Neoadjuvant Sintilimab Plus Chemotherapy in Resectable Locally Advanced Esophageal Squamous Cell Carcinoma

Efficacy and safety of PD-1 Monoclonal antibodies in the treatment of esophageal squamous cell carcinoma: Systematic review and meta Regression

Background

Esophageal Squamous Cell Carcinoma (ESCC) contributes to the global burden of disease. Conventional treatments such as surgical resection and chemotherapy offer limited long-term survival rates. Recently, immunotherapies targeting PD-1 have shown promise in other cancers, but their efficacy in ESCC remains unclear.

Methods

The 31 studies eligible for this study included a total of 10,681 patients who were subjected to immunotherapy, either alone or in combination with traditional chemotherapy. A comprehensive search was conducted on September 1, 2023, across databases including CENTRAL, PubMed, MEDLINE, Web of Science, Embase, and Scopus.

Results

For OSR, results indicate a significantly improved survival at different time points (6, 12, and 24 months), with an odds ratio of 0.636 (95 % CI 0.595-0.680; Z = -13.292; p < 0.00001). In terms of PFS, PD-1 inhibitors demonstrated improvements at different time points; pooled odds ratio was 0.568 (95 % CI 0.511-0.633; Z = -10.357; p < 0.00001). Regarding ORR, the pooled analysis showed an overall odds ratio of 1.724 (95 % CI 1.554-1.913; Z = 10.289; p < 0.00001), indicating improved treatment response. DCR did not suggest a significant advantage for PD-1 inhibitors over chemotherapy, with an odds ratio of 0.904 (95 % CI 0.784-1.043; Z = -1.381; p = 0.167).

Conclusions

There is compelling evidence reinforcing the efficacy and safety of PD-1 inhibitors, as monotherapy or in combination with chemotherapy, for the treatment of ESCC. PD-1 inhibitors demonstrate a significant advantage in terms of OSR, PFS, and ORR.

Prognostic Nutritional Index as a Prognostic Indicator for the Occurrence of Postoperative Complications in Patients with Esophageal Squamous Cell Carcinoma Following Neoadjuvant Immunochemotherapy

Background & Aims

The objective of this study was to evaluate the prognostic nutritional index (PNI) as a predictor of short-term postoperative complications in esophageal squamous cell carcinoma patients undergoing neoadjuvant immunochemotherapy.

Methods

Clinical data were collected from 77 patients undergoing radical esophageal cancer surgery after neoadjuvant immunochemotherapy at Tongji Hospital from January 2022 to January 2023. The receiver operating characteristic curve (ROC) was utilized to establish the optimal cut-off point for the PNI. Subsequently, patients were stratified into low and high PNI groups according to this cut-off point, and comparisons were made between the two groups in terms of clinical data and postoperative complications.

Results

Out of the 77 patients included in the study, 31 were categorized in the low PNI group and 46 in the high PNI group, with a defined cutoff point of 47.38. Significant statistical variances were noted in the occurrence rates of general complications (P < 0.001), pulmonary infections (P < 0.001), and anastomotic fistula (P = 0.034) between the two groups. The low PNI group displayed elevated rates of these complications in comparison to the high PNI group.

Conclusion

The research findings indicate that preoperative nutritional assessment using the PNI can effectively predict short-term postoperative complications in esophageal squamous cell carcinoma patients who have undergone neoadjuvant therapy. Furthermore, the results suggest that implementing nutritional interventions for patients with moderate-to-severe malnutrition, as indicated by preoperative PNI evaluation, may help reduce the incidence of postoperative complications.

Survival outcomes of neoadjuvant immunochemotherapy versus chemotherapy for locally advanced esophageal squamous cell carcinoma

PURPOSE

Neoadjuvant chemotherapy (NCT) is the standard preoperative treatment for resectable locally advanced esophageal squamous cell carcinoma (ESCC). Some studies reported neoadjuvant immunochemotherapy (NICT) could improve pathological response with manageable safety. However, few studies have compared the efficacy and safety of NICT and NCT, especially survival outcomes. In this study, we compared the efficacy and safety of NICT and NCT after a median follow-up of 36.0 months.

METHODS

This was a retrospective study with a 1:1 propensity score matching (PSM). Locally advanced ESCC patients treated with neoadjuvant sintilimab plus chemotherapy or chemotherapy followed by esophagectomy were reviewed. The primary outcome was recurrence-free survival (RFS).

RESULTS

Forty-five patients were identified in each group by PSM. The pathological complete response (pCR) rate in NICT and NCT group were 28.9% and 8.9% (P = 0.02). The hazard ratio (HR) was 0.396 (95% CI 0.171-0.919, p = 0.025) for RFS and 0.377 (95% CI 0.145-0.981, p = 0.038) for overall survival (OS), 3-year RFS was 80.6% and 62.1%, 3-year OS was 86.2% and 68.1%. Patients with pCR, MPR or downstaging had better 3-year RFS and 3-year OS. The incidences of postoperative complications and treatment-related adverse events (TRAEs) were similar.

CONCLUSION

This trial preliminarily shows that NICT improves pathological and survival outcomes over NCT for resectable locally advanced ESCC, with acceptable and manageable safety.

Neoadjuvant chemoimmunotherapy for locally advanced esophageal squamous cell carcinoma: Data from literature review and a real-world analysis

BACKGROUND

Neoadjuvant chemoimmunotherapy (NCIT) for locally advanced esophageal squamous cell carcinoma (ESCC) is supported by increasing data, but the sample size is limited, and the findings are not completely consistent. We conducted a real-world study and a meta-analysis to evaluate the efficacy and safety of NCIT in locally advanced ESCC.

METHODS

We retrospectively assessed the outcomes of patients with locally advanced ESCC who completed NICT and subsequent esophagectomy at our hospital between January 2019 and December 2022, including pathological complete response (pCR) rate, major pathological response (MPR) rate, 1-, 2-, and 3-year overall survival (OS) rates, disease control rate (DCR), objective response rate (ORR), 1-year recurrence rate, R0 resection rate and adverse events. Moreover, a meta-analysis of 27 published literatures was also conducted for comparison.

RESULTS

In the analysis, 128 patients were studied, with 25% achieving pCR, 46.1% MPR, and 99.2% R0 resection. The 1-, 2-, and 3-year OS rates were 91.41% (95% CI: 85.15%-95.63%), 75.00% (95% CI: 66.58%-82.23%) and 64.84% (95% CI: 55.91%-73.07%).ORR and DCR were 31.2% (95% CI: 23.31-39.99) and 64.1% (95% CI: 55.15%-72.38%), and the 1-year recurrence rate was 26.7% (95% CI: 22.5%-38.1%). Treatment-related events occurred in 96.1% but were acceptable. In a meta-analysis of 27 studies with 1734 patients, pooled rates for pCR, MPR, ORR, DCR, and R0 resection were 29%, 52%, 71%, 97%, and 98%, respectively, with a 1-year recurrence rate of 12%.

CONCLUSION

NCIT is safe and provides potential survival benefits for patients with locally advanced ESCC. However, randomized phase 3 trial data is still needed.

Clinical study of camrelizumab combined with docetaxel and carboplatin as a neoadjuvant treatment for locally advanced oesophageal squamous cell carcinoma

Herein, we aimed to evaluate the efficacy and safety of camrelizumab combined with docetaxel and carboplatin as a neoadjuvant treatment for locally advanced oesophageal squamous cell carcinoma (OSCC). Fifty-one patients with OSCC, treated from July 2020 to October 2022, were analyzed. Of them, 41 patients underwent surgery 4-8 weeks after undergoing two cycles of camrelizumab (200 mg IV Q3W) combined with docetaxel (75 mg/m2 IV Q3W) and carboplatin (area under the curve = 5-6 IV Q3W). The primary endpoint was the pathological complete response rate. All 51 patients (100%) experienced treatment-related grades 1-2 adverse events, and 2 patients (3.9%) experienced grade 4 events (including elevated alanine transaminase/aspartate transferase levels and Guillain-Barre syndrome). Fifty patients were evaluated for the treatment efficacy. Of them, 13 achieved complete response, and the objective response rate was 74%. Only 41 patients underwent surgical treatment. The pathological complete response rate was 17.1%, the major pathological response rate was 63.4%, and the R0 resection rate was 100%. Approximately 22% of the patients had tumor regression grades 0. Eight patients (19.5%) developed surgery-related complications. The median follow-up time was 18 months (range: 3-29 months). Four patients experienced disease progression, while four died. The median disease-free survival and overall survival were not reached. Camrelizumab combined with docetaxel and carboplatin is an effective and safe neoadjuvant treatment for locally advanced OSCC. This regimen may afford a potential strategy to treat patients with locally advanced OSCC.

Prognostic implication of UBE2C + CD8 + T cell in neoadjuvant immune checkpoint blockade plus chemotherapy for locally advanced esophageal cancer

BACKGROUND

Immune checkpoint blockers (ICBs) plus chemotherapy as neoadjuvant therapy for patients with esophageal cancer (EC) has gained substantial attention. This study aimed to investigate the early and mid-term outcome of neoadjuvant ICBs plus chemotherapy and discover immune-associated predictors of major pathological response (MPR) for locally advanced EC.

METHOD

Patients with locally advanced EC who received neoadjuvant ICBs plus chemotherapy were retrospectively included between June 2019 to December 2021. Conjoint analysis of Bulk-RNA seq (GSE165252) and scRNA seq (GSE188900) were used to investigate potential prognostic factors and immunological mechanisms, then multiplexed immunofluorescence was applied to validate.

RESULTS

76 patients were included. A total of 21 (27.6 %) patients achieved MPR, with 13 (17.1 %) attaining a pathological complete response. Over a median follow-up of 1.8 years, 6 (7.9 %) patients died and 21 (27.6 %) experienced disease recurrence within 0.6 to 2.1 years after surgery. The overall survival rate and recurrence-free survival rate were 93.3 + 2.9 % and 84.8 + 4.2 % at 12 months, 90.8 + 3.7 % and 67.1 + 6.4 % at 24 months, and 90.8 + 3.7 % and 62.9 + 7.2 % at 36 months, respectively. Patients achieving MPR had a significantly lower risk of recurrence compared to non-responders (9.5 % vs 34.5 %, P = 0.017). Analysis of bulk-RNA seq and scRNA-seq revealed that UBE2C and UBE2C + CD8 + T cells were adverse prognostic factors. Immunohistochemistry demonstrated that the non-MPR group had a higher infiltration of UBE2C + immune cells than MPR group after neoadjuvant treatment. Multiplexed immunofluorescence confirmed that infiltrating UBE2C + CD8 + T cells in MPR group were significantly fewer than non-MPR group after neoadjuvant treatment, indicating their poor prognostic role for EC.

CONCLUSIONS

Neoadjuvant ICBs plus chemotherapy shows promising efficacy in locally advanced EC, with MPR being a significant predictor of lower recurrence risk. Immunological analyses identified UBE2C + CD8 + T cells as adverse prognostic factors, suggesting their potential as biomarkers for patient stratification and treatment response.

Neoadjuvant PD-1 Plus Chemotherapy for Locally Advanced Esophageal Squamous Cell Carcinoma

BACKGROUND

Clinical studies have shown that programmed cell death-1 (PD-1) inhibitors can activate T cells and inhibit cancer growth. Therefore, the use of a PD-1 inhibitor plus chemotherapy as neoadjuvant chemotherapy for locally advanced esophageal cancer is worth further exploration.

METHODS

Patients with locally advanced esophageal squamous cell carcinoma were enrolled in this study to receive two cycles of a preoperative combination of toripalimab, paclitaxel, and cisplatin. Efficacy was evaluated after two treatment cycles. The patients' postoperative pathological staging was analyzed and compared. Surgery was performed within 42 days of the start date of the last chemotherapy cycle.

RESULTS

Neoadjuvant immunochemotherapy achieved a high pathologic complete response (pCR) rate (29.0%), major pathological response rate (41.9%), and objective response rate (80.6%) and demonstrated statistically significant downstaging after neoadjuvant therapy (P < .05) with manageable treatment-related adverse effects. No significant association was found between PD-L1 level and pCR (P = .365). In addition, R0 resection was achieved in all 31 (100%) patients during surgery. For all the included patients, the one-year progression-free survival rate was 87.1% (95% CI: 75.3%-98.9%), the one-year overall survival (OS) rate was 96.8% (95% CI: 79.8%-95.9%), and the two-year OS rate was 83.9% (95% CI: 71.6%-92.2%).

CONCLUSIONS

Our findings indicate that this combination may be a potential neoadjuvant therapy regimen in this setting.

Evaluation of neoadjuvant immunotherapy and traditional neoadjuvant therapy for resectable esophageal cancer: a systematic review and single-arm and network meta-analysis

Objective

This systematic review and meta-analysis aimed to investigate the role of neoadjuvant immunochemotherapy with or without radiotherapy [NIC(R)T] compared to traditional neoadjuvant therapies, without immunotherapy [NC(R)T].

Summary background data

NCRT followed by surgical resection is recommended for patients with early-stage esophageal cancer. However, it is uncertain whether adding immunotherapy to preoperative neoadjuvant therapy would improve patient outcomes when radical surgery is performed following neoadjuvant therapy.

Methods

We searched PubMed, Web of Science, Embase, and Cochrane Central databases, as well as international conference abstracts. Outcomes included R0, pathological complete response (pCR), major pathological response (mPR), overall survival (OS) and disease-free survival (DFS) rates.

Results

We included data from 5,034 patients from 86 studies published between 2019 and 2022. We found no significant differences between NICRT and NCRT in pCR or mPR rates. Both were better than NICT, with NCT showing the lowest response rate. Neoadjuvant immunotherapy has a significant advantage over traditional neoadjuvant therapy in terms of 1-year OS and DFS, with NICT having better outcomes than any of the other three treatments. There were no significant differences among the four neoadjuvant treatments in terms of R0 rates.

Conclusions

Among the four neoadjuvant treatment modalities, NICRT and NCRT had the highest pCR and mPR rates. There were no significant differences in the R0 rates among the four treatments. Adding immunotherapy to neoadjuvant therapy improved 1-year OS and DFS, with NICT having the highest rates compared to the other three modalities.

Systematic Review Registration

https://inplasy.com/inplasy-2022-12-0060/, identifier INPLASY2022120060.

A Novel Predictor of Pathologic Complete Response for Neoadjuvant Immunochemotherapy in Resectable Locally Advanced Esophageal Squamous Cell Carcinoma

Purpose

Neoadjuvant immunochemotherapy (nICT) for resectable locally advanced esophageal squamous cell carcinoma (LA-ESCC) has attracted widespread attention recently, whose safety and clinical benefit was observed in clinical researches. This study aimed to develop and validate a novel predictor systemic inflammation-tumor markers index (SITI) to predict the pathological complete response (pCR) for resectable LA-ESCC patients receiving nICT.

Patients and Methods

A total of 147 LA-ESCC patients who underwent nICT followed by surgery from February 2020 to April 2022 were included in the study. The dynamic change of inflammatory indexes was compared at baseline, after two cycles of nICT and postoperative one month. Least absolute shrinkage and selection operator (LASSO) regression was performed to avoid collinearity and identify key indexes, with SITI constructed. After univariate and multivariate stepwise forward logistic analyses, a nomogram for pCR prediction was developed.

Results

41(27.9%) patients achieved pCR among 147 resectable LA-ESCC patients received nICT. Compared with baseline, most inflammatory indexes were significantly decreased at postoperative one month. 5 key indexes were identified and then a predictive index named SITI was constructed. The result showed that lower SITI and earlier clinical tumor node metastasis (cTNM) stage were more likely to achieve pCR. The nomogram for pCR prediction had excellent discrimination performance (C-index = 0.791).

Conclusion

The SITI is an independent predictor for pCR in resectable LA-ESCC patients received nICT. To our knowledge, our nomogram is the first model using systemic inflammation-tumor markers for pCR prediction and may be a promising predictor to effectively differentiate pCR for nICT in LA-ESCC patients.

Minimally invasive versus open McKeown esophagectomy for patients with esophageal squamous cell carcinoma after neoadjuvant PD-1 inhibitor plus chemotherapy

Introduction

The purpose of this study was to compare short and mid-term outcomes in esophageal squamous cell carcinoma (ESCC) patients undergoing open or minimally invasive McKeown esophagectomy (MIE) after neoadjuvant PD-1 inhibitor plus chemotherapy.

Methods

Patients with locally advanced ESCC underwent open or minimally invasive McKeown esophagectomy after neoadjuvant PD-1 inhibitor plus chemotherapy were retrospectively included from June 2019 to June 2021. The baseline characteristics, pathological data, short-and mid-term outcomes were collected and compared based on the surgical approach.

Results

A total of 35 patients were included in the study. An open procedure was performed for 13 patients (37.1%), and 22 (62.9%) patients underwent MIE after neoadjuvant therapy. Compared with open group, MIE group had shorter operative times (350.8± 117.8 vs. 277.9 ± 30.2 min, P = 0.009). The total number of resected lymph nodes was not significantly different, but more left recurrent laryngeal lymph nodes were harvested from the Open group (2.6 ± 3.2 vs. 0.9 ± 1.7, P = 0.047). The median follow-up time was 1.42 years (range, 0.35-2.59 years) from the first day of treatment. Three patients (8.6%) died during follow-up, one in the open surgery group and two in the MIE group. There were six (17.1%) patients developed recurrence, three in each group. The 2-year cumulative survival rates were 92.3 ± 7.4% and 89.5 ± 7.1% for the open and MIE groups, respectively. Overall survival was not different between the two surgical approaches.

Conclusions

MIE might be safe and feasible for patients with locally advanced ESCC undergoing neoadjuvant PD-1 inhibitor plus chemotherapy.

The survival outcomes of neoadjuvant sintilimab combined with chemotherapy in patients with locally advanced esophageal squamous cell carcinoma

Background

Neoadjuvant programmed death receptor-1 (PD-1) inhibitor combined with chemotherapy has been reported to improve the pathological response of locally advanced esophageal squamous cell carcinoma (ESCC), but the systematic report on survival follow-up is quite few. This study we will report the survival follow-up outcomes after a median follow-up of 21.1 months.

Methods

This was a real-world retrospective study. Locally advanced ESCC patients treated with neoadjuvant sintilimab combined with albumin-bound paclitaxel and nedaplatin followed by surgery and completed at least 1-year follow-up were reviewed. The primary outcome was disease-free survival (DFS) at 24 months. The secondary outcome was overall survival (OS) at 24 months.

Results

Ninety eligible patients were included in the analysis between July 2019 and October 2021. The median number of neoadjuvant cycles was 3 (range 2-4). All patients achieved R0 resection. With a median follow-up of 21.1 months (range 14.0-39.0), the median DFS and median OS had not reached, 2-year DFS rate was 78.3% (95%CI 68.8%-89.1%) and 2-years OS rate was 88.0% (95%CI 80.6%-96.0%). Postoperative pathological stage, pCR, MPR, tumor down-staging were significantly correlated with favorable survival outcome. Univariable and multivariable Cox regression analysis identified cycle number of neoadjuvant treatment as independent predictor of DFS.

Conclusion

Our results preliminarily show a survival benefit of neoadjuvant sintilimab combined with chemotherapy in locally advanced ESCC.

Pre-immunotherapy radiotherapy enhanced the efficacy of multi-line sintilimab in unresectable advanced esophageal squamous cell carcinoma

Background

The use of immunotherapy for the treatment of esophageal squamous cell carcinoma (ESCC) is gradually increasing. In this retrospective study, we evaluated the efficacy and explored potential factors of prognosis in multi-line sintilimab for unresectable advanced ESCC.

Methods

All pathological specimens were available from our Department of Pathology. We performed PD-L1 immunohistochemical staining of surgical or puncture specimens from 133 patients. We evaluated the efficacy of multi-line sintilimab and found potential factors according to multivariate analysis. We assessed the relationship between radiotherapy and immunotherapy, and according to whether patients had received radiotherapy within 3 months prior to immunotherapy, we attempted to analyze differences in progression-free survival (PFS) and overall survival (OS).

Results

A total of 133 patients were enrolled in this retrospective study between January 2019 and December 2021. The median follow-up was 16.1 months. All patients were treated with at least two cycles of sintilimab. Of all patients, a total of 74 experienced disease progression, with a median progression-free survival of 9.0 months (95% CI 7.701-10.299). We found that pre-immunotherapy radiotherapy was a possible predictor that affected the prognosis of multi-line sintilimab and that 3 months was a significant cutoff. A total of 128 patients (96.2%) had received radiotherapy prior to immunotherapy. Of those patients, 89 (66.9%) had received radiation therapy within 3 months prior to immunotherapy. PFS was considerably longer in patients who were treated within 3 months of radiotherapy than in patients who did not receive radiation therapy within 3 months of radiation therapy prior to immunotherapy (median progression-free survival 10.0 months [95% CI 8.030-11.970] vs. 5.0 months [95% CI 2.755-7.245]). Among all patients, the median overall survival was 14.9 months (95% CI 12.558-17.242). Overall survival was significantly longer in patients who had previously received radiotherapy within 3 months prior to immunotherapy than in those who had not (median overall survival 15.3 months [95% CI 13.724-16.876] vs. 12.2 months [10.001-14.399].

Conclusion

Based on this retrospective study, sintilimab is a significant option for patients with unresectable advanced ESCC who have been previously treated, and pre-immunotherapy radiotherapy within 3 months enhanced the efficacy.

Comparison of neoadjuvant immunotherapy versus routine neoadjuvant therapy for patients with locally advanced esophageal cancer: A systematic review and meta-analysis

Background

The neoadjuvant use of immune checkpoint inhibitor combined with chemotherapy (nICT) or chemoradiotherapy (nICRT) in locally advanced esophageal cancer (EC) is currently an area of active ongoing research. Therefore, we carried out a comprehensive meta-analysis to compare the efficacy and safety of the new strategy with routine neoadjuvant strategy, which included neoadjuvant chemotherapy (nCT) and neoadjuvant chemoradiotherapy (nCRT).

Patients and methods

MEDLINE (via PubMed), Embase (via OVID), ISI Web of Science database and Cochrane Library were included. And, all of them were searched for eligible studies between January, 2000 and February, 2023. The pathological complete response (pCR) and major pathological response (MPR) were primary outcome of our study. The second outcome of interest was R0 resection rate. Odds ratio (OR) and associated 95% CI were used as the effect indicators comparing the safety and efficiency of the neoadjuvant immunotherapy with the routine neoadjuvant therapy. Fixed-effect model (Inverse Variance) or random-effect model (Mantel-Haenszel method) was performed depending on the statistically heterogeneity.

Results

There were eight trials with 652 patients were included in our meta-analysis. The estimated pCR rate was higher in the neoadjuvant immunotherapy group (OR =1.86; 95% CI, 1.25-2.75; I² = 32.8%, P=0.166). The different results were found in the esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (EAC) subgroups, the estimated OR was 2.35 (95%CI, 1.00-2.72; I² = 30.9%, P=0.215) in the EAC subgroup, and 2.35 (95% CI, 1.20-4.54; I² = 45.3%, P=0.161) in the ESCC subgroup, respectively. The neoadjuvant immunotherapy also showed the advantage in the MPR rates (OR =2.66; 95% CI, 1.69-4.19; I² = 24.3%, P=0.252). There was no obvious difference between the neoadjuvant immunotherapy and routine neoadjuvant therapy with respect to surgical resection rate, R0 resection rate, surgical delay rate; while more treatment-related adverse events were observed for the neoadjuvant immunotherapy for pneumonitis/pneumonia (OR=3.46, 95% CI, 1.31-9.16; I² = 67.3%, P=0.005) and thyroid dysfunction (OR=4.69, 95% CI, 1.53-14.36; I² = 56.5%, P=0.032).

Conclusion

The pooled correlations indicated that the neoadjuvant immunotherapy (both nICT and nICRT) could significantly increase the rates of pCR and MPR, compared with routine neoadjuvant therapy (both nCT and nCRT) in the treatment of locally advanced EC. The neoadjuvant immunotherapy and routine neoadjuvant therapy were with acceptable toxicity. However, randomized studies with larger groups of patients need to performed to confirm these results.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42020155802.

Advances in the structural characterization of complexes of therapeutic antibodies with PD-1 or PD-L1

Antibody-based immune checkpoint blockade (ICB)-based therapeutics have become effective clinical applications for cancers. Applications of monoclonal antibodies (mAbs) to de-activate the PD-1-PD-L1 pathway could effectively reverse the phenotype of depleted activated thymocytes (T cells) to recover their anti-tumoral activities. High-resolution structures of the complexes of the therapeutic monoclonal antibodies with PD-1 or PD-L1 have revealed the key inter-molecular interactions and provided valuable insights into the fundamental mechanisms by which these antibodies inhibit PD-L1-PD-1 binding. Each anti-PD-1 mAb exhibits a unique blockade mechanism, such as interference with large PD-1-PD-L1 contacting interfaces, steric hindrance by overlapping a small area of this site, or binding to an N-glycosylated site. In contrast, all therapeutic anti-PD-L1 mAbs bind to a similar area of PD-L1. Here, we summarized advances in the structural characterization of the complexes of commercial mAbs that target PD-1 or PD-L1. In particular, we focus on the unique characteristics of those mAb structures, epitopes, and blockade mechanisms. It is well known that the use of antibodies as anti-tumor drugs has increased recently and both PD-1 and PD-L1 have attracted substantial attention as target for antibodies derived from new technologies. By focusing on structural characterization, this review aims to aid the development of novel antibodies targeting PD-1 or PD-L1 in the future.

Comparison of McKeown Minimally Invasive Esophagectomy vs sweet esophagectomy for esophageal squamous cell carcinoma: A retrospective study

There are two most widely used transthoracic esophagectomy methods: the McKeown Minimally Invasive esophagectomy (McKeown MIE) and the Sweet Esophagectomy. We evaluated and compared the therapeutic effects of these two methods to determine the appropriate method for the treatment of middle and lower third esophageal cancer patients who received neoadjuvant chemotherapy combined with immunotherapy (NACI). We retrospectively analyzed 43 sweet esophagectomy cases received NACI and 167 cases with McKeown MIE in the fourth hospital of Hebei Medical University from December 2019 to May 2022. This retrospective observational study showed that Sweet esophagectomy and McKeown MIE after NACI therapy for resectable ESCC patients appeared to be safe with low operative mortality and morbidity rate in the current population. In addition, sweet esophagectomy was associated with a lower incidence of severe complications and shorter hospital stay for patients over 70 years of age compared with McKeown MIE. There were no differences were found in length of stay, mortality and complication incidence rate between the two groups. The Sweet approach has advantage in hospital stay for the treatment of the elderly NACI patients with middle or lower third esophageal squamous cell carcinoma. In conclusion, Sweet esophagectomy and McKeown MIE are both safe, effective, and worthwhile approaches for ESCC patients in immunotherapy age.

Comparison of neoadjuvant immunotherapy plus chemotherapy versus chemotherapy alone for patients with locally advanced esophageal squamous cell carcinoma: A propensity score matching

Objectives

Clinical studies on immune checkpoint inhibitors (ICIs) combined with neoadjuvant chemotherapy (nCT) have been carried out for the resectable esophageal squamous cell carcinoma (ESCC). So far, few studies have compared the survival outcomes of nCT plus ICIs and nCT alone. This study aimed to compare the efficacy and safety of neoadjuvant ICIs combined with nCT versus nCT followed by esophagectomy for patients with resectable locally advanced ESCC.

Methods

A retrospective analysis of ESCC patients underwent nCT or nCT combined with ICIs followed by esophagectomy (from March 2013 to April 2021) was performed. A 1:1 propensity score matching (PSM) with a caliper 0.01 was conducted to balance potential bias.

Results

A total of 47 comparable pairs of ESCC patients receiving nCT and nCT combined with ICIs were selected for the final analysis. The tumor regression grade (TRG) 0 and pathologic complete response (pCR) rates in the nCT+ICIs group were significantly higher than those of the nCT group (21.7% vs. 4.5%, P=0.016; and 17.0% vs. 2.1%, P=0.035, respectively). The rate of nerve invasion was 4.3% in the nCT+ICIs group, significantly lower than 23.4% of the nCT group (P=0.007). The incidences of adverse events in the nCT+ICIs group were similar compared with the nCT group and there was no grade 5 toxicity in either group. The 1-, 2-year disease-free survival rates (DFS) were 95.7%, 80.7% and 76.1%, 63.8% in the two groups (P=0.001, and P=0.046, respectively). The 1-year OS was improved in the nCT+ICIs group, which was close to a statistical difference (95.7% vs. 84.8%, P=0.074). Local recurrence rate in the nCT+ICIs group was 6.4%, significantly lower than 21.3% of the nCT group (P=0.036), while there was no significant difference in the distant metastasis.

Conclusions

Compared with nCT alone, neoadjuvant immunotherapy plus nCT for patients with locally advanced ESCC has an advantage in pathological response, and could improve DFS with a good safety and feasibility, while long term survival validation is still needed further.

Efficacy and safety of neoadjuvant immunotherapy combined with chemotherapy in locally advanced esophageal cancer: A meta-analysis

Objective

The progress of neoadjuvant therapy for resectable locally advanced esophageal cancer has been stagnant. There has been much progress in immunotherapy for advanced esophageal cancer, but the efficacy and safety of neoadjuvant immunotherapy for resectable locally advanced esophageal cancer have not yet been definitively demonstrated.

Methods

Original articles describing the safety and efficacy of neoadjuvant immunotherapy in resectable locally advanced esophagus published until July 2022 were retrieved from PubMed, Embase, and the Cochrane Library. The ratio (OR) and 95% confidence interval (CI) were calculated to conduct heterogeneity and subgroup analysis.

Results

In total, 759 patients from 21 studies were enrolled. The effectiveness of neoadjuvant immunotherapy in combination with chemotherapy was evaluated using the major pathologic response (MPR) and pathologic complete response (PCR). In the enrolled patients, 677 were treated surgically and 664 achieved R0 resection. Major pathological remission was achieved in 52.0% (95% CI: 0.44–0.57) of patients on neoadjuvant immunotherapy combined with chemotherapy and complete pathological remission in 29.5% (95% CI: 0.25–0.32) of patients. The safety was primarily assessed by the incidence of treatment-related adverse events (TRAEs) and surgical resection rates. The incidence of TRAEs and the surgical resection rate combined ORs were 0.15 (95% CI: 0.09–0.22) and 0.86 (95% CI: 0.83–0.89), respectively.

Conclusion

Neoadjuvant immunotherapy combined with chemotherapy in locally advanced resectable esophageal cancer is effective and safe.