Efficacy of Intraoperative Recurrent Laryngeal Nerve Monitoring During Thoracoscopic Esophagectomy for Esophageal Cancer: A Systematic Review and Meta-Analysis

Recurrent Laryngeal Nerve Intraoperative Neuromonitoring Indications in Non-Thyroid and Non-Parathyroid Surgery

Introperative nerve monitoring (IONM) of the recurrent laryngeal nerve (RLN) is a well-established technique to aid in thyroid/parathyroid surgery. However, there is little evidence to support its use in non-thyroid or non-parathyroid surgery. The aim of this paper was to review the current evidence regarding the use of IONM in non-thyroid/non-parathyroid surgery in the head and neck and thorax. A literature search was performed from their inception up to January 2024, including the term "recurrent laryngeal nerve monitoring". IONM in non-thyroid/non-parathyroid surgery has mainly been previously described in oesophageal surgery and in tracheal resections. However, there is little published evidence on the role of IONM with other resections in the vicinity of the RLN. Current evidence is low-level for the use of RLN IONM in non-thyroid/non-parathyroid surgery. However, clinicians should consider its use in surgery for pathologies where the RLN is exposed and could be injured.

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.

Robotic esophagectomy with outermost layer-oriented dissection for esophageal cancer: technical aspects and a retrospective review of a single-institution database

BACKGROUND

Systematic lymph node dissection in patients with gastric cancer could be sufficiently and reproducibly achieved along the outermost layer of the autonomic nerves and similar concept has been extensively used for robotic esophagectomy (RE) since 2018. This study aimed to determine the surgical and oncological safety of RE using the outermost layer-oriented approach for esophageal cancer (EC).

METHODS

Sixty-six patients who underwent RE with total mediastinal lymphadenectomy for primary EC between April 2018 and December 2021 were retrospectively reviewed. All underwent the outermost layer-oriented approach with intraoperative nerve monitoring (IONM). Postoperative complications within 30 days were analyzed.

RESULTS

Among the patients, 51 (77.3%) were male. The median age was 64 years, and the body mass index was 21.8 kg/m2. Furthermore, 58 (87.9%) patients had squamous cell carcinoma and eight (12.1%) patients had adenocarcinoma. Clinical stages I, II, and III were seen in 23 (34.8%), 23 (34.8%), and 16 (24.2%) patients, respectively. Thirty-four (51.5%) patients received preoperative treatment. No patient shifted to conventional thoracoscopic or open procedure intraoperatively. The median operative time was 716 min with 119 mL of blood loss. Additionally, 64 (97%) patients underwent R0 resection. The morbidity rates based on Clavien-Dindo grades ≥ II and ≥ IIIa were 30.3% and 10.6%, respectively, within 30 postoperative days. None died within 90 days postoperatively. Three (4.5%) patients exhibited recurrent laryngeal nerve (RLN) palsy (CD grade ≥ II). The sensitivity and specificity of IONM for RLN palsy were 50% and 98.3% at the right RLN and 33.3% and 98.0% at the left RLN, respectively.

CONCLUSION

RE with the outermost layer-oriented approach can provide safe short-term outcomes.

Intraoperative Nerve Monitoring during Minimally Invasive Esophagectomy and 3-Field Lymphadenectomy: Safety, Efficacy, and Feasibility

Background

The objective of this study was to demonstrate the safety, efficacy, and feasibility of intraoperative monitoring of the recurrent laryngeal nerves during thoracoscopic and robotic 3-field esophagectomy.

Methods

This retrospective analysis details our initial experience using intraoperative nerve monitoring (IONM) during minimally invasive 3-field esophagectomy. Data were obtained from a prospectively maintained database and electronic medical records. The study included all patients who underwent minimally invasive (video-assisted thoracic surgery/robotic) transthoracic esophagectomy with neck anastomosis. The patients were divided into those who underwent IONM during the study period and a historical cohort who underwent 3-field esophagectomy without IONM at the same institution. Appropriate statistical tests were used to compare the 2 groups.

Results

Twenty-four patients underwent nerve monitoring during minimally invasive 3-field esophagectomy. Of these, 15 patients underwent thoraco-laparoscopic operation, while 9 received a robot-assisted procedure. In the immediate postoperative period, 8 of 24 patients (33.3%) experienced vocal cord paralysis. Relative to a historical cohort from the same institution, who were treated with surgery without nerve monitoring in the preceding 5 years, a 26% reduction was observed in the nerve paralysis rate (p=0.08). On follow-up, 6 of the 8 patients with vocal cord paralysis reported a return to normal vocal function. Additionally, patients who underwent IONM exhibited a higher nodal yield and a decreased frequency of tracheostomy and bronchoscopy.

Conclusion

The use of IONM during minimally invasive 3-field esophagectomy is safe and feasible. This technique has the potential to decrease the incidence of recurrent nerve palsy and increase nodal yield.

Bilateral video-assisted thoracic surgery for esophageal cancer with left inferior pulmonary vein invasion following chemoradiation therapy

BACKGROUND

The surgical strategy for thoracic esophageal cancer that invades the lungs is controversial. In particular, invasion of the pulmonary vein is often regarded unresectable. We successfully applied bilateral video-assisted thoracic surgery (VATS) in esophagectomy for esophageal cancer with left inferior pulmonary vein invasion following induction chemoradiotherapy (CRT), with a favorable response.

CASE PRESENTATION

A 64-year-old woman was diagnosed with squamous cell carcinoma of the lower third of the esophagus. Computed tomography (CT) revealed that the tumor was suspected to be invading the main trunk of the left lower pulmonary vein and left lower lung. We initiated induction CRT comprising 5-fluorouracil, cisplatin, and concurrent radiotherapy at 50.4 Gy/28Fr. CT revealed shrinkage of the tumor, and the main trunk of the left inferior pulmonary vein was released from the tumor invasion. We considered the tumor to be completely resectable. VATS esophagectomy is usually performed using a right-sided approach. However, the right-sided approach is inappropriate for evaluating tumors around the left inferior pulmonary vein. We started with left-sided VATS to determine tumor resectability and dissected between the esophagus and the main trunk of the left inferior pulmonary vein. We only needed to perform partial resection of the left lower lobe. We then performed a right-sided VATS esophagectomy and lymphadenectomy with partial en bloc resection of the left lower lobe. Following this, we performed hand-assisted laparoscopic proximal gastrectomy and reconstruction using the gastric remnant. The postoperative course was uneventful. The patient was discharged on postoperative day 14. Histopathological examination of the surgical specimen revealed a complete pathological response without any remnant tumor or lymph node metastasis. There were no signs of recurrence or metastasis at the 1-year follow-up.

CONCLUSIONS

Curative resection for thoracic esophageal cancer that invades the pulmonary vein could be possible via the bilateral VATS approach following induction CRT with a favorable response.

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.

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 survey of the clinical outcomes of cervical esophageal carcinoma surgery focusing on the presence or absence of laryngectomy using the National Clinical Database in Japan

BACKGROUND

One upside of cervical esophageal carcinoma is that radical surgery can be performed by laryngectomy, even for tumors with tracheal invasion. However, this approach drastically reduces the quality of life, such as by losing the vocal function. Cervical esophageal carcinoma is rare, and no comprehensive reports have described the current state of surgery. Using a Japanese nationwide web-based database, we analyzed the surgical outcomes of cervical esophageal carcinoma to evaluate the impact of larynx-preserving surgery.

METHODS

Based on the Japan National Clinical Database, 215 surgically treated cases of cervical esophageal carcinoma between January 1, 2018, and December 31, 2019, were enrolled. Clinical outcomes were compared between the larynx-preserved group and the laryngectomy group.

RESULTS

Ninety-four (43.7%) patients underwent larynx-preserving surgery. A total of 177 (82.3%) patients underwent free jejunum reconstruction. More T4b patients and more patients who underwent preoperative radiotherapy were in the laryngectomy group. There were no significant differences in the frequency and the severity of morbidities between the two groups. However, in the laryngectomy group, in-hospital death within 30 days after surgery was observed in 1 patient, and the postoperative hospital stay was significantly longer (P = 0.030). In the larynx-preserved group, recurrent nerve paralysis was observed in 24.5%. Re-operation (35.3%, P = 0.016), re-intubation (17.6%, P = 0.019) and tracheal necrosis (17.6%, P = 0.028) were significantly more frequent in patients who underwent pharyngolaryngectomy with total esophagectomy and gastric tube reconstruction than in others.

CONCLUSION

Larynx-preserving surgery was therefore considered to be feasible because it was equivalent to laryngectomy regarding the short-term surgical outcomes.