Preoperative camrelizumab combined with chemotherapy for borderline resectable ESCC: A single-arm, prospective, phase 2 study

BACKGROUND

We investigated the safety and efficacy of preoperative camrelizumab combined with chemotherapy for treating thoracic borderline resectable esophageal squamous cell carcinoma (Br-ESCC) (ChiCTR2200056728).

METHODS

Patients with thoracic Br-ESCC received intravenous camrelizumab plus chemotherapy and underwent esophagectomy. The primary endpoint was the pathologic complete response (pCR) rate. We introduced computed tomography and endoscopic examination into the diagnostic criteria to increase its reproducibility. Additionally, we defined a new resection status, Rbr+/-, for Br-ESCC.

FINDINGS

Thirty-one patients with Br-ESCC were ultimately enrolled in this study. Overall, 71.0% (22/31) of the patients underwent esophagectomy. R0 resection was achieved in 81.8% of patients (18/22). pCR and major pathological response were observed in 40.9% (9/22) and 63.6% (14/22) of the resected patients, respectively. Eighteen R0 resection patients were redefined according to our Rbr definition; 61.1% (11/18) were classified as Rbr+ resection, and 38.9% (7/18) were classified as Rbr- resection. With a median postoperative follow-up of 17.9 months, 4 patients out of 11 who underwent Rbr+ resection experienced local recurrence (2 of whom achieved pCR). However, no patients (0/7) who underwent Rbr- resection experienced local recurrence.

CONCLUSIONS

Esophagectomy after neoadjuvant immunochemotherapy is a promising radical treatment for Br-ESCC. R0 resection was achieved in 81.8% of patients, and a pCR was observed in 40.9% of resected patients. Even after complete excision, Rbr+ resection leads to a higher rate of local recurrence in patients with Br-ESCC.

FUNDING

This study was supported by the Key Scientific Research Projects of the Institutions of Higher Learning in Henan Province (no. 21A320032).

Residual tumor model in esophageal squamous cell carcinoma after neoadjuvant immunochemotherapy: Frequently involves the mucosa and/or submucosa

Objectives

The efficacy and safety of neoadjuvant immunochemotherapy (nICT) are widely explored in locally advanced esophageal squamous cell carcinoma (ESCC). Whether the "wait-and-see" strategy is applicable in ESCC after nICT is still lacking a theoretical basis. This study aimed to preliminarily explore the distribution of residual tumors and the regression pattern of ESCC after nICT.

Methods

Patients undergoing radical esophagectomy after nICT in Fujian Medical University Union Hospital between January 2020 and March 2022 were identified. The resection specimens were re-evaluated by one experienced pathologist. The pathological response was assessed by tumor regression grade (TRG) (modified Ryan scheme). The TRG grade was divided into grades 0 (pathological complete response), 1, 2, and 3. The pathological stage was evaluated in the Eighth Edition AJCC. In the non-pCR group, the residual model was divided into four types: Type I, regression towards the lumen; type II, regression towards the invasive front; type III, concentric regression; and type IV, scattered regression.

Results

A total of 95 consecutive patients were included for analysis. Seventy-six (80.0%) of 95 patients were in non-pCR (pathological complete response), and nine patients (9/76, 11.84%) had isolated residual tumors in lymph nodes. There was no significant difference in baseline characteristics between the pCR group and the non-pCR group (p > 0.05). The overall distribution of TRG for all esophageal wall layers was TRG 0 = 28 (28/95, 29.5%), TRG 1 = 17 (17/95, 17.9%), TRG 2 = 18 (18.9%, 18/95), and TRG 3 = 32 (32/95, 33.7%). In 67 patients with residual tumors in the esophageal wall (TRG ≧1), 63 (63/67, 94.0%) had residual tumor cells in the mucosa and/or submucosa, and four had isolated residual tumors in the muscle layer (4/67, 6.0%). Further analysis showed eight (8/67, 11.9%) patients with submucosal involvement but without mucosal involvement. The distribution of regression patterns was type I (n = 35, 52.2%), type II (n = 3, 4.5%), type III (n = 8, 11.9%), and type IV (n = 21, 31.3%).

Conclusions

The mucosa and/or submucosa are frequently involved in residual malignancy, and the frequent regression models are regression toward the lumen and random regression. There is an opportunity to carefully test the residual tumors in a subgroup of the population with ESCC following nICT. However, some patients had residual tumors only in the muscle layer or lymph nodes. The clinical application of the wait-and-see strategy in ESCC after nICT should be explored using an appropriate evaluation protocol.

Pathological Responses of the Primary Tumor and Locoregional Lymph Nodes After Neoadjuvant Immunochemotherapy in Esophageal Squamous Cell Cancer

BACKGROUND

The current study attempted to describe the specific patterns of pathological tumor response and locoregional node metastases from surgically resected esophageal squamous cell carcinoma after neoadjuvant immunochemotherapy (NAIC), as well as to explore the association between clinicopathological characteristics and such oncological patterns.

METHODS

Fifty-one patients with cT3 or deeper esophageal squamous cell cancer underwent subtotal esophagectomy after NAIC. The NAIC regimen included intravenous administration of platinum-based and docetaxel- and taxane-based chemotherapeutics along with a 200 mg fixed dose of one programmed death 1 (PD-1) inhibitor, given every 3 weeks. We divided patients into tumor/nodal good-responders and poor-responders based on the pathological observation of the tumor or nodal responses. We also examined the association between clinicopathological factors and tumor/nodal responses. Further, significant baseline predictors for tumor and nodal good-responders were identified using multivariate binary logistic regression.

RESULTS

Of the 51 patients, 68.6% achieved marked primary tumor response. Notably, 21.6% of patients achieved complete pathological response. Significant differences in treatment cycles between tumor good-responders and tumor poor-responders (P = 0.019) were observed. For locoregional nodal responses, only 33.3% of patients achieved down-staged nodal disease. Of the investigated variables, neoadjuvant cycles (odds ratio (OR): 5.271, 95% confidence interval (CI): 1.278 - 21.740, P = 0.022) and pretreatment platelets (OR: 0.979, 95% CI: 0.962 - 0.996, P = 0.017) were identified as independent predictors for good tumor and nodal responses.

CONCLUSIONS

We conclusively noted that most patients receiving NAIC were tumor good-responders, whereas only one-third of patients were nodal good-responders. Furthermore, we identified that treatment cycle number and baseline platelet counts were independent predictors of combined tumor and nodal responses.

Why is endosonography insufficient for residual diagnosis after neoadjuvant therapy for esophageal cancer? Solutions using muscle layer evaluation

BACKGROUND

The diagnosis of residual tumors using endoscopic ultrasound (EUS) after neoadjuvant therapy for esophageal cancer is considered challenging. However, the reasons for this difficulty are not well understood.

AIM

To investigate the ultrasound imaging features of residual tumors and identify the limitations and potential of EUS.

METHODS

This exploratory prospective observational study enrolled 23 esophageal squamous cell carcinoma patients receiving esophagectomy after neoadjuvant therapy [15 patients after neoadjuvant chemotherapy (NAC) and 8 patients after chemoradiotherapy (CRT)] at the Department of Surgery, Chiba University Hospital, between May 2020 and October 2021. We diagnosed the T stage for specimens using ultrasound just after surgery and compared ultrasound images with the cut surface of the fixed specimens of the same level of residual tumor. The ratio of esophageal muscle layer defect measured by ultrasound was compared with clinicopathological factors. Furthermore, the rate of reduction for the muscle layer defect was evaluated using EUS images obtained before and after neoadjuvant therapy.

RESULTS

The accuracy of T stage rate was 61% (n = 14/23), which worsened after CRT (38%, n = 3/8) than after NAC (73%, n = 11/15) because of overstaging. Moreover, pT0 could not be diagnosed in all cases. The detection rate of residual tumor for specimens using ultrasound retrospectively was 75% (n = 15/20). There was no correlation between after-NAC (79%, n = 11/14) and after-CRT (67%, n = 4/6) detection rate. The detection of superficial and submucosal types was poor. The pathologic tumor size and pathological response were correlated. Tumor borders were irregular and echogenicity was mixed type after CRT. There was a correlation between the pT stage (pT0/1 vs pT2/3) and the length of muscle layer circumference (P = 0.025), the length of muscle layer defect (P < 0.001), and the ratio of muscle layer defect (P < 0.001). There was also a correlation between the pT stage and the rate of muscle layer defect reduction measured by EUS (P = 0.001).

CONCLUSION

Compared to pathological images, some tumors are undetectable by ultrasound. Focusing on the esophageal muscle layer might help diagnose the depth of the residual tumor.

The Pattern of Residual Tumor After Neoadjuvant Chemotherapy for Locally Advanced Esophageal Cancer and Its Clinical Significance

OBJECTIVES

To investigate the residual pattern of esophageal cancer in the esophageal wall after neoadjuvant chemotherapy (NAC) and its clinical significance.

BACKGROUND

NAC is a standard treatment for locally advanced esophageal cancer; however, residual tumor patterns in resected specimens after NAC and their clinico-pathological characteristics remain unknown.

METHODS

One hundred twenty consecutive patients with cT3 or deeper esophageal cancer underwent curative esophagectomy after NAC and achieved grade 2 histological responses between 2000 and 2016. Hematoxylin-eosin staining of residual tumor sections revealed 4 remnant categories: Type 1: shallow, Type 2: central, Type 3: deep, and Type 4: diffuse. We examined associations between these Types and clinico-pathological factors, including prognosis.

RESULTS

Forty-five (38%) specimens had no residual tumor cells in the mucosal layer. The adventitia layer displayed the lowest residual tumor cell frequency (18%) among all layers. Types 1, 2, 3, and 4 residual tumor patterns were found in 49 (41%), 33 (28%), 9 (8%), and 29 (24%) patients, respectively. Type 4 showed the maximum standard uptake value after NAC; Types 3 and 4 had higher ratios of venous invasion than Type 1 or 2. Patients with Type 3 or 4 more frequently developed pleural dissemination or distant metastasis than patients with Type 1 or 2. Survival was similar among the 4 Types.

CONCLUSIONS

After NAC for locally advanced esophageal cancer, the shallow residual tumor pattern was most common, but approximately 40% of specimens showed no tumor cells in the mucosal layer. Deep and diffuse remnant patterns were associated with high risks of pleural dissemination and distant metastasis.

Endoscopic evaluation of the esophageal cancer patient after chemoradiotherapy for persistent/recurrent cancer

Endoscopy has an important role in the pre- and post-treatment staging of esophageal cancer. Complete pathologic response following neoadjuvant chemoradiation therapy occurs in approximately 25% of patients. However, the ability to accurately detect this preoperatively with currently available endoscopic modalities is limited such that the default pathway is for fit patients to proceed with surgical resection. This article discusses the available endoscopic modalities (primarily Esophagogastroduodenoscopy [EGD] with mucosal biopsies and endoscopic ultrasonography with or without fine needle aspiration) used for post-treatment staging of esophageal cancer. We present data regarding the benefits and limitations of endoscopic methods in assessing for residual disease. Unfortunately, endoscopic modalities are not accurate enough to identify complete pathological responsers who may avoid surgical resection.

Preoperative prediction of a pathologic complete response of esophageal squamous cell carcinoma to neoadjuvant chemoradiotherapy

BACKGROUND

The accurate prediction of a pathologic complete response (ypT0N0M [LYM] 0 ypStage 0) before operation is essential for selecting appropriate strategies for treating esophageal cancer after neoadjuvant chemoradiotherapy.

METHODS

We reviewed 130 consecutive patients with esophageal squamous cell carcinoma who were evaluated preoperatively using upper gastrointestinal endoscopy, computed tomography, and 18F-fluorodeoxyglucose-positron emission tomography after neoadjuvant chemoradiotherapy and subsequently underwent esophagectomy. Our aim was to determine the diagnostic abilities of computed tomography, 18F-fluorodeoxyglucose-positron emission tomography, and endoscopy to predict preoperatively a pathologic complete response of the primary site of the locally advanced esophageal squamous cell carcinoma and associated lymph nodes to trimodal neoadjuvant chemoradiotherapy. Associations between clinical complete response (ycT0N0M [LYM] 0 ycStage 0) and pathologic complete response were investigated preoperatively.

RESULTS

Twenty-nine (22.3%) and 43 (33.1%) patients, respectively, achieved clinical complete response and pathologic complete response, which were associated (P=.001). The sensitivity and specificity, as well as the positive and negative predictive values of clinical complete response to define pathologic complete response were 39.5%, 86.2%, 58.6%, and 74.3%, respectively. Univariate and multivariate analyses selected clinical complete response as the sole independent preoperative predictor of pathologic complete response (clinical complete responses versus non-clinical complete responses: odds ratio: 0.26, 95% confidence interval, 0.10-0.65, P=.004). Recurrence-free and overall survival (OS) rates were better in patients with than in those without clinical complete response (5-year recurrence-free and overall survival: 69.0% vs 41.4% and 75.9% vs 45.0%, respectively, both P=.02). Furthermore, clinical complete response was an independent preoperative predictor of recurrence-free survival (clinical complete response versus nonclinical complete response: hazard ratio: 2.20, 95% confidence interval, 1.08-4.45, P=.03).

CONCLUSION

Although pathologic complete response was predictable preoperatively to some extent, the accuracy was somewhat low. Considerable caution should be exercised when selecting the watch-and-wait approach with operation as needed and omitting planned operative intervention even for patients who achieve clinical complete response after neoadjuvant chemoradiotherapy.

An analysis of factors affecting the accuracy of endoscopic biopsy after neoadjuvant chemoradiotherapy in patients with esophageal squamous cell carcinoma

PURPOSE

The accuracy of endoscopic esophageal biopsy after neoadjuvant chemoradiotherapy (nCRT) remains suboptimal. We retrospectively examined the factors that may affect the diagnostic accuracy of post-nCRT endoscopic biopsy in patients with esophageal squamous cell carcinoma (ESCC).

MATERIALS AND METHODS

A total of 213 ESCC patients were enrolled. Biopsy findings were cross-checked against the final pathology outcomes (ypT0 versus non-ypT0) to assess their accuracy. The independent predictors of diagnostic accuracy were identified by multivariate logistic regression analysis.

RESULTS

Post-nCRT endoscopic biopsy results were diagnostically consistent with the final pathology outcomes in 116 (54.5%) patients. Multivariate logistic regression analysis identified a long time interval between the completion of nCRT and the endoscopic examination as the only factor independently associated with a higher diagnostic accuracy. Receiver operating characteristic curve analysis showed that the optimal cutoff value for the time interval between nCRT completion and endoscopic biopsy was 45 days. The estimated diagnostic accuracies of biopsies performed before and after the optimal cutoff time were 49.1% and 72.9%, respectively.

CONCLUSIONS

Endoscopic biopsies performed ≥45 days after nCRT are associated with a higher diagnostic accuracy. This time cutoff may serve as a reference to inform the choice of the optimal treatment strategy following nCRT, especially among complete responders in whom surgery withholding is being considered.

Stage-directed individualized therapy in esophageal cancer

Esophageal cancer is the eighth most common cancer worldwide, and the incidence of esophageal carcinoma is rapidly increasing. With the advent of new staging and treatment techniques, esophageal cancer can now be managed through various strategies. A good understanding of the advances and limitations of new staging techniques and how these can guide in individualizing treatment is important to improve outcomes for esophageal cancer patients. This paper outlines the recent progress in staging and treatment of esophageal cancer, with particularly attention to endoscopic techniques for early-stage esophageal cancer, multimodality treatment for locally advanced esophageal cancer, assessment of response to neoadjuvant treatment, and the role of cervical lymph node dissection. Furthermore, advances in robot-assisted surgical techniques and postoperative recovery protocols that may further improve outcomes after esophagectomy are discussed.

Endoscopic biopsy and EUS for the detection of pathologic complete response after neoadjuvant chemoradiotherapy in esophageal cancer: a systematic review and meta-analysis

BACKGROUND AND AIMS

Accurate determination of residual cancer status after neoadjuvant chemoradiotherapy (nCRT) for esophageal cancer could assist in selecting the optimal treatment strategy. The aim of this study was to review the evidence on the diagnostic accuracy of endoscopic biopsy and EUS after nCRT for detecting residual cancer at the primary tumor site (ypT+) and regional lymph nodes (ypN+) as opposed to a pathologic complete response (ypT0 and ypN0).

METHODS

PubMed/Medline, Embase, and the Cochrane library were systematically searched. The analysis included diagnostic studies reporting on the accuracy of endoscopic biopsy or EUS in detecting residual cancer versus complete response after nCRT for esophageal cancer with histopathology as the reference standard. Bivariate random-effects models were used to estimate pooled sensitivities and specificities and examine sources of heterogeneity.

RESULTS

Twenty-three studies comprising 12 endoscopic biopsy studies (1281 patients), 11 EUS studies reporting on ypT status (593 patients), and 10 EUS studies reporting on ypN status (602 patients), were included. Pooled estimates for sensitivity of endoscopic biopsy after nCRT for predicting ypT+ were 34.5% (95% confidence interval [CI], 26.0%-44.1%) and for specificity 91.0% (95% CI, 85.6%-94.5%). Pooled estimates for sensitivity of EUS after nCRT were 96.4% (95% CI, 91.7%-98.5%) and for specificity were 10.9% (95% CI, 3.5%-29.0%) for detecting ypT+, and 62.0% (95% CI, 46.0%-75.7%) and 56.7% (95% CI, 41.8%-70.5%) for detecting ypN+, respectively.

CONCLUSIONS

Endoscopic biopsy after nCRT is a specific but not sensitive method for detecting residual esophageal cancer. Although EUS after nCRT yields a high sensitivity, only a limited number of patients will have negative findings at EUS with still a substantial false-negative rate. Furthermore, EUS provides only moderate accuracy for detecting residual lymph node involvement. Based on these findings, these endoscopic modalities cannot be used to withhold surgical treatment in test-negative patients after nCRT. (

CLINICAL TRIAL REGISTRATION NUMBER

CRD42015016527.).