy (OR 2.057, P = 0.035), postoperative albumin concentration (OR 0.929, P = 0.002), and perioperative transfusion (OR 1.939, P = 0.013). The area under the receiver operating characteristic curve for the predictive model generated by multivariate logistic regression analysis was 0.671 (95% confidence interval 0.628-0.713).

Conclusions

Male sex, BMI, COPD, neoadjuvant chemoradiotherapy, postoperative albumin concentration, and perioperative transfusion were independent predictors of PPCs after MIE.

Impact of intraoperative fluid management on postoperative complications in patients undergoing minimally invasive esophagectomy for esophageal cancer: a retrospective single-center study

BACKGROUND

Esophagectomy is a high-risk procedure that can involve serious postoperative complications. There has been an increase in the number of minimally invasive esophagectomies (MIEs) being performed. However, the relationship between intraoperative management and postoperative complications in MIE remains unclear.

METHODS

After the institutional review board approval, we enrolled 300 patients who underwent MIE at Tohoku University Hospital between April 2016 and March 2021. The relationships among patient characteristics, intraoperative and perioperative factors, and postoperative complications were retrospectively analyzed. The primary outcome was the relationship between intraoperative fluid volume and anastomotic leakage, and the secondary outcomes included the associations between other perioperative factors and postoperative complications.

RESULTS

Among 300 patients, 28 were excluded because of missing data; accordingly, 272 patients were included in the final analysis. The median [interquartile range] operative duration was 599 [545-682] minutes; total intraoperative infusion volume was 3,747 [3,038-4,399] mL; total infusion volume per body weight per hour was 5.48 [4.42-6.73] mL/kg/h; and fluid balance was + 2,648 [2,015-3,263] mL. The postoperative complications included anastomotic leakage in 68 (25%) patients, recurrent nerve palsy in 91 (33%) patients, pneumonia in 62 (23%) patients, cardiac arrhythmia in 13 (5%) patients, acute kidney injury in 5 (2%) patients, and heart failure in 5 (2%) patients. The Cochrane-Armitage trend test indicated significantly increased anastomotic leakage among patients with a relatively high total infusion volume (P = 0.0085). Moreover, anastomotic leakage was associated with male sex but not with peak serum lactate levels. Patients with a longer anesthesia duration or recurrent nerve palsy had a significantly higher incidence of postoperative pneumonia than those without. Further, the incidence of postoperative pneumonia was not associated with the operative duration, total infusion volume, or fluid balance. The operative duration and blood loss were related to the total infusion volume. Acute kidney injury was not associated with the total infusion volume or serum lactate levels.

CONCLUSIONS

Among patients who underwent MIE, the total infusion volume was positively correlated with the incidence of anastomotic leakage. Further, postoperative pneumonia was associated with recurrent nerve palsy but not total infusion volume or fluid balance.

Comparison of two different methods for lymphadenectomy along the left recurrent laryngeal nerve by minimally invasive esophagectomy in patients with esophageal squamous cell carcinoma: a prospective randomized trial

BACKGROUND

Lymph nodes along the left recurrent laryngeal nerve (LRLN) is thought to be highly involved in esophageal cancer. Given the unique anatomical positioning of the nerve, performing lymphadenectomy in this region requires advanced techniques within limited working space. Meanwhile, high incidence of morbidity and mortality is associated with lymphadenectomy. Although several methods have been applied to reduce the technical requirement and the incidence of postoperative complication, the optimal method remains controversial.

METHODS

This study was a single-center, prospective, randomized trial to investigate the utility of lymphadenectomy along the LRLN during the minimally invasive esophagectomy in esophageal squamous cell carcinoma patients by comparing the surgical outcome, postoperative complication, survival rate, and quality of life (QoL) between the retraction method (RM) and the suspension method (SM) in patients with esophageal cancer from June 2018 to November 2020. QoL was assessed according to questionnaire: EQ-5D-5L.

RESULTS

Of 94 patients were enrolled and randomized allocated to RM and SM group equally. Characteristics did not differ between groups. The duration of lymph node dissection along LRLN was significant longer in SM group ( P <0.001). No difference was observed about postoperative complications. One of in-hospital death was occurred in each group ( P >0.999). Patients in neither of groups exhibiting difference about 3-year disease-free survival rate ( P =0.180) and overall survival rate ( P =0.430). No difference was observed in postoperative QoL between groups at different time points (all, P >0.05).

CONCLUSION

Both methods of lymph node dissection along the LRLN during minimally invasive esophagectomy in esophageal squamous cell carcinoma patients are technically feasible and safe. The RM appears more favorable in terms of reducing surgical duration compared to the SM.

Improvement Effect of Upper Mediastinal Lymphadenectomy During Minimally Invasive Esophagectomy on the Prognosis in Squamous Cell Carcinoma: Efficacy Index and Propensity Score Matching Analyses

BACKGROUND

The effect of lymphadenectomy around the recurrent laryngeal nerve (RLN) in open esophagectomy has been demonstrated with the efficacy index (EI). However, it remains unclear whether this effect exists for minimally invasive esophagectomy (MIE) in the prone position. The purpose of this study was to clarify whether the upper mediastinal lymphadenectomy contributed to improved prognosis in patients with esophageal squamous cell carcinoma.

STUDY DESIGN

This study included 339 patients with esophageal squamous cell carcinoma treated with MIE in the prone position at Kobe University or Hyogo Cancer Center, Japan, from 2010 to 2015. EIs for each station, correlations between metastatic lymph nodes around the left RLN and RLN palsy, and survival of patients with and without upper mediastinal lymphadenectomy were investigated.

RESULTS

Among 297 patients treated with upper mediastinal lymphadenectomy, Clavien- Dindo grade ≥ II left RLN palsy occurred in 59 patients (20%). Overall, EIs for the right RLN (7.4) and left RLN (6.6) were higher than EIs for other stations. For patients with upper-third or middle-third tumors, the trend was stronger. Left RLN palsy was more likely in patients with metastatic lymph nodes around the left RLN than in those without (44% vs 15%, p < 0.0001). After propensity score-matching, 42 patients were included in each group with and without upper mediastinal lymphadenectomy. In survival analyses, the 5-year overall survival rates were 55% vs 35% and cause-specific survival rates were 61% vs 43% for the patients with and without upper mediastinal lymphadenectomy respectively. Significant differences were confirmed in survival curves (overall survival: p = 0.03; cause-specific survival: p = 0.04, respectively).

CONCLUSIONS

Upper mediastinal lymphadenectomy contributes to improved prognosis with high EIs in MIE in the prone position.

A Prospective Study Evaluating the Feasibility and Accuracy of Post-operative Laryngeal Ultrasonography (LUSG) in Assessment of Vocal Cord Function After Esophagectomy

BACKGROUND

Vocal cord paresis (VCP) is a serious complication after esophagectomy. Conventional diagnosis of VCP relies on flexible laryngoscopy (FL), which is invasive. Laryngeal ultrasonography (LUSG) is non-invasive and convenient. It has provided accurate VC evaluation after thyroidectomy but it is unclear if it is just as accurate following esophagectomy. This prospective study evaluated the feasibility and accuracy of LUSG in VC assessment on day-1 after esophagectomy.

METHODS

Consecutive patients from a tertiary teaching hospital who underwent elective esophagectomy were prospectively recruited. All received pre-operative FL, and post-operative LUSG and FL on Day-1, each performed by a blinded, independent assessor. The primary outcomes were feasibility and accuracy of LUSG in the diagnosis of VCP on Day-1 post-esophagectomy. The accuracy of voice assessment (VA) was analyzed.

RESULTS

Twenty-six patients were eligible for analysis. The median age was 70 years (66-73). Majority were male (84.6%). Twenty-five (96.2%) received three-phase esophagectomy. Twenty-four (96%) had same-stage anastomosis at the neck. Three (11.5%) developed temporary and one (3.8%) developed permanent unilateral VCP. Overall VC visualization rate by LUSG was 100%; sensitivity, specificity, positive predictive value, negative predictive value (NPV) and accuracy of LUSG were 75.0%, 100%, 100%, 98.0%, 98.1% respectively, and superior to VA. Combining LUSG with VA findings could pick up all VCPs i.e. improved sensitivity and NPV to 100%.

CONCLUSION

LUSG is a highly feasible, accurate and non-invasive method to evaluate VC function early after esophagectomy. Post-operative FL may be avoided in patients with both normal LUSG and voice.

Application of Intraoperative Neuromonitoring (IONM) of the Recurrent Laryngeal Nerve during Esophagectomy: A Systematic Review and Meta-Analysis

BACKGROUND

recurrent laryngeal nerve palsy (RLNP) is a common and severe complication of esophagectomy in esophageal cancer (EC). Several studies explored the application of intraoperative neuromonitoring (IONM) in esophagectomy to prevent RLNP. The purpose of this study was to conduct a systematic review and meta-analysis to evaluate the value of IONM in esophagectomy for EC.

METHODS

an electronic of the literature using Google Scholar, PubMed, Embase, and Web of Science (data up to October 2022) was conducted and screened to compare IONM-assisted and conventional non-IONM-assisted esophagectomy. RLNP, the number of mediastinal lymph nodes (LN) dissected, aspiration, pneumonia, chylothorax, anastomotic leakage, the number of total LN dissected, postoperative hospital stay and total operation time were evaluated using Review Manager 5.4.1.

RESULT

ten studies were ultimately included, with a total of 949 patients from one randomized controlled trial and nine retrospective case-control studies in the meta-analysis. The present study demonstrated that IONM reduced the incidence of RLNP(Odds Ratio (OR) 0.37, 95% Confidence Interval (CI) 0.26-0.52) and pneumonia (OR 0.58, 95%CI 0.41-0.82) and was associated with more mediastinal LN dissected (Weighted Mean Difference (WMD) 4.75, 95%CI 3.02-6.48) and total mediastinal LN dissected (WMD 5.47, 95%CI 0.39-10.56). In addition, IONM does not increase the incidence of aspiration (OR 0.4, 95%CI 0.07-2.51), chylothorax (OR 0.55, 95%CI 0.17-1.76), and anastomotic leakage (OR 0.78, 95%CI 0.48-1.27) and does not increase the total operative time (WMD -12.33, 95%CI -33.94-9.28) or postoperative hospital stay (WMD -2.07 95%CI -6.61-2.46) after esophagectomy.

CONCLUSION

IONM showed advantages for preventing RLNP and pneumonia and was associated with more mediastinal and total LN dissected in esophagectomy. IONM should be recommended for esophagectomy.

Short- and long-term outcomes of thoracoscopic esophagectomy in the prone position for esophageal squamous cell carcinoma in patients with obstructive ventilatory disorder: a propensity score-matched study

BACKGROUND

Many patients with esophageal squamous cell carcinoma (ESCC) have obstructive ventilatory disorder (OVD), which is considered a risk factor for postoperative pneumonia. It has been reported that thoracoscopic esophagectomy in the prone position (TEP) is less invasive and is associated with fewer postoperative respiratory complications compared with open esophagectomy. This matched-cohort study aimed to elucidate the safety and oncologic outcomes of ESCC patients with OVD who undergo TEP.

METHODS

In this matched-cohort study, 237 patients with ESCC who underwent TEP between 2010 and 2018 were divided into two groups based on forced expiratory volume in 1 s/forced vital capacity. Postoperative complications (Clavien-Dindo classification grade II or higher), overall survival (OS), and disease-free survival (DFS) were compared between the two groups.

RESULTS

Based on their propensity scores, 75 patients with normal respiratory function (NRF) and 75 with OVD were selected. The rates of postoperative pneumonia were not significantly different between the two groups (NRF group vs OVD group: 18.7% vs 18.7%; P = 1.000). The rates of recurrent laryngeal nerve palsy and anastomotic leakage were also not significantly different (NRF group vs OVD group: 12.0% vs 18.7%, P = 0.365; 18.7% vs 18.7%, P = 1.000). The 5-year OS and DFS rates in the NRF vs OVD groups were 66.2% vs 54.9% and 63.5% vs 52.9%, respectively, with no significant differences (P = 0.421, 0.197).

CONCLUSIONS

TEP can be safely performed on ESCC patients with OVD and can result in an oncological efficiency equal to that of the NRF group.

Continuous Recurrent Laryngeal Nerve Monitoring During Single-Port Mediastinoscopic Radical Esophagectomy for Esophageal Cancer

BACKGROUND

Although single-port mediastinoscopic radical esophagectomy is ultimate minimally invasive surgery for esophageal cancer without thoracotomy or the thoracoscopic approach, the high incidence of recurrent laryngeal nerve (RLN) palsy remains a pivotal clinical issue.

METHODS

This study included 41 patients who underwent single-port mediastinoscopic radical esophagectomy with mediastinal lymphadenectomy between September 2014 and March 2022. Among these, continuous nerve monitoring (CNM) for RLN was done in 25 patients (CNM group), while the remaining 16 patients underwent without CNM (non-CNM group). Clinical benefits of CNM for RLN were evaluated.

RESULTS

The overall incidence of postoperative RLN palsy was 14.6% (6/41). The CNM group showed a significantly lower incidence of postoperative RLN palsy as compared to the non-CNM group (P = 0.026: CNM vs. non-CRNM: 4.0% (1/25) vs. 31.2% (5/16)). The CNM group had a lower incidence of postoperative pneumoniae (CNM vs. non-CNM: 4.0% (1/25) vs. 18.8% (3/16)) and shorter days of postoperative hospital stay (CNM vs. non-CNM: 13 days vs. 41 days). Multivariate analysis revealed that the CNM use (odds ratio 0.07; 95% CI 0.05-0.98) was an independent factor avoiding postoperative RLN palsy.

CONCLUSION

The CNM for RLN contributes to a remarkable reduction in the risk of postoperative RLN palsy and improvement in outcomes in single-port mediastinoscopic radical esophagectomy.

A novel nomogram predicting the risk of postoperative pneumonia for esophageal cancer patients after minimally invasive esophagectomy

BACKGROUND

Pneumonia is a common complication after minimally invasive esophagectomy (MIE), which prolongs hospital stay, adding to the cost and increasing the risk to patients' lives. This study aimed to identify risk factors and establish a predictive nomogram for postoperative pneumonia (PP).

METHODS

This case control study included 609 patients with esophageal cancer who underwent MIE between March 2015 and August 2019 in Cancer Hospital, Chinese Academy of Medical Sciences. We randomly divided the data into training and validation sets in the ratio of 7:3 and performed univariate and multivariate logistic regression analyses to acquire independent risk factors of the training set. We constructed a nomogram based on the independent risk factors. The concordance index (C-index), receiver operating characteristic (ROC) curve, calibration plot, and decision curve analysis (DCA) plots were used to evaluate the discrimination of the nomogram. Validation set was applied to confirm the predictive value of the nomogram.

RESULTS

In the univariate analysis, age, gender, abdominal procedure method, thoracic operative time, duration of chest tube placement, anastomotic leakage, and recurrent laryngeal nerve palsy were found to be correlated with the incidence of PP. In multivariate analysis, all variables except thoracic operative time were found to be independent risk factors for PP. A nomogram was constructed based on these independent risk factors. The C-index of the training and validation sets was 0.769 and 0.734, respectively, and the areas under the curve (AUC) of ROC curves of the training and validation sets were 0.769 and 0.686, respectively. The calibration plots and DCA plots of the training and validation sets showed the accuracy and predictive value of the nomogram.

CONCLUSION

The nomogram could accurately identify the risk factors for PP. We could predict the occurrence of PP based on this nomogram and take corresponding measures to reduce the incidence of PP.

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.

Comprehensive complication index as a prognostic factor in minimally invasive esophagectomy for esophageal squamous cell carcinoma

BACKGROUND

Postoperative complications affect long-term prognosis in patients with esophageal squamous cell carcinoma (ESCC). Although a comprehensive estimator can predict long-term prognosis, the Clavien-Dindo classification system, a widely used approach to evaluate complications, assesses each complication individually. We aimed to clarify the utility of the comprehensive complication index (CCI) on predicting the overall survival (OS) of patients with ESCC following minimally invasive esophagectomy (MIE).

METHODS

This was a retrospective study of patients undergoing MIE for ESCC in the prone position between January 2011 and December 2018. Multivariate analyses using the Cox proportional hazards model were performed to determine independent risk factors for OS.

RESULTS

The study cohort included 229 patients who were categorized into patients with CCI values of ≥ 33.7 (CCI high) and < 33.7 (CCI low) by receiver-operating characteristic (ROC) curve analysis. There were no significant differences between the two groups according to clinicopathological factors, such as sex, age, tumor location, tumor depth, lymph node metastasis, and neoadjuvant chemotherapy. The intraoperative transfusion rate in the CCI high group was significantly higher than in the CCI low group. The 5 year OS rate was significantly lower in the CCI high group than in the CCI low group (49.5% vs. 65.7%, p = 0.030). By multivariate analyses, age, tumor depth, lymph node metastasis, and the CCI were independent predictors of OS.

CONCLUSIONS

Comprehensive assessment of postoperative complications using the CCI was useful in predicting OS of patients undergoing MIE for the ESCC.

Intraoperative nerve monitoring during esophagectomy reduces the risk of recurrent laryngeal nerve palsy

BACKGROUND

Despite the risk of recurrent laryngeal nerve (RLN) palsy during esophagectomy, no established method of monitoring RLN injury is currently available.

METHODS

This study included 187 patients who underwent esophagectomy between 2011 and 2018. Among these, intraoperative nerve monitoring (IONM) was done in 142 patients (IONM group), while the remaining 45 patients underwent conventional surgery without IONM (control group). We investigated the incidence of postoperative complications with regard to the use of IONM.

RESULTS

The overall incidence of postoperative RLN palsy was 28% (52/187). The IONM group showed a significantly lower incidence of postoperative RLN palsy as compared to that in the control group (p = 0.004). The overall incidence of postoperative pneumonia was 22% (41/187) in those with Clavien-Dindo (CD) classification beyond grade 2. There were no significant differences between the incidence of any grade of postoperative pneumonia and the use of IONM (p = 0.195 and 0.333; CD > 2 and > 3, respectively). Multivariate analysis demonstrated that tumors in the upper third [odds ratio (OR) 3.12; 95% confidence interval (CI) 1.04-9.29] and lack of IONM use (OR 2.51; 95% CI 1.17-5.38) were independent factors causing postoperative RLN palsy after esophagectomy.

CONCLUSION

IONM helps to reduce the risk of postoperative RLN palsy after esophageal cancer surgery.

A comparison of the surgical invasiveness and short-term outcomes between thoracoscopic and pneumatic mediastinoscopic esophagectomy for esophageal cancer

PURPOSE

Minimally invasive esophagectomy (MIE) has been widely accepted as a treatment for esophageal cancer. This retrospective study compared the short-term outcomes and surgical invasiveness between thoracoscopic esophagectomy (TE) and mediastinoscopic esophagectomy with pneumomediastinum (pneumatic mediastinoscopic esophagectomy [PME]).

METHODS

A total of 72 patients who underwent TE or PME were included and assessed for their surgical findings, postoperative complications, and inflammatory responses on postoperative day (POD) 1, 3, 5, and 7.

RESULTS

The PME group exhibited a significantly shorter operative time and fewer lymph nodes retrieved than the TE group. Furthermore, the PME group tended to have greater incidences of recurrent laryngeal nerve palsy and lower incidences of atelectasis than the TE group. The PME group had significantly lower white blood cell counts on POD 5, serum C-reactive protein (CRP) levels on POD 3 than the TE group.

CONCLUSION

PME seems to be less invasive than TE and can be considered the preferred option for patients with lower-stage esophageal cancer expected to have severe pleural adhesion or who cannot tolerate TE.

AQP9 and ZAP70 as immune-related prognostic biomarkers suppress proliferation, migration and invasion of laryngeal cancer cells

BACKGROUND

Laryngeal cancer represents a common malignancy that originates from the larynx, with unfavorable prognosis. Herein, this study systematically analyzed the immune signatures of laryngeal cancer and to evaluate their roles on tumor progression.

METHODS

Differentially expressed immune-related genes (IRGs) were screened between laryngeal cancer and normal tissues from TCGA dataset. Then, two prognosis-related IRGs AQP9 and ZAP70 were analyzed by a series of survival analysis. Based on them, molecular subtypes were constructed by unsupervised cluster analysis. Differences in survival outcomes, HLA expression and immune cell infiltrations were assessed between subtypes. Expression of AQP9 and ZAP70 was validated in laryngeal cancer tissues and cells by RT-qPCR and immunohistochemistry. After silencing and overexpressing AQP9 and ZAP70, CCK-8, EdU, wound healing and transwell assays were performed in TU212 and LCC cells.

RESULTS

Totally, 315 IRGs were abnormally expressed in laryngeal cancer. Among them, AQP9 and ZAP70 were distinctly correlated to patients' prognosis. Two subtypes were developed with distinct survival outcomes, HLA expression and immune microenvironment. Low expression of AQP9 and ZAP70 was confirmed in laryngeal cancer. AQP9 and ZAP70 up-regulation distinctly suppressed proliferation, migration, and invasion of laryngeal cancer cells. The opposite results were investigated when their knockdown.

CONCLUSIONS

Our findings revealed the roles of AQP9 and ZAP70 in progression of laryngeal cancer, and suggested that AQP9 and ZAP70 could potentially act as candidate immunotherapeutic targets for laryngeal cancer.

Double-lumen tube versus bronchial blocker in lymphadenectomy along the left recurrent laryngeal nerve for esophageal cancer: a propensity-matched analysis

BACKGROUND

Lymph node (LN) dissection along left recurrent laryngeal nerve (RLN) is challenging in esophagectomy for esophageal cancer, and double-lumen endotracheal tube (DLT) impedes the exposure of this area. The aim of this study was to determine whether bronchial blockers (BB) could be a better choice for this procedure.

METHODS

The clinical characteristics of patients who received McKeown esophagectomy with radical lymph node dissection in Wuhan Tongji Hospital between August 2017 and July 2019 were retrospectively analyzed. The 1:1 propensity score match analysis was performed to compare the short-term effectiveness, the numbers of lymph nodes dissected, and the patterns of recurrence and survival between the two groups.

RESULTS

A total of 294 patients (192 and 102 in the DLT and BB group, respectively) were enrolled in the study. After matching, 204 patients (102 pairs) who underwent one-lung ventilation with DLT or BB displayed no significant variance in baseline characteristics. The BB group had higher number of LNs resected along left RLN (1.8 ± 2.3 vs. 2.5 ± 2.5, P = 0.001). For patients with metastatic left RLN LN, the BB group had longer medium survival time (15 vs. 32 months, P = 0.045), and tended to have longer medium recurrence-free survival time (6 vs. 15 months, P = 0.079), and lower rate of upper mediastinal and cervical LN recurrence (30.00% vs. 66.67%, P = 0.198). The postoperative complications were similar in both groups.

CONCLUSIONS

Compared with DLT, using BB in esophagectomy may allow more radical lymphadenectomy along left RLN.

Impact of prior thoracoscopic experience on the learning curve of robotic McKeown esophagectomy: a multidimensional analysis

PURPOSE

Left upper mediastinal lymph node dissection (UMLND)-a technically demanding step of McKeown esophagectomy-is frequently complicated by recurrent laryngeal nerve (RLN) palsy. Under the hypothesis that robotic esophagectomy (RE) could increase the safety and feasibility of UMLND, we retrospectively investigated the degree to which a pre-existing experience in video-assisted thoracoscopic esophagectomy (VATE) may affect the learning curves of this critical part of RE.

METHODS

Surgeon A had previously performed > 150 VATE procedures before transitioning to RE. While surgeon B had previously assisted to 50 RE, his pre-existing VATE experience consisted of less than five procedures. A total of 103 and 76 McKeown RE procedures were performed by surgeons A and B, respectively. The learning curve of left UMLND for each surgeon was examined using the cumulative sum method.

RESULTS

The inflection point of RLN palsy for surgeon A occurred at patient 31. While the nerve palsy rate decreased from 32.3 to 4.2% (p < 0.001), the number of nodes harvested during left UMLND did not appreciably change. Surgeon B showed a bimodal learning curve for RLN palsy with primary and secondary inflection points at patients 15 and 49, respectively. The RLN palsy rate initially decreased from 66.7% (patients 1-15) to 14.7% (patients 16-49), followed by an additional decline to 3.7% (patients 50-76). However, the number of nodes harvested during left UMLND showed a downtrend which was paralleled by decreasing rates of RLN palsy. These results indicate that surgeon B has not yet reached an ideal balance between an extensive UMLND and nerve protection.

CONCLUSION

The pre-existing VATE experience seems to affect the learning curves of left UMLND during RE.

Recurrent Nerve Injury After Total Thyroidectomy: Risk Factor Analysis of a Targeted NSQIP Data Set

BACKGROUND

Recurrent laryngeal nerve (RLN) injury is a significant complication after thyroidectomy. Understanding risk factors for RLN injury and the associated postoperative complications may help inform quality improvement initiatives.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) thyroidectomy-targeted database was utilized for patients undergoing total thyroidectomy between 2016 and 2017. Univariable and multivariable regression were used to identify factors associated with RLN injury.

RESULTS

A total of 6538 patients were identified. The overall rate of RLN injury was 7.1% (467/6538). Of these, 4129 (63.1%) patients had intraoperative neuromonitoring (IONM), with an associated RLN injury rate of 6.5% (versus 8.2% without). African American and Asian race, non-elective surgery, parathyroid auto-transplantation, and lack of RLN monitoring were all significantly associated with nerve injury on multivariable analysis (P<.05). Patients with RLN injury were more likely to experience cardiopulmonary complications, re-intubation, longer length of stay, readmission, and reoperation. Patients who had IONM and sustained RLN injury remained at risk for developing significant postoperative complications, although the extent of cardiopulmonary complications was less severe in this cohort.

DISCUSSION

Recurrent laryngeal nerve injury is common after thyroidectomy and is associated with significant morbidity, despite best practices. Attention to preoperative characteristics may help clinicians to further risk stratify patients prior to thyroidectomy. While IONM does not mitigate all complications, use of this technology may decrease severity of postoperative complications.

Clinical outcome of patients after recurrent laryngeal nerve lymph node dissection for oesophageal squamous cell carcinoma

 

OBJECTIVES

Recurrent laryngeal nerve lymph node dissection (LND) has been incorporated into oesophagectomy for patients with oesophageal squamous cell carcinoma, but with uncertain oncological efficacy.

METHODS

The data of patients with oesophageal squamous cell carcinoma, including who underwent upfront surgery (surgery group) and those who received neoadjuvant therapy followed by surgery (neoadjuvant chemoradiotherapy group), were retrospectively examined. The overall survival (OS) and disease-free survival (DFS) were compared between patients with and without recurrent laryngeal nerve LND.

RESULTS

Among the 312 patients, no significant differences were found in 3-year OS and DFS between patients with and without recurrent laryngeal nerve LND in the entire cohort (OS: 57% vs 52%, P = 0.33; DFS: 47% vs 41%, P = 0.186), or the surgery group (n = 173, OS: 69% vs 58%, P = 0.43; DFS: 52% vs. 48%, P = 0.30) and the neoadjuvant chemoradiotherapy group (n = 139, OS: 44% vs 43%, P = 0.44; DFS: 39% vs 32%, P = 0.27). However, among patients with clinical positive recurrent laryngeal nerve lymph node involvement before treatment, there was significant OS and DFS differences between patients with and without recurrent laryngeal nerve LND (OS: 62% vs 33%, P = 0.029; DFS: 49% vs 26%, P = 0.031).

CONCLUSIONS

Recurrent laryngeal nerve LND is not a significant prognostic factor in patients with oesophageal squamous cell carcinoma; however, it is associated with better outcomes in patients with pre-treatment radiological evidence of recurrent laryngeal nerve lymph node involvement.

Improving Outcome of Superior Mediastinal Lymph Node Dissection During Esophagectomy: A Novel Approach Combining Continuous and Intermittent Recurrent Laryngeal Nerve Monitoring

OBJECTIVE

This study aimed at demonstrating the effects and learning curve of utilizing combined intermittent and continuous recurrent laryngeal nerve (RLN) monitoring for lymphadenectomy during esophagectomy.

BACKGROUND

RLN lymphadenectomy is oncologically important but is technically demanding. Vocal cord (VC) palsy as a result from RLN injury, carries significant morbidities.

METHODS

This is a retrospective study of consecutive esophageal squamous cell carcinoma (ESCC) patients who underwent transthoracic esophagectomy from 2010 to 2020. Combined nerve monitoring (CNM) included: CNM which involved a periodic stimulating left vagal electrode and intermittent nerve monitoring which utilized a stimulating probe to identify the RLNs. The integrity of the RLNs was assessed both intermittently and continuously. This technique was introduced in 2014. Patients were divided into "before CNM" and "CNM" groups. The primary outcome was the difference in number of RLN lymph nodes harvested and VC palsy rate. Learning curves were demonstrated by cumulative sum (CUSUM) analysis.

RESULTS

Two hundred and fifty-five patients were included with 157 patients in "CNM" group. The mean number of RLN lymph nodes harvested was significantly higher (4.31 vs 0.45, P < 0.0001) for the "CNM" group. VC palsy rates were significantly lower (17.8% vs 32.7%, P = 0.007). There was an initial increase in VC palsy rate, peaked at around 46 cases. The increase in lymph nodes harvested above the mean plateaued at around 96 cases.

CONCLUSIONS

CNM helped improve bilateral RLN lymphadenectomy. Lymph node harvesting was increased with reduction of VC palsy after a learning curve.

Clinical usefulness of sputum culture on the first postoperative day to predict early postoperative pneumonia after esophagectomy for esophageal cancer

BACKGROUND

Postoperative pneumonia is a serious prognostic problem that can appear after esophagectomy in patients with esophageal cancer. The past reports have considered the usefulness of perioperative culture examinations for predicting postoperative pneumonia; however, the direct relationship between these examinations and postoperative complications remains unclear.

METHODS

This study retrospectively analyzed esophageal cancer patients who underwent esophagectomy followed by sputum culture on the first postoperative day. The bacterial species that frequently cause hospital-acquired pneumonia were chosen as the target species in this study. The relationship between culture examination and postoperative pneumonia within one week (7 days) after esophagectomy was investigated.

RESULTS

Sputum cultures on the first postoperative day were investigated in 238 patients who underwent esophagectomy for esophageal cancer. Forty-one patients developed pneumonia within one week after surgery. The target bacterial species were detected in 26 of 238 sputum cultures (10.9%). In the univariate analysis, a Brinkman index, detection of target bacterial species, detection of Gram-positive cocci, and Gram-negative rods were significantly associated with postoperative pneumonia. In the three independent multivariate analyses, the target bacterial species, Gram-positive cocci, and Gram-negative rods (p = 0.001, 0.042, and < 0.001) were individually identified as independent risk factors of postoperative pneumonia in addition to a Brinkman index.

CONCLUSIONS

Detection of target bacterial species by sputum culture on the first postoperative day after esophagectomy was an independent risk factor of postoperative pneumonia within 7 days after surgery. Prospective studies for the prevention of early postoperative pneumonia using sputum culture on the first postoperative day can be considered.

Mediastinal anatomical landmarks, their variants and tips for video-assisted thoracoscopic navigation during oesophageal extirpation

Purpose

There is no systematic description of primary anatomical landmarks that allow a surgeon to reliably and safely navigate the superior and posterior mediastinum’s fat tissue spaces near large vessels and nerves during video-assisted endothoracoscopic interventions in the prone position of a patient. Our aim was to develop an algorithm of sequential visual navigation during thoracoscopic extirpation of the esophagus and determine the most permanent topographic and anatomical landmarks allowing safe thoracoscopic dissection of the esophagus in the prone position.

Methods

The anatomical study of the mediastinal structural features was carried out on 30 human cadavers before and after opening the right pleural cavity.

Results

For thoracoscopic extirpation of the esophagus in the prone position, anatomical landmarks are defined, their variants are assessed, and an algorithm for their selection is developed, allowing their direct visualization before and after opening the mediastinal pleura.

Conclusion

The proposed algorithm for topographic and anatomical navigation based on the key anatomical landmarks in the posterior mediastinum provides safe performance of the video-assisted thoracoscopic extirpation of the esophagus in the prone position.

Incidence of Recurrent Laryngeal Nerve Palsy in Robot-Assisted Versus Conventional Minimally Invasive McKeown Esophagectomy in Prone Position: A Propensity Score-Matched Study

BACKGROUND

Esophagectomy with lymphadenectomy is the principal treatment for localized esophageal cancer. Conventional minimally invasive esophagectomy (C-MIE) in prone position has spread worldwide as it is less invasive. However, its efficacy remains controversial. Robot-assisted MIE (RAMIE) can have more advantages than C-MIE. Therefore, the current study aimed to validate whether RAMIE is associated with lower incidence of left recurrent laryngeal nerve (RLN) palsy compared with C-MIE in prone position.

PATIENTS AND METHODS

In total, 404 patients with esophageal carcinoma underwent MIE (353 C-MIEs and 51 RAMIEs) in prone position at Kobe University between 2010 and 2020. Then, propensity score matching was performed, and results showed that 51 patients should be included in each group. Thereafter, the perioperative outcomes between the two groups were compared.

RESULTS

The RAMIE group had a significantly longer operative time than the C-MIE group (P < 0.0001). However, the number of lymph nodes resected along the left RLN was similar in both groups. Moreover, the incidence of left RLN palsy was significantly lower in the RAMIE group than in the C-MIE [Clavien-Dindo classification grade II; 0 (0%) versus 32 (9%), P = 0.022 in entire cohort, and 0 (0%) versus 5 (10%), P = 0.022 in matched cohort. Esophagectomy Complications Consensus Group definitions type I; 8 (16%) versus 101 (29%), P = 0.041 in entire cohort and 8 (16%) versus 18 (35%) in matched cohort, P = 0.023].

CONCLUSION

RAMIE is superior to C-MIE in prone position in decreasing the incidence of left RLN palsy.

Airflow Limitation Predicts Postoperative Pneumonia after Esophagectomy

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is known to be a risk factor of pneumonia after esophagectomy. In this study, we investigated the relationship of airflow limitation with the occurrence and the severity of pneumonia in esophageal cancer patients who underwent esophagectomy.

METHODS

We enrolled 844 patients who underwent curative esophagectomy between 2009 and 2018. The airflow limitation was evaluated using the percent-predicted forced expiratory volume at 1 s (%FEV1) with spirometry.

RESULTS

There were 597 (70.7%), 141 (16.7%), 68 (8.1%), and 38 patients (4.5%) with %FEV1 of ≥ 90%, 80-90%, 70-80%, and < 70% categories, respectively. One hundred and ninety-one patients (22.6%) occurred pneumonia, and the incidences of pneumonia in each category of patients were 18.8%, 28.4%, 29.4%, and 50.0%, respectively. In multivariate analysis, the categories of 80%-90%, 70-80%, and < 70% were significantly associated with a higher incidence of postoperative pneumonia (OR 1.57; 95% CI 1.02-2.43, OR 1.87; 95% CI 1.04-3.36, OR 3.34; 95% CI 1.66-6.71, respectively), with the %FEV1 category of ≥ 90% as reference. The incidence of severe pneumonia of Clavien-Dindo grade III or higher was also significantly associated with the %FEV1. In patients without COPD, the incidence of pneumonia was significantly higher in those with %FEV1 < 90% than in those with %FEV1 ≥ 90% (32.2% versus 17.5%, p < 0.001).

CONCLUSIONS

The airflow limitation can help predict the occurrence of pneumonia after esophagectomy in patients with and without COPD. Exclusive preventive measures should be considered in patients with reduced %FEV1 undergoing esophagectomy.

Postoperative pneumonia in the acute phase is an important prognostic factor in patients with esophageal cancer

BACKGROUND

The impact of pneumonia on prognosis is controversial, and no report has focused on its onset. This study aimed to examine the impact of pneumonia according to its onset on prognosis and its associated risk factors after esophagectomy.

METHODS

In total, 484 patients who underwent curative resection for esophageal squamous cell carcinoma were retrospectively reviewed. Patients with pneumonia were divided into two groups by the date of onset: pneumonia in the acute phase within 7 days after surgery (n = 59) and pneumonia in the subacute phase 8 days after surgery (n = 49).

RESULTS

The disease-free survival of patients with acute pneumonia was significantly lower than that of those without pneumonia (P = .0002), whereas the disease-free survival of patients with subacute pneumonia was similar to that of patients without pneumonia (P = .5363). In multivariate analysis for disease-free survival, P-stage III to IV (hazard ratio [HR], 3.344; P < .0001), transfusion (HR, 1.4078; P = .0291), and acute pneumonia (HR, 1.8463; P = .0009) were independent prognostic factors. Multivariate analysis revealed that age >75 years (odds ratio [OR], 2.1746; P = .0232), respiratory disease comorbidity (OR, 4.3869; P = .0002), cT3-4 (OR, 2.0143; P = .0477), extended surgery duration (OR, 2.3406; P = .0152), and posterior mediastinal reconstruction (OR, 0.1432; P = .0439) were independent risk factors for acute pneumonia.

CONCLUSION

Post-esophagectomy pneumonia in the acute phase was an independent prognostic factor, whereas advanced age, respiratory disease comorbidity, and extended surgery duration were risk factors for acute pneumonia.

Novel "Modified Bascule Method" for Lymphadenectomy Along the Left Recurrent Laryngeal Nerve During Robot-Assisted Minimally Invasive Esophagectomy

BACKGROUND

Given the worldwide popularization of conventional minimally invasive esophagectomy (C-MIE), robot-assisted MIE (RAMIE) can be expected to provide a finer procedure. However, controversy remains regarding whether RAMIE is superior to C-MIE in preventing recurrent laryngeal nerve (RLN) palsy. Considering the shallow learning curve for RAMIE, a novel procedure for lymphadenectomy along the RLN during RAMIE is needed.

METHODS

Based on a logical and simple understanding of the left upper mediastinum anatomy, the authors developed a novel "modified bascule method" for RAMIE that could simplify lymphadenectomy along the left RLN and prevent it from being touched and stretched. Between 2018 and 2020, 46 patients with esophageal carcinoma underwent RAMIE using this method at Kobe University.

RESULTS

The modified bascule method was used to perform RAMIE for 29 men and 17 women with a median age of 67 years (range, 49-82 years). The median thoracoscopic procedure time was 438 min (range, 344-625 min), and the median console time was 351 min (range 273-518 min). The study harvested a median of 24 (range, 8-34) lymph nodes from the thoracic portion and 4 (range, 0-10) lymph nodes from along the left RLN. The mortality rate was 0%. Postoperative left RLN palsy classified as Clavien-Dindo (C-D) grade 1 or higher was observed for 9 patients (19%), whereas grade 2 or higher was not seen (0%). Pneumonia and anastomotic leakage rates higher than C-D grade 2 were respectively 13% and 19%.

CONCLUSIONS

The novel modified bascule method for RAMIE can promote feasible lymphadenectomy along the left RLN even when performed during the learning period.

A standardized procedure for upper mediastinal lymph node dissection improves the safety and efficacy of robotic McKeown oesophagectomy

BACKGROUND

Recurrent laryngeal nerve (RLN) palsy is a common complication of upper mediastinal lymph node dissection (UMLND) in the context of oesophageal cancer surgery. In an effort to reduce its occurrence, we developed a standardised surgical procedure that allows flexible suspension of the left RLN during robotic McKeown oesophagectomy.

PATIENTS AND METHODS

Patients who received robotic McKeown oesophagectomy for cancer were divided into two groups (pre and poststandardisation). Perioperative outcomes were retrospectively compared.

RESULTS

The pre and poststandardisation groups consisted of 44 and 42 patients, respectively. There were no significant intergroup differences in terms of number of dissected lymph nodes. Compared with the prestandardisation group, patients treated after standardisation had a markedly lowered incidence of left RLN palsy (20.5% vs. 4.8%, respectively, p = 0.029) and a reduced mean thoracic operating time (161.05 vs. 131 min, respectively, p < 0.001).

CONCLUSION

Our standardised surgical approach is efficient and may increase the safety of UMLND.

Three-dimensional visualization system is one of the factors that improve short-term outcomes after minimally invasive esophagectomy

PURPOSE

Minimally invasive esophagectomy (MIE) has been increasingly used, but many reports have stated that recurrent laryngeal nerve (RLN) palsy after MIE is a major complication associated with postoperative pneumonia. Prevention of RLN palsy clearly has been a challenging task. The study aim was to determine if a three-dimensional (3-D) stereoscopic vision system can reduce the RLN palsy rate after MIE.

METHODS

This was a retrospective study of MIE (McKeown esophagectomy) using a 3-D or 2-D stereoscopic vision system to treat 358 patients in the prone position between April 2010 and March 2019. The patients who underwent 3-D MIE (3-D group) or 2-D MIE (2-D group) were matched by using propensity score matching. After matching, the perioperative outcomes were compared between the groups.

RESULTS

After propensity score matching, 154 patients were analyzed (77 patients, 3-D group; 77 patients, 2-D group). There were no significant differences in the patients' baseline characteristics in the matched cohort. There were no significant differences in the rates of pneumonia (Clavien-Dindo (C-D) grade ≥ II, 3-D vs. 2-D, 11 (14%) vs. 12 (16%)), anastomotic leakage (C-D grade ≥ II, 10 (13%) vs. 18 (23%)) and mortality. The rates of left RLN palsy (C-D grade ≥ IIIa, 1 (1.3%) vs. 7 (9.1%), P = 0.029), right RLN palsy (C-D grade ≥ I, 2 (3%) vs. 8 (10%), P = 0.049), comprehensive complication index (CCI®) (8.5 vs. 14.3, P = 0.011), and postoperative hospital stay period (median: 25 vs. 30 days, P = 0.034) were significantly lower in the 3-D group than in the 2-D group, respectively.

CONCLUSIONS

In MIE, the 3-D viewing system was one of the factors that reduced postoperative morbidities such as the rates of each RLN palsy and CCI®, leading to shorter postoperative hospital stay.

Recent advances in minimally invasive esophagectomy for squamous esophageal cancer

Over the past decade there has been tremendous development in the clinical application of minimally invasive esophagectomy (MIE) for the treatment of squamous esophageal carcinoma. The major challenges in the performance of MIE include limitations in visualization and manipulation within the confined, rigid thoracic cavity; the need for adequate patient positioning and anesthetic techniques to accommodate the surgical exposure; and changes in the surgical steps for achieving radical nodal dissection, especially for the superior mediastinum. The surgical procedure for MIE is more and more standardized, and there is an increasing practice of MIE worldwide. Randomized trials and meta-analyses have confirmed the advantages of MIE over open esophagectomy, including a significantly lower rate of complications and shorter hospital stays. The recent application of robotics technologies for MIE has further enhanced the quality and safety of the surgical dissection, while intraoperative nerve monitoring has contributed to a lower rate of recurrent laryngeal nerve palsy. With the application of new technologies, we expect further improvement in surgical outcomes for MIE in the treatment of squamous esophageal cancer.

Lymph node dissection and recurrent laryngeal nerve protection in minimally invasive esophagectomy

Until now, neoadjuvant therapy plus surgical resection of the primary tumor and potential metastatic lymph nodes (LNs) has been the current optimal treatment for locally advanced thoracic esophageal cancer (EC). LN metastasis is one of the most negative prognostic factors for thoracic esophageal squamous cell carcinoma (ESCC). However, the extent of LN dissection for thoracic ESCC has long been controversial worldwide. LNs along the recurrent laryngeal nerve (RLN) were reported to have the highest frequency of metastases in thoracic ESCC, so lymphadenectomy along the bilateral RLN is necessary but quite challenging because of a high frequency of recurrent nerve palsy and related postoperative complications. With the development of minimally invasive devices and techniques in recent years, minimally invasive esophagectomy (MIE) has been widely applied in EC surgery. The topics of what the optimal extent of lymphadenectomy is and how the recurrent nerve should be well protected during MIE have been debated in recent years. The purpose of our review is specifically to address the patterns of LN metastasis, the extent of LN dissection, and the protection of the RLN in MIE for thoracic ESCC.