Analysis of a registry database for esophageal cancer from high-volume centers in China

Surgical quality determines the long-term survival superiority of right over left thoracic esophagectomy for localized esophageal squamous cell carcinoma patients: a real-world multicenter study

OBJECTIVE

The objective was to compare the long-term overall survival (OS) of right versus left thoracic esophagectomy, and to evaluate whether surgical quality impacts comparison result.

BACKGROUND

Controversy regarding the optimal thoracic esophagectomy approach persists for esophageal squamous cell carcinoma (ESCC). No study has assessed the effect of surgical quality in comparison between right and left approaches.

METHODS

The authors consecutively recruited 5556 operable ESCC patients from two high-volume centers in China, of whom 2220 and 3336 received right and left thoracic esophagectomy, respectively. Cumulative sum was used to evaluate the learning curve for operation time of right approach, as the indicator of surgical proficiency.

RESULTS

With a median follow-up of 83.1 months, right approach, harvesting more lymph nodes, tended to have a better OS than left approach (Mean: 23.8 vs. 16.7 nodes; adjusted hazard ratio (HR)=0.93, 95% CI: 0.85-1.02). Subset analysis by the extent of lymphadenectomy demonstrated that right approach with adequate lymphadenectomy (≥15 nodes) resulted in statistically significant OS benefit compared with left approach (adjusted HR=0.86, 95% CI: 0.77-0.95), but not with limited lymphadenectomy. Subset analysis by surgical proficiency showed that proficient right approach conferred a better OS than left approach (adjusted HR=0.75, 95% CI: 0.64-0.88), but improficient right approach did not have such survival advantage.

CONCLUSIONS

Surgical quality plays a crucial role in survival comparison between surgical procedures. Right thoracic esophagectomy performed with adequate lymphadenectomy and surgical proficiency, conferring more favorable survival than left approach, should be recommended as the preferred surgical procedure for localized ESCC.

Esophageal cancer cell-derived small extracellular vesicles decrease circulating Tfh/Tfr via sEV-PDL1 to promote immunosuppression

Esophageal cancer (EC) is a deadly malignancy. Small extracellular vesicles (sEVs) with programmed death ligand 1 (sEV-PDL1) induce immune escape to promote tumor progression. Furthermore, the imbalance between circulating follicular helper T (Tfh) and circulating follicular regulatory T (Tfr) cells is related to the progression of many malignant tumors. However, the role of the EC-derived sEV-PDL1 in circulating Tfh/Tfr is unknown. Circulating Tfh and Tfr cells were detected by flow cytometry. sEVs were isolated through differential centrifugation and cultured for cell expansion assays. Naïve CD4+ T cells were isolated, stimulated, and cultured with sEVs to evaluate the frequencies, phenotypes, and functions of Tfh and Tfr cells. The proportion of circulating Tfh in patients with EC was lower than that in healthy donors (HDs), whereas that of circulating Tfr was higher. The EC group showed significantly lower circulating Tfh/Tfr and a higher level of sEV-PDL1 than HDs. Notably, sEV-PDL1 was negatively correlated with circulating Tfh/Tfr in the EC group. In vitro assays, sEV-PDL1 inhibited Tfh expansion, enhanced the cytotoxic T lymphocyte-associated antigen 4+ (CTLA4+) Tfh cell percentage, decreased the levels of interleukin (IL)-21 and interferon-γ, and increased IL-10. sEV-PDL1 promoted the expansion and immunosuppressive functions of circulating Tfr; the increased percentages of CTLA4+ Tfr and inducible T cell co-stimulator+ Tfr were accompanied with high IL-10. However, applying an anti-PDL1 antibody significantly reversed this. Our results suggest a novel mechanism of sEV-PDL1-mediated immunosuppression in EC. Inhibiting sEV-PDL1 to restore circulating Tfh/Tfr balance provides a novel therapeutic approach for EC.

Prognostic value and immune landscapes of cuproptosis-related lncRNAs in esophageal squamous cell carcinoma

BACKGROUND

Precisely forecasting the prognosis of esophageal squamous cell carcinoma (ESCC) patients is a formidable challenge. Cuproptosis has been implicated in ESCC pathogenesis; however, the prognostic value of cuproptosis-associated long noncoding RNAs (CuRLs) in ESCC is unclear.

METHODS

Transcriptomic and clinical data related to ESCC were sourced from The Cancer Genome Atlas (TCGA). Using coexpression and Cox regression analysis to identify prognostically significant CuRLs, a prognostic signature was created. Nomogram models were established by incorporating the risk score and clinical characteristics. Tumor Immune Dysfunction and Rejection (TIDE) scores were derived by conducting an immune landscape analysis and evaluating the tumor mutational burden (TMB). Drug sensitivity analysis was performed to explore the underlying molecular mechanisms and guide clinical dosing.

RESULTS

Our risk score based on 5 CuRLs accurately predicted poorer prognosis in high-risk ESCC patients across almost all subgroups. The nomogram that included the risk score provided more precise prognostic predictions. Immune pathways, such as the B-cell receptor signaling pathway, were enriched in the datasets from high-risk patients. High TMB in high-risk patients indicated a relatively poor prognosis. High-risk patients with lower TIDE scores were found to benefit more from immunotherapy. High-risk patients exhibited greater responsiveness to Nilotinib, BI-2536, P22077, Zoledronate, and Fulvestrant, as revealed by drug sensitivity analysis. Real-time PCR validation demonstrated significant differential expression of four CuRLs between ESCC and normal cell lines.

CONCLUSIONS

The above risk score and nomogram can accurately predict prognosis in ESCC patients and provide guidance for chemotherapy and immunotherapy.

Postoperative serum squamous cell carcinoma antigen and carcinoembryonic antigen predict overall survival in surgical patients with esophageal squamous cell carcinoma

Background

Tumor markers are routinely used in clinical practice. However, for resectable patients with esophageal squamous cell carcinoma (ESCC), they are applied infrequently as their prognostic significance is incompletely understood.

Methods

This historical cohort study included 2769 patients with resected ESCC from 2011 to 2018 in a high-risk area in northern China. Their clinical data were extracted from the Electronic Medical Record. Survival analysis of eight common tumor markers was performed with multivariable Cox proportional hazards regressions.

Results

With a median follow-up of 39.5 months, 901 deaths occurred. Among the eight target markers, elevated postoperative serum SCC (Squamous cell carcinoma antigen) and CEA (Carcinoembryonic antigen) predicted poor overall survival (SCC HRadjusted: 2.67, 95% CI: 1.70-4.17; CEA HRadjusted: 2.36, 95% CI: 1.14-4.86). In contrast, preoperative levels were not significantly associated with survival. Stratified analysis also demonstrated poorer survival in seropositive groups of postoperative SCC and CEA within each TNM stage. The above associations were generally robust using different quantiles of concentrations above the upper limit of the clinical normal range as alternative cutoffs. Regarding temporal trends of serum levels, SCC and CEA were similar. Their concentrations fell rapidly after surgery and thereafter remained relatively stable.

Conclusion

Postoperative serum SCC and CEA levels predict the overall survival of ESCC surgical patients. More importance should be attached to the use of these markers in clinical applications.

Minimally Invasive or Open Esophagectomy for Treatment of Resectable Esophageal Squamous Cell Carcinoma? Answer From a Real-world Multicenter Study

OBJECTIVE

To evaluate the long-term and short-term outcomes of MIE compared with OE in localized ESCC patients in real-world settings.

BACKGROUND

MIE is an alternative to OE, despite the limited evidence regarding its effect on long-term survival.

METHODS

We recruited 5822 consecutive patients with resectable ESCC in 2 typical high-volume centers in southern and northern China, 1453 of whom underwent MIE. Propensity score-based overlap weighted regression adjusted for multifaceted confounding factors was used to compare outcomes in the MIE and OE groups.

RESULTS

Five-year OS was 62.7% in the MIE group and 57.7% in the OE group. The overlap weighted Cox regression showed slightly better OS in the MIE group (hazard ratio 0.93, 95% confidence interval: 0.82-1.06). Although duration of surgery was longer and treatment cost higher in the MIE group than in the OE group, the number of lymph nodes harvested was larger, the proportion of intraoperative blood transfusions lower, and postoperative complications less in the MIE group. 30-day (risk ratio [RR] 0.77, 0.381.55) and 90-day (RR 0.79, 0.46-1.35) mortality were lower in the MIE group versus the OE group, although not statistically significant. These findings were consistent across different analytic approaches and subgroups, notably in the subset of ESCC patients with large tumors.

CONCLUSIONS

MIE can be performed safely with OS comparable to OE for patients with localized ESCC, indicating MIE may be recommended as the primary surgical approach for resectable ESCC in health facilities with requisite technical capacity.

Symptom Experiences before Medical Help-Seeking and Psychosocial Responses of Patients with Esophageal Cancer: A Qualitative Study

Objective. The purpose of this study was to investigate patients with esophageal cancer symptom experiences before seeking medical help and psychosocial responses. Methods. Within one month of diagnosis, semistructured interviews were held with 14 adult patients with esophageal cancer. To fully comprehend the symptom experiences that patients with esophageal cancer had prior to seeking medical help and the psychosocial responses they had to these experiences, thematic analysis and interpretative phenomenological analysis were used. Results. Patients with esophageal cancer recounted their symptom experiences, and psychosocial responses were categorized into three main themes: physical, psychological, and social. Three subthemes were included in the physiological aspect: early symptoms (warning signs), specific symptoms (the catalyst for seeking medical help), and concurrent symptoms (masked side effects). Four subthemes were associated with psychological aspects: unfairness, regret, worry, and acceptance. Two subthemes were related to the social element, namely, dragging down one’s family and societal self-isolation. Conclusion. Due to the self-remitting nature of early symptoms, the normalization of their interpretation, and concealment by other illnesses, patients with esophageal cancer may delay medical help-seeking. The findings could serve as a reference for healthcare professionals to implement tailored psychosocial interventions and help patients identify symptoms early in order to seek medical help.

Is Adjuvant Therapy a Better Option for Esophageal Squamous Cell Carcinoma Patients Treated With Esophagectomy? A Prognosis Prediction Model Based on Multicenter Real-World Data

OBJECTIVE

To construct a prediction model for more precise evaluation of prognosis which will allow personalized treatment recommendations for adjuvant therapy in patients following resection of ESCC.

BACKGROUND

Marked heterogeneity of patient prognosis and limited evidence regarding survival benefit of various adjuvant therapy regimens pose challenges in the clinical treatment of ESCC.

METHODS

Based on comprehensive clinical data obtained from 4129 consecutive patients with resected ESCC in a high-risk region in China, we identified predictors for overall survival through a 2-phase selection based on Cox proportional hazard regression and minimization of Akaike information criterion. The model was internally validated using bootstrapping and externally validated in 1815 patients from a non-high-risk region in China.

RESULTS

The final model incorporates 9 variables: age, sex, primary site, T stage, N stage, number of lymph nodes harvested, tumor size, adjuvant treatment, and hemoglobin level. A significant interaction was also observed between N stage and adjuvant treatment. N1+ stage patients were likely to benefit from addition of adjuvant therapy as opposed to surgery alone, but adjuvant therapy did not improve overall survival for N0 stage patients. The C -index of the model was 0.729 in the training cohort, 0.723 after bootstrapping, and 0.695 in the external validation cohort. This model outperformed the seventh edition American Joint Committee on Cancer staging system in prognostic prediction and risk stratification.

CONCLUSIONS

The prediction model constructed in this study may facilitate precise prediction of survival and inform decision-making about adjuvant therapy according to N stage.

Effect of extracapsular lymph node involvement on the prognosis of patients with esophageal squamous cell carcinoma

BACKGROUND

According to the eighth edition of the tumor node metastasis (TNM) staging system for esophageal cancer, it is recommended that extracapsular lymph node involvement (EC-LNI) is included as a registered independent variable for the disease. However, its role in the prognosis has not been clearly explained.

OBJECTIVE

To study the value of EC-LNI in the prognosis of esophageal cancer and attempt to explore its molecular mechanism via an enrichment analysis.

METHODS

A retrospective analysis was performed on 544 patients with esophageal squamous cell carcinoma (ESCC) who underwent radical surgery in the department of thoracic surgery of our hospital, focusing on the relationship between EC-LNI and clinicopathological characteristics and its effect on prognosis. Additionally, the mechanism of EC-LNI in esophageal cancer was explored.

RESULTS

Among the 271 patients with lymph node metastasis, 125 were EC-LNI (+). The degrees of tumor differentiation, location, TNM stage, vascular tumor thrombus, and nerve invasion were related to the occurrence of EC-LNI. The stage of TNM was considered an independent risk factor for the development of EC-LNI. A significant difference was found in terms of overall survival (OS) and disease-free survival (DFS) between the EC-LNI (+) and EC-LNI (-) groups. A univariate analysis showed that the degrees of tumor differentiation, T stage, N stage, TNM stage, EC-LNI, EC-LNI number, and EC-LNI distance were significantly correlated with prognosis. A multivariate survival analysis showed that tumor differentiation, TNM stage, and EC-LNI were independent prognostic factors for OS, while TNM stage and EC-LNI were independent prognostic factors for DFS. The enrichment analysis identified the molecular targets and signaling pathways that can regulate cell proliferation, differentiation, and apoptosis.

CONCLUSION

Extracapsular LNI has a high prognostic value in patients with esophageal cancer and is closely related to the stage of tumors. Our preliminary molecular mechanism research indicated that the molecular targets of EC-LNI are expected to become a new direction for the treatment of esophageal cancer.

Effect of Adjuvant Radiation Dose on Survival in Patients with Esophageal Squamous Cell Carcinoma

Background: For patients with esophageal squamous cell carcinoma (ESCC) treated with surgery alone, the incidence of local-regional recurrence remains unfavorable. Postoperative radiotherapy (PORT) has been associated with increased local-regional recurrence-free survival (LRFS), although its application is limited by concerns of PORT-related toxicities. Methods: Among 3591 patients with ESCC analyzed in this study, 2765 patients with T3-4N0 and T1-4N1-3 lesions and specific local-regional status information were analyzed in a subsequent analysis of adjuvant radiation dose (aRTD) effect. Application of the restricted cubic spline regression model revealed a non-linear relationship between aRTD and survival/radiotoxicity. Linear regression analysis (LRA) was performed to evaluate correlations between LRFS and overall survival (OS)/ disease-free survival (DFS). Results: For patients staged T1−2N0, T1−2N1−3, T3−4N0, and T3−4N1−3, 5-year OS in PORT and non-PORT groups were 77.38% vs. 72.91%, p = 0.919, 52.35% vs. 46.60%, p = 0.032, 73.41% vs. 61.19%, p = 0.005 and 38.30% vs. 25.97%, p < 0.001. With aRTD escalation, hazard ratios (HRs) of OS/DFS declined until aRTD exceeded 50Gy, then increased, whereas that of LRFS declined until aRTD exceeded 50 Gy, then remained steady. HR of treatment-related mortality was stable until aRTD exceeded 50 Gy, then increased. LRA revealed strong correlations between LRFS and OS/DFS (r = 0.984 and r = 0.952, respectively). An absolute 1% advancement in LRFS resulted in 0.32% and 0.34% improvements in OS and DFS. Conclusions: An aRTD of 50Gy was well-tolerated, with favorable survival resulting from PORT-related LRFS improvement in patients staged T3−4N0 or T1-4N1−3. Further stratification analyses based on tumor burden would help determine potential PORT-beneficiaries.

Seven Fatty Acid Metabolism-Related Genes as Potential Biomarkers for Predicting the Prognosis and Immunotherapy Responses in Patients with Esophageal Cancer

Background: Esophageal cancer (ESCA) is a major cause of cancer-related mortality worldwide. Altered fatty acid metabolism is a hallmark of cancer. However, studies on the roles of fatty acid metabolism-related genes (FRGs) in ESCA remain limited. Method: We identified differentially expressed FRGs (DE-FRGs). Then, the DE-FRGs prognostic model was constructed and validated using a comprehensive analysis. Moreover, the correlation between the risk model and clinical characteristics was investigated. A nomogram for predicting survival was established and evaluated. Subsequently, the difference in tumor microenvironment (TME) was compared between two risk groups. The sensitivity of key DE-FRGs to chemotherapeutic interventions and their correlation with immune cells were investigated. Finally, DEGs between two risk groups were measured and the prognostic value of key DE-FRGs in ESCA was confirmed in other databases. Results: A prognostic model was constructed based on seven selected DEG-FRGs. TNM staging and CD8+ T cells were significantly correlated with high-risk groups. Low-risk groups exhibited more infiltrated M0 macrophages, an activation of type II interferon (IFN-γ) responses, and were found to be more suitable for immunotherapy. Seven key DE-FRGs with prognostic value were found to be considerably influenced by different chemotherapy drugs. Conclusion: A prognostic model based on seven DE-FRGs may efficiently predict patient prognosis and immunotherapy response, helping to develop individualized treatment strategies in ESCA.

Combined Mean Corpuscular Hemoglobin, Fibrinogen, and Albumin (MF-A) Is a Novel Prognostic Marker in Patients with Resectable Esophageal Squamous Cell Carcinoma

BACKGROUND

The aim was to systematically select blood markers routinely tested in clinical settings, which are independently associated with overall survival (OS) and are able to stratify prognosis of esophageal squamous cell carcinoma (ESCC) patients undergoing esophagectomy.

METHODS

We selected optimal blood markers for prognostic stratification from 60 candidates in a clinical cohort of 1819 consecutive patients with resectable ESCC in China. Selection was carried out using two-step multivariable Cox proportional hazards regression adjusted for multifaceted confounders. A composite index was developed by multiplying risk factors and dividing them by protective factors.

RESULTS

With a median follow-up of 48.07 months, 641 deaths occurred in the 1819 patients and the 5-year OS was 56.30%. Two risk factors (mean corpuscular hemoglobin, fibrinogen) and a protective factor (albumin), all dichotomized and assigned values 1 and 2, were used to construct the composite index marker "MF-A". Three risk groups were created based on the MF-A score including low- (0.5), moderate- (1), and high-risk groups (2 and 4). Compared with patients in the low-risk group (1184/1778, 66.59%), those in the moderate- (488, 27.45%), and high-risk (106, 5.96%) groups were at elevated risk of death (adjusted HR: 1.32, 95% CI: 1.11-1.57; adjusted HR: 2.08, 95% CI: 1.56-2.75; P_trend < 10^-7). Within each TNM stage grouping, OS also trended to be significantly worse as the MF-A score increased.

CONCLUSIONS

"MF-A" is a novel independent predictor which may be used to estimate and stratify prognosis for ESCC patients undergoing esophagectomy.

Deep Learning for Automated Contouring of Gross Tumor Volumes in Esophageal Cancer

Purpose

The aim of this study was to propose and evaluate a novel three-dimensional (3D) V-Net and two-dimensional (2D) U-Net mixed (VUMix-Net) architecture for a fully automatic and accurate gross tumor volume (GTV) in esophageal cancer (EC)–delineated contours.

Methods

We collected the computed tomography (CT) scans of 215 EC patients. 3D V-Net, 2D U-Net, and VUMix-Net were developed and further applied simultaneously to delineate GTVs. The Dice similarity coefficient (DSC) and 95th-percentile Hausdorff distance (95HD) were used as quantitative metrics to evaluate the performance of the three models in ECs from different segments. The CT data of 20 patients were randomly selected as the ground truth (GT) masks, and the corresponding delineation results were generated by artificial intelligence (AI). Score differences between the two groups (GT versus AI) and the evaluation consistency were compared.

Results

In all patients, there was a significant difference in the 2D DSCs from U-Net, V-Net, and VUMix-Net (p=0.01). In addition, VUMix-Net showed achieved better 3D-DSC and 95HD values. There was a significant difference among the 3D-DSC (mean ± STD) and 95HD values for upper-, middle-, and lower-segment EC (p<0.001), and the middle EC values were the best. In middle-segment EC, VUMix-Net achieved the highest 2D-DSC values (p<0.001) and lowest 95HD values (p=0.044).

Conclusion

The new model (VUMix-Net) showed certain advantages in delineating the GTVs of EC. Additionally, it can generate the GTVs of EC that meet clinical requirements and have the same quality as human-generated contours. The system demonstrated the best performance for the ECs of the middle segment.

Neoadjuvant Pembrolizumab and Chemotherapy in Resectable Esophageal Cancer: An Open-Label, Single-Arm Study (PEN-ICE)

Background

In this single-arm study, the efficacy and safety of neoadjuvant pembrolizumab plus chemotherapy were evaluated in patients with resectable esophageal squamous cell carcinoma (ESCC).

Methods

This study included patients with ESCC of clinical stages II–IVA who underwent surgery within 4 to 6 weeks after completing treatment with pembrolizumab (200 mg) combined with a conventional chemotherapy regimen (3 cycles). The safety and efficacy of this combination treatment were evaluated as primary endpoints of the study.

Results

From April 2019 to August 2020, a total of 18 patients (including 14 men) were enrolled, of whom 13 patients progressed to surgery. Postoperative pathology revealed a major pathological response (MPR) in 9 cases (9/13, 69.2%) and a pathological complete response (pCR) in 6 cases (6/13, 46.2%). Five patients (5/18, 27.8%) experienced serious treatment-related adverse events (AEs) of grades 3–4. At the time of data cutoff (Mar 25, 2022), the shortest duration of follow-up was 17.8 months. Programmed death-ligand 1 (PD-L1) expression in pretreatment specimens was not significantly associated with the percentage of residual viable tumor (RVT) (r=−0.55, P=0.08). Changes in counts of CD68⁺ macrophage between pre- and post-treatment specimens were weakly correlated with RVT (r=0.71; P=0.07), while a positive correlation was observed between postoperative forkhead box P3-positive (Foxp3)⁺T cells/CD4⁺Tcells ratios and RVT (r=0.84, P=0.03).

Conclusions

The combination of neoadjuvant immunotherapy and chemotherapy for ESCC is associated with a high pathological response and immunologic effects in the tumor microenvironment (TME). It has acceptable toxicity and great efficacy, suggesting a strong rationale for its further evaluation in randomized clinical trials (RCTs).

Trial Registration

ChiCTR2100048917.

Comprehensive analysis of a new immune-related prognostic signature for esophageal cancer and its correlation with infiltrating immune cells and target genes

Background

The incidence of esophageal cancer (ESCA) is increasing rapidly, and the 5-year survival rate is less than 20%. This study provides new ideas for clinical treatment by establishing a prognostic signature composed of immune-related genes (IRGs), and fully analyzing its relationship with target genes and the tumor microenvironment (TME).

Methods

We downloaded the ESCA expression matrix and clinical information from The Cancer Genome Atlas (TCGA) database. Differential expression genes (DEGs) were identified with the edgeR package and crossed with the IRGs we obtained from the ImmPort database to obtain differential IRGs (DEIRGs). The prognostic signature was then obtained through univariate Cox, LASSO-Cox, and multivariate Cox analyses. The receiver operating characteristic (ROC) curve was used to evaluate the prediction effect of the model. The immune cell infiltration abundance obtained by ssGSEA and therapeutic target genes was used to perform sufficient correlation analysis with the obtained prognostic signature and related genes.

Results

A total of 173 samples were obtained from TCGA database, including 162 tumor and 11 normal samples. The 3,033 differential genes were used to obtain 254 DEIRGs by intersections with 2,483 IRGs (IRGs) obtained from the ImmPort Database. Finally, multivariate Cox regression analysis identified eight prognostic DEIRGs and established a new prognostic signature (HR: 2.49, 95% CI: 1.68–3.67; P<0.001). Based on the expression of the eight genes, the cohort was then divided into high and low risk groups and Kaplan-Meier (K-M) curves were plotted with the log-rank test P<0.0001 and 1-, 3-year area under the curve (AUC) >0.7. The K-M curves grouped according to high and low risks performed well in the two subgroup validation cohorts, with log-rank test P<0.05. There were differences in the degree of infiltration of 16 kinds of immune cells in tumor and normal samples, and the infiltration abundance of 12 kinds of immune cells was different in the high and low-risk groups.

Conclusions

An effective and validated prognostic signature composed of IRGs was established and had a strong correlation with immune cells and target genes of drug therapy.

A multicenter single-arm trial of sintilimab in combination with chemotherapy for neoadjuvant treatment of resectable esophageal cancer (SIN-ICE study)

Background

Preoperative chemotherapy or chemoradiotherapy is the standard treatment for resectable esophageal cancer (EC); however, it is associated with increased postoperative complications and mortality. Recently, Immune Checkpoint inhibitors have been incorporated in the treatment of advanced EC. Its role in the preoperative setting has not been established yet. In this multicenter, single-arm study, we evaluated the efficacy and safety of neoadjuvant therapy with sintilimab in combination with chemotherapy in treating EC.

Methods

Patients received neoadjuvant therapy with 3 cycles of sintilimab 200 mg Q3W in combination with platinum-based chemotherapy. Surgery was performed within 4–6 weeks after neoadjuvant therapy. The primary endpoints of the trial were pathological complete response (pCR) and safety.

Results

A total of 23 patients (21 men and 2 women) were enrolled. Surgery was completed in 17 participants, with 16 achieving R0 resection and 1 had R1 resection, 5 participants refused surgery. One patient progressed prior to surgery. Twenty one patients (91%) had significant improvement in their dysphagia following treatment as assessed by Stooler’s criteria. The majority of patients who underwent resection have a good pathological response and downstaging rate was 76.5% (13/17). A pCR was achieved in 6 cases (6/17, 35.3%) and major pathological response (MPR) in 9 cases (9/17, 52.9%). The main preoperative adverse events (AEs) were vomiting (13/23, 56.5%), leukopenia (12/23, 52.2%), neutropenia (9/23, 39.1%), and malaise (8/23, 34.8%). Immune-related AEs were mild and included hypothyroidism (2/23, 8.7%) and rash (4/23, 17.4%). The incidence of ≥ grade 3 treatment related AEs was 30.4% (7/23). There were no ≥ grade 4 AEs.

Conclusions

Sintilimab in combination with chemotherapy in the neoadjuvant treatment of EC is safe and lead to a high pCR. Therefore, further testing is warranted.

Robot-Assisted Versus Conventional Minimally Invasive Esophagectomy for Resectable Esophageal Squamous Cell Carcinoma: Early Results of a Multicenter Randomized Controlled Trial: the RAMIE Trial

OBJECTIVE

To compare perioperative and long-term outcomes of robot-assisted minimally invasive esophagectomy (RAMIE) and conventional minimally invasive esophagectomy (MIE) in the treatment for patients with esophageal squamous cell carcinoma (ESCC).

SUMMARY BACKGROUND DATA

RAMIE has emerged as an alternative to traditional open or thoracoscopic approaches. Efficacy and safety of RAMIE and MIE in the surgical treatment for ESCC remains uncertain given the lack of high-level clinical evidence.

METHODS

The RAMIE trial was designed as a prospective, multicenter, randomized, controlled clinical trial that compare the efficacy and safety of RAMIE and MIE in the treatment of resectable ESCC. From August 2017 to December 2019, eligible patients were randomly assigned to receive either RAMIE or MIE performed by experienced thoracic surgeons from six high-volume centers in China. Intent-to-treat analysis was performed.

RESULTS

Significantly shorter operation time was taken in RAMIE (203.8 vs. 244.9 mins, P<0.001). Compared to MIE, RAMIE showed improved efficiency of thoracic lymph node dissection in patients who received neoadjuvant therapy (15 vs. 12, P=0.016), as well as higher achievement rate of lymph node dissection along the left recurrent laryngeal nerve (RLN) (79.5% vs. 67.6%, P=0.001). No difference was found in blood loss, conversion rate, and R0 resection. The 90-day mortality was 0.6% in each group. Overall complications were similar in RAMIE (48.6%) compared to MIE (41.8%) (RR, 1.16; 95% CI, 0.92-1.46; P=0.196). Besides, the rate of major complications (Clavien-Dindo classification ≥ III) was also comparable (12.2% vs. 10.2%, P=0.551). RAMIE showed similar incidences of pulmonary complications (13.8% vs. 14.7%; P=0.812), anastomotic leakage (12.2% vs. 11.3%; P=0.801) and vocal cord paralysis (32.6% vs. 27.1%, P=0.258) to MIE.

CONCLUSIONS

Early results demonstrate that both RAMIE and MIE are safe and feasible for the treatment of ESCC. RAMIE can achieve shorter operative duration as well as better lymph node dissection in patients who received neoadjuvant therapy. Long-term results are pending for further follow-up investigations.

TRIAL REGISTRATION

ClinicalTrial.gov Identifier: NCT03094351.