Pattern of lymph node metastases of squamous cell esophageal cancer based on the anatomical lymphatic drainage system: efficacy of lymph node dissection according to tumor location

Preoperative CT radiomics of esophageal squamous cell carcinoma and lymph node to predict nodal disease with a high diagnostic capability

PURPOSE

To develop CT radiomics models of resectable esophageal squamous cell carcinoma (ESCC) and lymph node (LN) to preoperatively identify LN+.

MATERIALS AND METHODS

299 consecutive patients with ESCC were enrolled in the study, 140 of whom were LN+ and 159 were LN-. Of the 299 patients, 249 (from the same hospital) were randomly divided into a training cohort (n = 174) and a test cohort (n = 75). The remaining 50 patients, from a second hospital, were assigned to an external validation cohort. In the training cohort, preoperative contrast-enhanced CT radiomics features of ESCC and LN were extracted, then integrated with clinical features to develop three models: ESCC, LN and combined. The performance of these models was assessed using area under receiver operating characteristic curve (AUC), and F-1 score, which were validated in both the test cohort and external validation cohort.

RESULTS

An ESCC model was developed for the training cohort utilizing the 8 tumor radiomics features, and an LN model was constructed using 9 nodal radiomics features. A combined model was constructed using both ESCC and LN extracted features, in addition to cT stage and LN+ distribution. This combined model had the highest predictive ability among the three models in the training cohort (AUC = 0.948, F1-score = 0.878). The predictive ability was validated in both the test and external validation cohorts (AUC = 0.885 and 0.867, F1-score = 0.816 and 0.773, respectively).

CONCLUSION

To preoperatively determine LN+, the combined model is superior to models of ESCC and LN alone.

Comparison of TNM AJCC/UICC 8th with JES 11th staging systems for prognostic prediction in patients with esophageal squamous cell carcinoma who underwent radical (chemo) radiotherapy in China

OBJECTIVE

The aim of the study was to compare the prognostic prediction performances of the American Joint Committee on Cancer (AJCC)/Union for International Cancer Control (UICC) 8th staging system and the Japan Esophageal Society (JES) 11th staging system for patients with esophageal squamous cell carcinoma who underwent radical (chemo) radiotherapy.

METHODS

In total, 574 patients were enrolled and categorized according to the tumor, node metastasis (TNM) AJCC/UICC 8th and JES 11th editions. Survival rates and disease-free survival were computed using the Kaplan-Meier technique. The log-rank test was used for survival difference analysis.

RESULTS

(1) The 8th AJCC/UICC N staging exhibited significant stratification for overall survival (OS) and progression-free survival (PFS). JES 11th showed significant OS stratification, but PFS was not well-stratified for N2-N4. (2) Both staging systems demonstrated significant stratification for OS and PFS. (3) AJCC/UICC 8th TNM staging yielded significantly well-stratified OS and PFS in the differing staging group. JES 11th failed to stratify OS and PFS for stages III and IVA. (4) AJCC/UICC 8th TNM stratified OS and PFS significantly well for lower and middle region tumors, whereas JES 11th inadequately stratified stages III and IVA. (5) Significant multivariable analysis results indicated that AJCC/UICC 8th independently predicted poor OS and PFS.

CONCLUSIONS

In Chinese patients with esophageal squamous cell carcinoma who underwent radical (chemo) radiotherapy, the AJCC/UICC 8th edition exhibited superior prognostic prediction capabilities compared with the JES 11th edition.

A novel technique for lymphadenectomy along the left recurrent laryngeal nerve during minimally invasive esophagectomy: a retrospective cohort study

BACKGROUND

In the context of esophageal cancers, lymph nodes located along the left recurrent laryngeal nerve (RLN) exhibit significant involvement, posing significant challenges for lymphadenectomy. The objective of this study is to assess the safety and efficacy of a novel technique for lymphadenectomy called "elastic suspension of left RLN" method, comparing it with the conventional approach.

METHODS

Between January 2016 and June 2020, a total of 393 patients who underwent minimally invasive esophagectomy with gastroplasty and cervical esophagogastric anastomosis were enrolled in the study. Among them, 291 patients underwent the "elastic suspension of left RLN" method, while 102 patients underwent the conventional method. We compared the number of harvested lymph nodes along the left RLN and assessed postoperative complications between these two groups. Additionally, the overall survival (OS) rate was calculated and analyzed for the entire cohort.

RESULTS

In comparison to the conventional group, the elastic suspension group exhibited a higher yield of harvested lymph nodes along the left RLN (5.36 vs 3.07, P < 0.001). Moreover, the incidence of postoperative hoarseness was lower in the elastic suspension group (10.65% vs 18.63%, P = 0.038). The average duration of lymphadenectomy along the left RLN was 11.85 min in the elastic suspension group and 11.51 min in the conventional group, although this difference was not statistically significant (P = 0.091). Notably, the overall 5-year OS was markedly higher in the elastic suspension group compared to the conventional group (64.1% vs. 50.1%, P = 0.020).

CONCLUSIONS

The findings suggest that the novel "elastic suspension of left RLN" method for lymphadenectomy along the left RLN in minimally invasive esophagectomy is both safe and effective. This technique holds promise for widespread adoption in esophagectomy procedures.

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

INTRODUCTION

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.

METHODS

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.

RESULTS

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 5.7 mm, 5.7 mm, 5.5 mm, and 4.8 mm, 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.

CONCLUSION

Region-based criterion for lymph node metastasis of thoracic ESCC is beneficial to improve the diagnostic efficiency of preoperative CT.

The prognostic significance of preoperative nutritional/inflammatory markers and clinicopathological features in resectable esophagectomy patients: possibility of nutritional intervention

BACKGROUND

Preoperative inflammatory or nutritional biomarkers and clinicopathological features may be survival predictors in resectable esophageal squamous cell carcinoma.

METHODS

We included 118 patients with resectable squamous esophageal carcinoma (stages I-IV), assessing preoperative CRP- and albumin-based modified Glasgow prognostic score, the modified controlling nutritional status score, C-reactive protein, neutrophil/lymphocyte ratio, platelet/lymphocyte ratio, pathologic stage, and tumor location(s), looking for correlation with overall survival and relapse-free survival. Using univariate and Cox analysis, we selected the most reliable prognostic factors.

RESULTS

Five-year overall survival and recurrence-free survival were 54.9% and 48.5%, respectively. C-reactive protein values correlated negatively with hypoalbuminemia (P = 0.0036). On univariate analysis, tumor stage, invasion depth, location, nodal involvement, albumin, and modified Glasgow prognostic score were significant prognostic factors for overall and recurrence-free survival. Preoperative C-reactive protein was prognostic factor for overall survival, but not for relapse-free survival (P = 0.017, 0.063, respectively). The Cox proportional hazards model showed the modified Glasgow prognostic score to be an independent prognostic factor for relapse-free survival and overall survival after using the stepwise variable selection procedure. Cox analysis including clinicopathological factors and modified Glasgow prognostic scores showed that only tumor location(s) and pathologic stage were independent prognostic factors for overall survival and recurrence-free survival.

CONCLUSION

Although the modified Glasgow prognostic score is not superior to pathologic stage and tumor location as a biomarker of preoperative nutrition/inflammation and clinicopathological factors, it remains an important prognostic marker in resectable esophageal cancers. Preoperative decreased inflammatory response and improved nutritional status may contribute to prognosis in patients with esophageal cancer.

Machine learning to predict occult metastatic lymph nodes along the recurrent laryngeal nerves in thoracic esophageal squamous cell carcinoma

PURPOSE

Esophageal squamous cell carcinoma (ESCC) metastasizes in an unpredictable fashion to adjacent lymph nodes, including those along the recurrent laryngeal nerves (RLNs). This study is to apply machine learning (ML) for prediction of RLN node metastasis in ESCC.

METHODS

The dataset contained 3352 surgically treated ESCC patients whose RLN lymph nodes were removed and pathologically evaluated. Using their baseline and pathological features, ML models were established to predict RLN node metastasis on each side with or without the node status of the contralateral side. Models were trained to achieve at least 90% negative predictive value (NPV) in fivefold cross-validation. The importance of each feature was measured by the permutation score.

RESULTS

Tumor metastases were found in 17.0% RLN lymph nodes on the right and 10.8% on the left. In both tasks, the performance of each model was comparable, with a mean area under the curve ranging from 0.731 to 0.739 (without contralateral RLN node status) and from 0.744 to 0.748 (with contralateral status). All models showed approximately 90% NPV scores, suggesting proper generalizability. The pathology status of chest paraesophgeal nodes and tumor depth had the highest impacts on the risk of RLN node metastasis in both models.

CONCLUSION

This study demonstrated the feasibility of ML in predicting RLN node metastasis in ESCC. These models may potentially be used intraoperatively to spare RLN node dissection in low-risk patients, thereby minimizing adverse events associated with RLN injuries.

Lymphatic Drainage System and Lymphatic Metastasis of Cancer Cells in the Mouse Esophagus

BACKGROUND

Lymphatic metastasis is commonly seen in patients with esophageal squamous cell carcinoma (ESCC). Both lymphatic metastasis and the number of involved nodes are prognostic for post-operative survival. To better understand lymphatic metastasis of ESCC, there is a need to develop proper animal models.

AIMS

This study is aimed to characterize the morphology and function of the lymphatic drainage system in the mouse esophagus.

METHODS

Immunostaining and fluorescence imaging were used to visualize the lymphatic drainage system in the mouse esophagus. Tracers and cancer cells were orthotopically inoculated into the submucosa of the mouse esophagus to mimic lymphatic metastasis of T1 ESCC.

RESULTS

Using immunostaining of a lymphatic vessel marker (LYVE1), we found that lymphatic vessels were located in the submucosa and muscularis propria of the mouse esophagus, similar to the human esophagus. In the esophagus of ProxTom mice expressing tdTomato in the lymphatic vessels, we discovered a microscopic meshwork of lymphatic vessels. Functionally, orthotopically inoculated tracers (Indian ink and FITC-dextran) were drained from the submucosa into peri-esophageal lymph nodes via lymphatic vessels. Orthotopically inoculated mouse cancer cells (LLC-eGFP, MOC2) metastasized from the submucosa to lymphatic vessels, peri-esophageal lymph nodes, and distant organs (liver and lung) in immunocompetent mice. Similarly, in immunodeficient mice, orthotopically inoculated human ESCC cells (KYSE450-eGFP-Luc) metastasized via the same route.

CONCLUSION

We have characterized the morphology and function of the lymphatic drainage system of the mouse esophagus. These observations lay a foundation for mechanistic and therapeutic studies on lymphatic metastasis of T1 ESCC.

Short-term clinical effects of robot-assisted esophagectomy with thoracic duct resection

Background

Whether extended robot-assisted esophagectomy with thoracic duct resection (RAE-TDR) has a favorable effect on esophageal cancer patients is not yet known. This study sought to analyze the safety and efficiency of RAE-TDR.

Methods

From January 2019 to July 2020, 73 thoracic duct (TD)-resected and 127 TD-preserved consecutive patients who received standard RAE McKeown surgery were enrolled in this study. The perioperative-related indicators of recurrence-free survival (RFS) and overall survival (OS) at 1-year were compared between the 2 groups.

Results

In relation to morbidity, the Clavien-Dindo (CD) classifications for grades greater than or equal to II-III were similar between the 2 groups (P>0.05). The number of retrieved total lymph nodes (LNs) and mediastinal nodes were significantly higher in the TD-resected group than in the TD-preserved group (total lymph nodes: 29.0±11.1 vs. 25.1±8.5, P=0.006; mediastinal nodes: 19.5±8.0 vs. 16.1±5.5, P=0.002). Additionally, more metastatic TD-related LNs were harvested in cT3-4 patients (2.3±3.7 vs. 1.7±2.8; P=0.21). The rates of LN recurrence and local recurrence were similar between the 2 groups (LN recurrence: 6.8% vs. 7.1%, P>0.99; local recurrence: 1.4% vs. 2.4%, P>0.99). The OS and RFS at 1-year were equivalent regardless of the TD procedure at each stage (P>0.05). However, the rate of hematogenous metastasis in the TD-resected group was significantly elevated (17.8% vs. 7.9%; P=0.034).

Conclusions

RAE-TDR may help to improve total and metastatic LN harvest, especially in patients with advanced esophageal squamous cell carcinoma (ESCC) without increasing the intra- and post-operative adverse events. However, RAE-TDR did not lead to a decrease in the local recurrence rate within the short-term follow-up period. Whether the increase in distant metastasis rate in the TD-resected group was associated with relevant immune system damage is unclear. Thus, nonselective RAE-TDR is not routinely recommended.

A comparison of two methods of lymph node dissection along the left recurrent laryngeal nerve in McKeown minimally invasive esophagectomy

Background

Lymph nodes dissection in esophagectomy is an essential procedure for radical resection, which can not only provide more accurate staging but may also improve survival, while it is technically challenging and may lead to recurrent laryngeal nerve (RLN) paralysis. Numerous efforts have been directed to achieve the dissection of more LNs around the RLN and to lower the incidence of RLN palsy, including Bascule method and modified Bascule method. On this basis, we modified and applied a novel method which involves the en bloc dissection of lymph nodes dissection along the left RLN in McKeown minimally invasive esophagectomy (MIE).

Methods

A total of 244 consecutive cases of lymphadenectomy along the left RLN during McKeown MIE at our institution between January 2018 and August 2021 were retrospectively analyzed. The cases were divided into two groups based on the methods of lymphadenectomy along the left RLN: 77 cases received the conventional method (CM group) and 167 cases received the novel method (NM group). The surgical outcomes, especially the impact of surgical proficiency on the outcomes of lymphadenectomy along the left RLN, were assessed and compared between the two groups.

Results

Demographic data of the two cohorts were similar. The number of harvested lymph nodes (LNs) (total/abdomen/left RLN) in the NM group was markedly higher than that in the CM group (32 vs. 27, P=0.006; 11 vs. 9, P=0.038; 3 vs. 2, P=0.044). However, the number of harvested LNs from the chest or right RLN was not significantly different in the two groups. The hoarseness rate was 1.8% in the NM group, which was slightly but not notably lower than that of the CM group (1.8% vs. 2.6%, P=0.681). The incidence of LN metastasis along the left RLN was 13.9%, 15.6%, and 13.2% in the whole cohort, CM group, and NM group, respectively.

Conclusions

Our novel method not only increased the number of LN dissections along left RLN but also slightly reduced the incidence of hoarseness. Therefore, this novel method of lymphadenectomy along the left RLN during McKeown MIE is safe and reliable.

Pattern of relapse following three-field lymphadenectomy of esophageal carcinoma and related factors predictive of recurrence

PURPOSE

For treatment of esophageal carcinoma, the optimal postoperative radiotherapy target volume after three-field lymph node dissection (3-FLD) had not been determined. We analyzed local recurrence pattern of thoracic esophageal carcinoma and risk factors of lymph node recurrence after 3-FLD without prophylactic radiotherapy.

MATERIAL AND METHODS

We reviewed 1282 patients with thoracic esophageal squamous cell carcinoma (ESCC) who were treated with 3-FLD without radiotherapy from 2010 to 2018 and analysed local recurrence patterns and risk factors of lymph node recurrence, in order to provide a reference for determination of the radiotherapy target volume for thoracic ESCC.

RESULTS

The lymph node recurrence accounted for 91.0% of treatment failures. The mediastinal, cervical and abdominal lymph node recurrence accounted for 84.92%, 36.07% and 22.30%, respectively (χ²=264.776, P=0.000). The superior, middle and inferior mediastinal lymph node recurrence rates were 67.54%, 27.87% and 0.98%, respectively (χ²=313.600, P=0.000). Cervical metastases were significantly associated with N stage and Preoperative cervical lymph node status. Abdominal metastases were significantly associated with the number of preoperative abdominal lymph node metastases (LNM), tumor location and N stage.

CONCLUSIONS

The main pattern of local-regional recurrence might be lymph node metastasis after radical 3-FLD without radiotherapy in esophageal carcinoma. The dangerous lymph node recurrence regions included neck, superior and middle mediastinum. The abdominal areas might be irradiated for lower TEC patients with preoperative abdominal LNM.

Comparison of clinicopathological features and prognostic significance between synchronous multiple primary and solitary esophageal squamous cell carcinomas

Background

Synchronous multiple primary esophageal squamous cell carcinoma (S-MPESCC) refers to more than one primary esophageal carcinoma detected in a solitary patient at the time of initial presentation. The purpose of this study was to evaluate the clinicopathological features, appropriate surgical approaches and long-term survival in patients with S-MPESCC by comparing with those with solitary esophageal squamous cell carcinoma (SESCC).

Methods

In total, 567 patients with esophageal squamous cell carcinoma surgically resected in Tianjin Medical University Cancer Institute and Hospital from January 2012 to December 2018 were screened for retrospective analysis (50 in the S-MPESCC group and 516 in the SESCC group).

Results

No significant difference was observed in terms of other characteristics except total alcohol consumption (P = 0.029). S-MPESCC had higher lymph node rate than SESCC (62.0% and 44.1%, respectively; P = 0.015) especially in upper mediastinal (32.0% and 18.6%, respectively; P = 0.023) and abdominal (38.0% and 22.8%, respectively; P = 0.017) regions. The survival was not different between the two groups, and the 5-year survival rates of S-MPESCC and SESCC were 46.2% and 50.8%, respectively (P = 0.507). But for patients with pT3-4 cancers, the survival in S-MPESCC was worse than that in SESCC (P = 0.033). In the multivariate analysis, pT stage of primary cancer was an important independent predictor of prognosis in patients with S-MPESCC (hazard ratio [HR], 3.968; 95% confidence interval [CI], 1.031 to 15.268; P = 0.045).

Conclusions

S-MPESCC was significantly different from SESCC in terms of clinicopathological characteristics include alcohol intake and pattern of lymphatic metastasis. Furthermore, S-MPESCC showed worse long-term survival than SESCC with increasing depth of primary cancer infiltration.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-10283-2.

Approach to Localized Squamous Cell Cancer of the Esophagus

OPINION STATEMENT

Esophageal cancer is a leading cause of cancer deaths worldwide, with an increasing incidence in recent decades. The majority of esophageal cancers are squamous cell carcinoma. The 5-year survival rate of esophageal squamous cell carcinoma (ESCC) is poor, and there remains globally a pressing need for novel treatments that improve patient outcomes and quality of life. In this review, we discuss management of localized ESCC with an update on relevant newly published literature, including targeted therapy and novel biomarkers. The standard treatment approach for locally advanced, resectable ESCC is currently chemoradiation with or without surgery. Here we discuss different approaches to endoscopic resection, surgery, and radiation therapy. Although the typical chemotherapy regimen is a combination of a platinum with a fluoropyrimidine or paclitaxel, different regimens are being evaluated. With the landscape of immunotherapy rapidly evolving, at the forefront of new treatments for ESCC is immunotherapy and other targeted agents. Ultimately, the treatment approach should be individualized to each patient.

Preoperative Clinical Characteristics Predict Recurrent Laryngeal Nerve Lymph Node Metastasis and Overall Survival in Esophageal Squamous Cell Carcinoma: A Retrospective Study With External Validation

Background

Recurrent laryngeal nerve (RLN) lymph node metastasis (LNM) is not rare in patients with esophageal squamous cell carcinoma (ESCC). We aimed to develop and externally validate a preoperative nomogram using clinical characteristics to predict RLN LNM in patients with ESCC and evaluate its prognostic value.

Methods

A total of 430 patients with ESCC who underwent esophagectomy with lymphadenectomy of RLN LNs at two centers between May 2015 and June 2019 were reviewed and divided into training (center 1, n = 283) and external validation cohorts (center 2, n = 147). Independent risk factors for RLN LNM were determined by multivariate logistic regression, and a nomogram was developed. The performance of the nomogram was assessed in terms of discrimination, calibration, clinical usefulness, and prognostic value. The nomogram was internally validated by the bootstrap method and externally validated by the external validation cohort.

Results

Multivariate analysis indicated that clinical T stage (P <0.001), endoscopic tumor length (P = 0.003), bioptic tumor differentiation (P = 0.004), and preoperative carcinoembryonic antigen level (P = 0.001) were significantly associated with RLN LNM. The nomogram had good discrimination with the area under the curve of 0.770 and 0.832 after internal and external validations. The calibration curves and decision curve analysis confirmed the good calibration and clinical usefulness of this model. High-risk of RLN LNM predicted by the nomogram was associated with worse overall survival in the external validation cohort (P <0.001).

Conclusion

A nomogram developed by preoperative clinical characteristics demonstrated a good performance to predict RLN LNM and prognosis for patients with ESCC.

C-X-C motif chemokine ligand 12 (CXCL12)/C-X-C motif chemokine receptor 7(CXCR7) regulates epithelial-mesenchymal transition process and promotes the metastasis of esophageal cancer by activating signal transducer and activator of transcription 3 (STAT3) pathway

Esophageal cancer is a malignant tumor of the digestive system that is prone to metastasis. Chemokines and their receptors act an essential role in the occurrence and development of tumors. Here, we investigated the regulatory mechanism of CXCL12/CXCR7 in the growth and metastasis of esophageal cancer. CXCR7 was found highly expressed in clinical tissues and cells of esophageal cancer. Knockdown of CXCR7 inhibited the proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) process of esophageal cancer cells. The knockdown of chemokine CXCL12 also inhibited the expression of EMT-related proteins and the mesenchymal morphology changes of esophageal cancer cells, but the knockdown of C-X-C motif chemokine receptor 4 (CXCR4) had no such effect. Furthermore, the knockdown of CXCR7 attenuated the enhanced EMT process induced by CXCL12 overexpression, while the knockdown of CXCR4 cannot inhibit this process. In addition, overexpressed CXCL12/CXCR7 activated the downstream STAT3 pathway, but had little effect on the extracellular regulated protein kinase (ERK) or serine-threonine kinase (AKT) pathways. Inhibition of the STAT3 pathway using AZD9150 weakened the accelerated effects of CXCL12/CXCR7 on the growth and metastasis of esophageal cancer in vitro and in vivo. In conclusion, our research revealed that CXCL12/CXCR7 regulates EMT and other malignant processes by activating the STAT3 pathway to accelerate the growth and metastasis of esophageal cancer.

Lymph node metastasis pattern and significance of left gastric artery lymph node dissection in esophagectomy for esophageal cancers

Purpose

To investigate the lymph node metastasis pattern and significance of dissection of the left gastric artery lymph nodes in radical en bloc esophagectomy for esophageal squamous carcinomas based on the lymphatic drainage pathway revealed by carbon nanoparticle labeling.

Materials and methods

Patients who underwent en bloc esophagectomy endoscopically were retrospectively enrolled. Carbon nanoparticles were injected in the submucosa of upper thoracic esophagus to label the relevant draining lymph nodes. The clinical data, lymph nodes dissected, surgical technique, and complications were analyzed.

Results

En bloc esophagectomy was successful in all 179 patients. Metastases to the left gastric artery lymph nodes were positive in 42 patients (23.5%) but negative in 137 (76.5%). The left gastric lymph nodes were labeled, whereas no celiac lymph nodes were labeled by carbon nanoparticles. A total of 4652 lymph nodes were resected, with 26 lymph nodes per patient. Seventy-three patients had lymph node metastasis (73/179). Seventeen patients had metastasis to the recurrent laryngeal nerve lymph nodes (9.5%). The metastasis rate of the lower thoracic esophageal cancer to the left gastric artery lymph nodes was 37.0%, significantly greater than that at the middle (15.4%) or upper (6.7%) thoracic segment. The lymph node metastasis rate was significantly (P < 0.05) increased with the length of the cancerous lesion, infiltration depth, and poor differentiation. Univariate analysis revealed that the metastasis rate to the left gastric artery lymph nodes was significantly (P < 0.05) associated with paraesophageal lymph node metastasis, para-cardial lymph metastasis, and TNM classification. Multivariate analysis indicated that cancer location (odds ratio 8.32, 95% confidence interval 2.12–32.24) was significantly (P < 0.05) associated with metastasis to the left gastric artery lymph nodes, with the cancer at the middle and lower thoracic segments significantly more than in the upper thoracic segment.

Conclusion

Certain patterns exist in lymph node metastasis of esophageal cancer, and in radical esophagectomy of esophageal cancers, dissection of the left gastric artery lymph nodes is necessary to prevent possible residual or metastasis of esophageal squamous carcinomas based on the lymphatic drainage pathway of esophageal carcinomas demonstrated by carbon nanoparticle labeling.

Role of Recurrent Laryngeal Nerve Lymph Node Dissection in Surgery of Early-Stage Esophageal Squamous Cell Carcinoma

BACKGROUND

In esophageal cancer surgery, it is difficult to perform thorough dissection of lymph nodes along the recurrent laryngeal nerve (RLN-LN). However, there are limited data regarding the necessity of RLN-LN dissection in surgery for superficial esophageal squamous carcinoma (focused on T1b tumor) and its role in locoregional control and accurate nodal staging.

METHODS

Between 2001 and 2016, 567 patients with pT1N0 and 927 patients with cT1N0 squamous cell carcinoma were identified in a prospectively maintained, single institution esophagectomy registry. Sufficient or insufficient RLN-LN assessment group was defined by receiver operating characteristic curve analysis of the number of RLN-LN harvested. To mitigate bias, inverse probability weighting adjustment and several sensitivity analyses were performed.

RESULTS

In the pT1N0 cohort, patients with sufficient (≥ 4) harvested RLN-LNs showed significantly superior 5-year recurrence-free survival (89.1% versus 74.8%, log-rank P < 0.001). Patients with insufficient RLN-LN dissection mainly developed locoregional failure at the upper mediastinal or cervical area (87% of total recurred cases). The survival impact of sufficient RLN-LN dissection was more prominent in subsets of upper-middle thoracic tumors or with deep submucosal invasion. In the analysis on cT1N0 cohort, sufficient RLN-LN assessment conferred a 1.5-fold increase in the discovery of positive-nodal disease (19.4% versus 27.8%, P = 0.008).

CONCLUSIONS

Adequate RLN-LN dissection during surgery may help reduce the risk of recurrence and enhance the accuracy of nodal staging in early-stage esophageal squamous cell carcinoma. Therefore, meticulous surgical evaluation for this region should not be underrated, particularly in the high-risk subset with lymph node metastasis. Visual Abstract Graphical summary of key study findings. T wo cohorts (pT1 and cT1 ; both mainly comprised T1b ) were analyzed for separate purposes; the former controlled for pathologic stage was primarily analyzed in terms of survival and recurrence hazard, whereas the latter (controlled for clinical was used for stage migration ( and intention to treat analysis. Th e results show the significance of adequate bilateral RLN LN in the surgery for early stage ESCC (particularly those with T1b)T1b), in terms of accurate nodal staging, effective nodal clearance, and reduced regional.

Overexpression of microRNA-19a-3p promotes lymph node metastasis of esophageal squamous cell carcinoma via the RAC1/CDC42-PAK1 pathway

BACKGROUND

A tendency towards extensive regional lymph node metastasis (LNM) is a typical clinical characteristic of esophageal squamous cell carcinoma (ESCC). Up-regulated microRNA (miR)-19a-3p was verified as a predictor of LNM in ESCC in previous microarray analyses, but the underlying mechanisms remain unclear. Here, in vitro experiments were performed to confirm the effect of miR-19a-3p on promoting LNM and to explore the underlying mechanisms.

METHODS

KYSE-150 and TE-1 cell lines were transfected with lentiviral vectors to inhibit miR-19a-3p (LV-miR-19a-3p-inhibition), and cell proliferation, invasion, and migration were assessed. Target genes of miR-19a-3p were identified by sequencing analysis and quantitative reverse transcription PCR (qRT-PCR); Western blotting was performed to confirm targets and explore the potential mechanisms underlying the effect of miR-19a-3p on LNM.

RESULTS

miR-19a-3p had no effect on ESCC cell proliferation, whereas miR-19a-3p overexpression promoted the invasion and migration of ESCC cells. qRT-PCR verification and western blot analysis showed that LV-miR-19a-3p-inhibition downregulated cell division cycle 42 (CDC42), Rac family small GTPase 1 (RAC1), and p21 activated kinase 1 (PAK1).

CONCLUSIONS

Overexpression of miR-19a-3p increased the invasion and migration of ESCC cells via the RAC1/CDC42-PAK1 pathway, suggesting that this pathway mediates the effect of miR-19a-3p on promoting LNM in ESCC.

Role of chemotherapy after curative esophagectomy in squamous cell carcinoma of the thoracic esophagus: A propensity score-matched analysis

BACKGROUND

The efficacy of postoperative treatment of squamous cell carcinoma of the esophagus has not yet been determined. In this retrospective study, we investigated whether postoperative adjuvant chemotherapy (POCT) confers a survival benefit on patients who undergo curative esophagectomy.

METHODS

A total of 782 patients were enrolled in our study. The patients were divided into surgery alone (S) and surgery plus postoperative chemotherapy (S + POCT) groups. Propensity score matching (PSM) was used to eliminate the differences in baseline characteristics. The primary endpoint was overall survival (OS), which was calculated by the Kaplan-Meier method and compared with the log-rank test. A Cox proportional hazards model was used to identify factors influencing the prognosis.

RESULTS

Of 782 patients, 343 (43.9%) underwent S alone, and 439 (56.1%) underwent S + POCT before PSM. The five-year OS rates were 42.3% and 47.8% in the S and S + POCT groups (p = 0.080), respectively. After PSM (296 patients per group), the five-year OS rates were 48.7% and 56.2% in the S and S + POCT groups (p = 0.025), respectively. For different cycles of POCT, patients with more than three cycles had a better survival than those with less than three cycles. The significant predictive factors for OS were pN stage (HR = 1.861, 95% CI: 1.310-2.645, p = 0.001), number of dissected nodes (HR = 0.621, 95% CI: 0.494-0.781, p < 0.001) and POCT received (HR = 0.699, 95% CI: 0.559-0.875, p = 0.002), which were identified by multivariate Cox regression analyses in the matched samples.

CONCLUSIONS

POCT appears to improve the OS rate of patients with ESCC after resection, and at least four chemotherapy cycles are necessary. These conclusions warrant further confirmation in large-scale multicenter randomized controlled trials.

From McKeown to Ivor Lewis, the learning curve for thoracic lymphadenectomy over the first 100 robotic esophagectomy cases: a retrospective study

Background

Lymphadenectomy is an essential but challenging part of the surgical treatment for esophageal cancer. However, the previously reported learning curve for robotic esophagectomy primarily focused on only one surgical approach (McKeown or Ivor Lewis). However, both approaches must be mastered by a mature robotic surgical team to deal with different clinical conditions and satisfy patients' needs. This study aimed to show how an experienced esophageal surgical team became proficient in both McKeown and Ivor Lewis robotic esophagectomy.

Methods

A retrospective review of the first 100 cases of robot-assisted minimally invasive esophagectomy (RAMIE) by a single surgical team was performed. The cumulative sum (CUSUM) analysis was used to distinguish the change point during the learning course. A subgroup analysis was performed according to a surgical approach (McKeown or Ivor Lewis) to determine the effect of experience from one surgical approach on learning the other RAMIE technique.

Results

According to the tendency of the CUSUM plot, the learning curve was divided into four phases. The subgroup analysis indicated the decline of the CUSUM plot in the 3rd phase originated from the start of the Ivor Lewis approach. The attending surgeon took 23 cases to achieve a significant improvement in the number of harvested thoracic lymph nodes using the McKeown approach. Regardless of the acquired experience of McKeown RAMIE, it took another 18 cases for the surgical team to achieve significant improvement in harvesting thoracic lymph nodes using the Ivor Lewis approach.

Conclusions

Twenty-three cases were needed for an experienced surgical team to improve thoracic lymphadenectomy results using McKeown RAMIE. There was another learning phase during the transition from McKeown to Ivor Lewis esophagectomy. Importantly, the acquired experience from performing McKeown RAMIE could shorten how long it takes to learn Ivor Lewis RAMIE.

Risk factors for lymph node metastasis in T1 esophageal squamous cell carcinoma: A systematic review and meta-analysis

BACKGROUND

Lymph node metastasis (LNM) affects the application and outcomes of endoscopic resection in T1 esophageal squamous cell carcinoma (ESCC). However, reports of the risk factors for LNM have been controversial.

AIM

To evaluate risk factors for LNM in T1 ESCC.

METHODS

We searched Embase, PubMed and Cochrane Library to select studies related to LNM in patients with T1 ESCC. Included studies were divided into LNM and non-LNM groups. We performed a meta-analysis to examine the relationship between LNM and clinicopathologic features. Odds ratio (OR), mean differences and 95% confidence interval (CI) were assessed using a fixed-effects or random-effects model.

RESULTS

Seventeen studies involving a total of 3775 patients with T1 ESCC met the inclusion criteria. After excluding studies with heterogeneity based on influence analysis, tumor size (OR = 1.93, 95%CI = 1.49-2.50, P < 0.001), tumor location (OR = 1.46, 95%CI = 1.17-1.82, P < 0.001), macroscopic type (OR = 3.17, 95%CI = 2.33-4.31, P < 0.001), T1 substage (OR = 6.28, 95%CI = 4.93-8.00, P < 0.001), differentiation (OR = 2.11, 95%CI = 1.64-2.72, P < 0.001) and lymphovascular invasion (OR = 5.86, 95%CI = 4.60-7.48, P < 0.001) were found to be significantly associated with LNM. Conversely, sex, age and infiltrative growth pattern were not identified as risk factors for LNM.

CONCLUSION

A tumor size > 2 cm, lower location, nonflat macroscopic type, T1b stage, poor differentiation and lymphovascular invasion were associated with LNM in patients with T1 ESCC.

Clinical evaluation of right recurrent laryngeal nerve nodes in thoracic esophageal squamous cell carcinoma

Background

The accuracy of clinical N staging of esophageal squamous cell carcinoma is suboptimal. As an important station of lymph node metastasis, station C201 (right recurrent laryngeal nerve nodes) has rarely been evaluated alone. We aimed to explore an effective way to evaluate the right recurrent laryngeal nerve nodes in thoracic esophageal squamous cell carcinoma.

Methods

We retrospectively analyzed 628 thoracic esophageal squamous cell carcinoma patients who underwent radical resection without neoadjuvant therapy from two Chinese cancer centers. The diameter of the short axis of the largest right recurrent laryngeal nerve node (DC201) was measured on contrast-enhanced multi-slice computed tomography (MSCT). Right recurrent laryngeal nerve nodes were examined by postoperative pathologic results. The receiver operating characteristic (ROC) curve was generated to assess the diagnostic capabilities of DC201 to determine the right recurrent laryngeal nerve nodes status.

Results

ROC curve analysis revealed that the optimal cut-off point of DC201 was 6 mm, with an area under curve (AUC), sensitivity, specificity, and Youden index of 0.896, 71.9%, 88.8%, and 0.607 respectively. When the cut-off point of DC201 was set to 10 mm, sensitivity, specificity and the Youden index were 14.1%, 99.6% and 0.137 respectively. Among 128 patients with right recurrent laryngeal nerve node metastasis, 71 and 108 patients had the largest right recurrent laryngeal nerve node located above the suprasternal notch level and in the tracheoesophageal groove respectively.

Conclusions

When DC201 ≥6.0 mm instead of DC201 ≥10 mm was used to dictate the right recurrent laryngeal nerve nodes metastasis, contrast-enhanced MSCT could evaluate the status of right recurrent laryngeal nerve nodes with high sensitivity and specificity. The largest right recurrent laryngeal nerve nodes were mainly located in the tracheoesophageal groove and/or above the suprasternal notch.

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.

Past, present, and future of three-field lymphadenectomy for thoracic esophageal cancer

In spite of repeated appeal of the effectiveness of three-field lymphadenectomy (3FL) by Japanese esophageal surgeons, it has not been accepted worldwide as a standard therapeutic measure for thoracic esophageal cancer. In this review, a concise summary of the history of 3FL, its present position, and its future perspective is discussed. Although a lack of randomized controlled trial (RCT) is one of the largest criticisms of 3FL, it seems difficult to make 3FL world-standard even if a RCT with a positive result was made. The essence of 3FL has revealed the fact that bilateral cervical paraesophageal nodes and nodes in the bilateral supraclavicular fossae are regional nodes of thoracic esophageal cancer. To let the world admit this essence should be the real endpoint of "3FL issue" without RCT. In the era of new modalities, Japanese surgeons should be free from the idea that 3FL is indispensable though the essence of 3FL should remain.

Transition from video-assisted thoracoscopic to robotic esophagectomy: a single surgeon's experience

Lymph node dissection (LND) along the left recurrent laryngeal nerve (RLN) is a technically challenging part of esophageal cancer surgery, especially after chemoradiotherapy (CRT). Robotic surgery holds promise to increase its safety and feasibility. The aim of this study was to describe a single thoracoscopic surgeon's experience related to the transition from video-assisted esophagectomy (VATE) to robotic esophagectomy (RE)-with a special focus on the safety of left RLN LND. Patients who underwent minimally invasive esophagectomy and RLN dissection following CRT were dichotomized according to the use of robotic surgery (robotic esophagectomy [RE] versus video-assisted thoracoscopic esophagectomy [VATE]). The following parameters were determined: (1) number of dissected nodes, (2) rates of RLN palsy, (3) rates of perioperative complications, and (4) learning curve. Learning curve analysis was performed using the 10-patient moving average (MA) for operation times and with the cumulative sum (CUSUM) method for left RLN LND (target failure rate: 15%). The RE and VATE groups consisted of 39 and 67 patients, respectively. The intraoperative identification of the left RLN was more common in the RE group (97.4%) than in the VATE group (68.7%; P < 0.001). Postoperative left RLN palsy was significantly more frequent in the VATE group (26.9%) than in the RE group (10.3%; P = 0.042), with a higher rate of pneumonia in the former (16.4% versus 2.6%; P = 0.03). The MA chart revealed a downward trend followed by a flattening of the RE operation time at operation number 17 and 29, respectively. CUSUM analysis showed that the left RLN palsy rate decreased to the target rate after 12 operations. We conclude that at least 12 cases are required for a surgeon with prior experience in VATE to safely accomplish left RLN LND through a robotic approach.

Analysis on plausible factors related to the prognosis of stage IV esophageal cancer

To investigate factors related to poor prognosis of patients with stage IV esophageal cancer and to provide some bases on which proper therapeutic schemes could be formulated for stage IV esophageal cancer patients with performance status (PS) score between 0 and 2.Clinical data of 60 patients with stage IV esophageal cancer were retrospectively analyzed, and the relationships of clinical characteristics and therapeutic methods with patients' prognosis were explored. Univariate analysis on factors possibly affecting the prognosis of patients with stage IV esophageal cancer was performed using Log-rank test, and independent risk factors for the prognosis were estimated in multivariate Cox regression analysis through embracing variables which showed statistical significance in univariate analyses.According to univariate analysis results, nutritional status, anemia, therapeutic method, esophageal stent, and visceral metastasis were main influencing factors for the prognosis of stage IV esophageal cancer (P < .05). While in multivariate Cox regression analysis, visceral metastasis was revealed to be an independent risk factor for poor prognosis in patients with stage IV esophageal cancer.Visceral metastasis is an independent risk factor for poor prognosis in patients with stage IV esophageal cancer. Optimizing therapeutic modes according to with or without combined visceral metastasis possesses certain clinical significance in prolonging survival time and in improving the quality of life among patients with stage IV esophageal cancer.

Metastatic incidence of (PET)CT positive lung hilar and retroperitoneal lymph nodes in esophageal cancer patients

BACKGROUND

Extra-regional lymph node metastases strongly determine treatment options in patients with esophageal cancer. Staging modalities such as (FDG-PET) CT scanning frequently show activity in retroperitoneal and lung hilar lymph nodes. This study evaluated the incidence of histologically confirmed metastases, treatment approach and recurrence patterns in patients with (FDG-PET) CT positivity in these regions.

METHODS

All patients with (FDG-PET-) CT positive hilar and/or retroperitoneal lymph nodes at primary staging or restaging discussed at a multidisciplinary tumor board meeting for staging of esophageal cancer between January 2012-December 2017 were included. Biopsies and follow-up were evaluated to determine the presence of metastases and progression rates.

RESULTS

From 2012 to 2017, 65 of 857 patients (7.6%) were selected with positive retroperitoneal and/or hilar lymph nodes. A total of 47/65 (72.3%) patients had positive retroperitoneal lymph nodes, which contained metastases in 19 (29.2%). When no biopsy was performed and curative treatment was given (n = 14), 9 patients had progression or locoregional and distant recurrence. Positive hilar lymph nodes were identified in 21 (32.3%) patients; 4 were biopsied and none contained metastases. In these patients no recurrence of disease was seen during follow-up.

CONCLUSIONS

The majority of biopsied (PET)CT-positive retroperitoneal lymph nodes at staging contained metastases, while biopsied (PET)CT-positive hilar nodes did not. Histological evaluation of (PET)CT -positive retroperitoneal lymph nodes at staging imaging is recommended, while based on this small series, (PET)CT-positive hilar lymph nodes most likely represent reactive lymphadenopathy.

Failure patterns after adjuvant chemoradiotherapy following endoscopic resection for superficial esophageal squamous cell carcinoma

Background

This study evaluated the locations of lymph node recurrence and their association with irradiation fields used for radiotherapy after adjuvant chemoradiotherapy following endoscopic resection for superficial esophageal squamous cell carcinoma.

Methods

Medical records of 96 consecutive patients with superficial esophageal squamous cell carcinoma who underwent adjuvant chemoradiotherapy following endoscopic resection were reviewed. Computed tomography was used to identify whether nodal recurrences were within the elective nodal irradiation field. The cumulative incidence of recurrence was calculated, accounting for death as a competing risk. Univariate and multivariate analyses identified factors predicting nodal recurrence.

Results

The median follow‐up period was 61 months (range: 6‐137 months). Seven patients (7.3%) developed lymph node recurrence only; two patients (2.1%) developed nodal plus local recurrence. Six of the seven cases without local recurrence involved the elective nodal irradiation field, with five cases involving the recurrent nerve lymph nodes. The 5‐year cumulative incidence of lymph node recurrence was higher for T1b tumors with lymphovascular invasion than for T1a tumors with lymphovascular invasion (17.6% vs 6.2%, P = 0.086; HR: 3.74, 95% CI: 0.80‐17.52, P = 0.094) and T1b tumors without lymphovascular invasion (17.6% vs 3.3%, P = 0.031; HR: 6.78, 95% CI: 0.80‐57.63, P = 0.080).

Conclusions

Lymph node recurrence frequently involved the elective nodal irradiation field, with recurrent nerve lymph nodes being common metastasis sites. The high incidence of nodal recurrence for T1b tumors with lymphovascular invasion highlights a need for new strategies for treating this subset of superficial esophageal squamous cell carcinomas.

Lymph node dissection along the recurrent laryngeal nerves in patients with oesophageal cancer who had undergone chemoradiotherapy: is it safe?

OBJECTIVES

Upper mediastinal lymph node dissection (LND)-especially along the recurrent laryngeal nerve (RN)-is the most challenging part of oesophageal cancer surgery. We investigated whether thoracoscopic RN LND may be safely performed in patients with oesophageal cancer who had undergone chemoradiotherapy (CRT).

METHODS

Patients with oesophageal cancer who had undergone thoracoscopic RN LND (n = 103) were divided into 2 groups according to whether they had prior treatment with CRT or not [the CRT group (n = 65) vs the upfront surgery group (n = 38), respectively]. All patients were operated on by a single surgeon. Intergroup comparisons were made in terms of (i) the number of dissected nodes, (ii) rates of RN palsy and (iii) rates of perioperative complications. The learning curve for the RN LND procedure was investigated using the cumulative sum method.

RESULTS

RN LND after CRT was more technically challenging when performed in the left side. Complete skeletonization of the left RN was achieved only in 66.2% of patients in the CRT group (vs 86.8% in the upfront surgery group; P = 0.022). The rate of postoperative left side RN palsy was significantly higher in the CRT group (26.6%) than in the upfront surgery group (7.9%, P = 0.022), albeit resulting in neither higher pneumonia rates nor longer hospital stays. The cumulative sum analysis revealed a steep learning curve for left RN LND in the CRT group. Unfortunately, an acceptable proficiency (left RN palsy rate: 15%) was not achievable even after treatment in 65 cases.

CONCLUSIONS

Thoracoscopic RN LND is safe but poses significant challenges in CRT-treated patients.

Adjuvant therapy for pathological T3N0M0 esophageal squamous cell carcinoma

Background

Tumors invading the depth of adventitia (T3) are the most common pathological type of esophageal squamous cell carcinoma (ESCC). For patients without lymph nodes metastasis, the role of adjuvant therapy is uncertain. This study was intended to retrospectively analyze the survival effects of postoperative adjuvant therapy in such patients.

Methods

A total of 200 patients with pathological T3N0M0 (pT3N0M0) ESCC from January 2012 to September 2014 were enrolled, including a surgery-alone group (Group S) of 111 patients and a surgery followed with adjuvant chemo/radiation/chemoradiation therapy group (Group S + aCRT) of 89 patients.

Results

There was no significant difference in preoperative basic characteristics and postoperative complications between the two groups. Among all patients, 5-year overall survival (OS) rate was 56.6% and the 5-year disease-free survival (DFS) rate was 51.1%, respectively. The 5-year OS rate was 47.2% in Group S, and 68.4% in Group S + aCRT (P=0.004). The 5-year DFS rate was 44.4% in Group S and 59.3% in Group S + aCRT (P=0.036). The 5-year OS and DFS were improved by adjuvant chemoradiotherapy in the subgroups of males, tumor located at the middle of thoracic esophagus, moderate differentiation, number of resected lymph nodes <15. Multivariate analysis showed that adjuvant chemoradiotherapy and female were associated with improved survival.

Conclusions

In our study, the adjuvant therapy was associated with improved survival for patients with pT3N0M0 ESCC.

Genome-wide analysis of long non-coding RNAs in esophageal squamous cell carcinoma reveals their potential role in invasion and metastasis

Background

A high lymphatic metastasis rate and strong local invasive ability are the key characteristics of esophageal squamous cell carcinoma (ESCC) that affect patient survival, and long non‐coding RNAs (lncRNAs) may play a crucial role. We performed genome‐wide analysis of lncRNAs to identify novel biomarkers associated with local invasion and lymphatic metastasis in ESCC.

Methods

Six pairs of ESCC tumor and para‐tumor tissues were subjected to microarray analysis to identify differentially expressed lncRNAs, and 25 pairs of tissues samples were used to verify the effectiveness of screened lncRNAs using quantitative reverse transcription PCR. The correlations between verified lncRNAs and clinicopathological characteristics were analyzed to confirm specific lncRNAs associated with the local invasion and lymphatic metastasis of ESCC, and gene co‐expression analysis was used to predict potential mechanisms.

Results

Microarray analysis identified 1850 lncRNAs with significant differential expression in ESCC. Of 22 lncRNAs selected for quantitative reverse transcription PCR verification, four were significantly upregulated and one was significantly downregulated in ESCC cancer compared to para‐cancer tissues. ENST00000508406.1 was significantly associated with T, N, and tumor node metastasis stages, and NR_037652.1 was significantly associated with N stage. Moreover, 49 lncRNA‐messenger RNA pairs were significantly associated with the two dysregulated lncRNAs and possibly involved in the regulation of local invasion and lymphatic metastasis of ESCC.

Conclusion

The present genome‐wide analysis identified two novel and tumor‐specific lncRNAs for predicting ESCC local invasion and lymphatic metastasis, providing insight into the potential underlying mechanism, which warrants further investigation.

Comparison of short-term outcomes between robot-assisted minimally invasive esophagectomy and video-assisted minimally invasive esophagectomy in treating middle thoracic esophageal cancer

Whether the robot-assisted minimally invasive esophagectomy (RAMIE) has any advantages over the video-assisted minimally invasive esophagectomy (VAMIE) remains controversial. In this study, we tried to compare the short-term outcomes of RAMIE with that of VAMIE in treating middle thoracic esophageal cancer from a single medical center. Consecutive patients undergoing RAMIE or VAMIE for middle thoracic esophageal cancer from April 2016 to April 2017 were prospectively included for analysis. Baseline data and pathological findings as well as short-term outcomes of these two group (RAMIE group and VAMIE group) patients were collected and compared. A total of 84 patients (RAMIE group: 42 patients; VAMIE group: 42 patients) were included for analysis. The baseline characteristics between the two groups were comparable. RAMIE yielded significantly larger numbers of total dissected lymph nodes (21.9 and 17.8, respectively; P = 0.042) and the right recurrent laryngeal nerve (RLN) lymph nodes (2.1 and 1.2, respectively; P = 0.033) as well as abdominal lymph nodes (10.8 and 7.7, respectively; P = 0.041) than VAMIE. Even though RAMIE may consume more overall operation time, it could significantly decrease total blood loss compared to VAMIE (97 and 161 mL, respectively; P = 0.015). Postoperatively, no difference of the risk of major complications or hospital stay was observed between the two groups. In conclusion, RAMIE had significant advantage of lymphadenectomy especially for dissecting RLN lymph nodes over VAMIE with a comparable rate of postoperative complications. Further randomized controlled trials are badly needed to confirm and update our conclusions.

FOXM1: A potential indicator to predict lymphatic metastatic recurrence in stage IIA esophageal squamous cell carcinoma

BACKGROUND

Previous studies have elucidated that FOXM1 may predict poor prognosis in patients with multiple solid malignant tumors. In this study we explored the differential expression of FOXM1 in stage IIA esophageal squamous cell carcinoma (ESCC) and investigated its prognostic value.

METHODS

Immunohistochemistry (IHC) and Western blot were used to detect FOXM1 expression in ESCC. Correlations between FOXM1 expression and clinicopathological variables, and five-year lymphatic metastatic recurrence (LMR) and overall survival (OS) of patients were analyzed.

RESULTS

FOXM1 was aberrantly expressed in ESCC. Statistical analysis revealed a close relationship between FOXM1 expression and tumor size (P = 0.024), depth of invasion (P = 0.048), and degree of differentiation (P = 0.043). The five-year LMR of patients in the FOXM1 overexpression group was significantly increased compared to the low expression group (P = 0.001). The five-year OS of patients in the FOXM1 overexpression group was significantly reduced compared to the low expression group (P = 0.007). Log-rank tests demonstrated that large tumor size (P = 0.044), poor differentiation degree (P = 0.005), deep invasion (P = 0.000), and FOXM1 overexpression (P = 0.007) may indicate poor prognosis in stage IIA ESCC. Cox multivariate regression analysis revealed that all of these variables were independent predictors of unfavorable outcome (P < 0.05).

CONCLUSION

FOXM1 could be a predictor of lymphatic metastatic recurrence in stage IIA ESCC after Ivor Lewis esophagectomy.

Building CT Radiomics Based Nomogram for Preoperative Esophageal Cancer Patients Lymph Node Metastasis Prediction

PURPOSE: To build and validate a radiomics-based nomogram for the prediction of pre-operation lymph node (LN) metastasis in esophageal cancer. PATIENTS AND METHODS: A total of 197 esophageal cancer patients were enrolled in this study, and their LN metastases have been pathologically confirmed. The data were collected from January 2016 to May 2016; patients in the first three months were set in the training cohort, and patients in April 2016 were set in the validation cohort. About 788 radiomics features were extracted from computed tomography (CT) images of the patients. The elastic-net approach was exploited for dimension reduction and selection of the feature space. The multivariable logistic regression analysis was adopted to build the radiomics signature and another predictive nomogram model. The predictive nomogram model was composed of three factors with the radiomics signature, where CT reported the LN number and position risk level. The performance and usefulness of the built model were assessed by the calibration and decision curve analysis. RESULTS: Thirteen radiomics features were selected to build the radiomics signature. The radiomics signature was significantly associated with the LN metastasis (P<0.001). The area under the curve (AUC) of the radiomics signature performance in the training cohort was 0.806 (95% CI: 0.732-0.881), and in the validation cohort it was 0.771 (95% CI: 0.632-0.910). The model showed good discrimination, with a Harrell’s Concordance Index of 0.768 (0.672 to 0.864, 95% CI) in the training cohort and 0.754 (0.603 to 0.895, 95% CI) in the validation cohort. Decision curve analysis showed our model will receive benefit when the threshold probability was larger than 0.15. CONCLUSION: The present study proposed a radiomics-based nomogram involving the radiomics signature, so the CT reported the status of the suspected LN and the dummy variable of the tumor position. It can be potentially applied in the individual preoperative prediction of the LN metastasis status in esophageal cancer patients.

Comparison of two major staging systems of esophageal cancer-toward more practical common scale for tumor staging

The latest 8th edition of TNM Classification of Malignant Tumours by Union for International Cancer Control (UICC) and 11th edition of Japanese Classification of Esophageal Cancer by Japan Esophageal Society (JES) are the two major classifications widely accepted as tools for clinical staging of esophageal cancer. Both systems consist of three main categories, i.e., T, N, and M, but large difference exists between the two. JES system has more detailed sub-classification of T1 tumors reflecting meticulous work by Japanese investigators on superficial esophageal cancer. N-category shows the largest difference. UICC defines the N-category according to only the number of the metastatic regional lymph nodes. The definition of regional nodes in UICC system is static and uniform, and supraclavicular nodes are definitely excluded. In JES system, regional nodes are subgrouped into five different patterns according to the main tumor location, and the supraclavicular nodes are always regional nodes for thoracic esophageal cancer. Japanese surgeons have described the evidence that regional nodes should be dynamically defined according to tumor location and supraclavicular nodes should be included in regional nodes. Compared to the simplified N-category, the staging matrix of UICC system is somewhat complicated. The clinical stage and pathological stage of UICC system are not identical and difference exists also between squamous cell carcinoma (SCC) and adenocarcinoma. It has another system of pathological prognostic grouping. We can imagine several reasons for the difference occurred between the two systems. One is the difference of major pathology. Another reason is the difference of basic concept of cancer treatment. The relative "dependence" on radical surgery in Japan has required the detailed definition of each lymph node station and the evaluation of "efficacy index" of each station. The strict and detailed definition of lymph node stations has been regarded as an obstacle to those who are not familiar with it. Some simplification can be done but maintaining dynamic definition of regional lymph nodes linked to tumor location. If UICC system can accept this concept, I think the two systems can be unified to realize more practical and useful staging system as an international common language.