Impact on Radiological and Pathological Response with Neoadjuvant Chemoradiation and Its Effect on Survival in Squamous Cell Carcinoma of Thoracic Esophagus

Radiomics applications in the modern management of esophageal squamous cell carcinoma

Esophageal cancer ranks among the most lethal malignancies globally, with China accounting for more than half of worldwide esophageal squamous cell carcinoma (ESCC) cases. Late-stage diagnosis frequently precludes surgical intervention, contributing to poor outcomes. While precise clinical assessment is essential for treatment planning, therapeutic responses and prognosis exhibit substantial inter-patient heterogeneity, underscoring the urgent need for reliable biomarkers to enhance prognostic accuracy and guide personalized therapeutic strategies. Radiomics, an emerging field that extracts high-dimensional features from medical images, provides non-invasive approaches to improve diagnostic accuracy, predict survival, monitor adverse events, detect recurrence, and optimize treatment strategies. Radiomics has shown promising potential in the modern management of ESCC. Here, we review the critical contributions of radiomics to ESCC research and clinical practice, examining its workflow, applications, strengths, and limitations. Radiomics represents a compelling frontier with substantial potential to advance precision medicine for ESCC patients.

Osteosarcopenia as a Predictor of Histopathologic Response to Neoadjuvant Chemoradiotherapy in Esophageal Cancer: a Retrospective Cohort Study

PURPOSE

Predicting chemoradiotherapy (CRT) response in esophageal cancer is essential as outcomes vary among patients. This study aimed to evaluate the impact of osteosarcopenia on the effectiveness of neoadjuvant CRT (NACRT).

METHODS

Ninety-five patients with advanced esophageal cancer who underwent surgical resection post-NACRT were included. Sarcopenia and osteopenia were determined using pre-NACRT skeletal muscle index and bone density at L3 and Th11 levels. Patients were categorized based on osteosarcopenia status.

RESULTS

Thirty-seven patients (39%) had osteosarcopenia. Among tumors, 49 (51.6%) were grade 1 (non-responders), 12 (12.6%) were grade 2, and 34 (35.8%) were grade 3 (responders). NACRT was significantly more effective in patients with above-median body mass index, shallow tumor depth, low squamous cell carcinoma antigen levels, and without osteosarcopenia. Osteosarcopenia was independently correlated with the histopathologic response to NACRT. No significant differences in overall or relapse-free survival were observed based on osteosarcopenia status.

CONCLUSION

Osteosarcopenia may predict NACRT response in esophageal cancer.

CT-based delta-radiomics nomogram to predict pathological complete response after neoadjuvant chemoradiotherapy in esophageal squamous cell carcinoma patients

BACKGROUND

This study developed a nomogram model using CT-based delta-radiomics features and clinical factors to predict pathological complete response (pCR) in esophageal squamous cell carcinoma (ESCC) patients receiving neoadjuvant chemoradiotherapy (nCRT).

METHODS

The study retrospectively analyzed 232 ESCC patients who underwent pretreatment and post-treatment CT scans. Patients were divided into training (n = 186) and validation (n = 46) sets through fivefold cross-validation. 837 radiomics features were extracted from regions of interest (ROIs) delineations on CT images before and after nCRT to calculate delta values. The LASSO algorithm selected delta-radiomics features (DRF) based on classification performance. Logistic regression constructed a nomogram incorporating DRFs and clinical factors. Receiver operating characteristic (ROC) and area under the curve (AUC) analyses evaluated nomogram performance for predicting pCR.

RESULTS

No significant differences existed between the training and validation datasets. The 4-feature delta-radiomics signature (DRS) demonstrated good predictive accuracy for pCR, with α-binormal-based and empirical AUCs of 0.871 and 0.869. T-stage (p = 0.001) and differentiation degree (p = 0.018) were independent predictors of pCR. The nomogram combined the DRS and clinical factors improved the classification performance in the training dataset (AUCαbin = 0.933 and AUCemp = 0.941). The validation set showed similar performance with AUCs of 0.958 and 0.962.

CONCLUSIONS

The CT-based delta-radiomics nomogram model with clinical factors provided high predictive accuracy for pCR in ESCC patients after nCRT.

Early regression index (ERI) on MR images as response predictor in esophageal cancer treated with neoadjuvant chemo-radiotherapy: Interim analysis of the prospective ESCAPE trial

PURPOSE

The early regression index (ERI) predicts treatment response in rectal cancer patients. Aim of current study was to prospectively assess tumor response to neoadjuvant chemo-radiotherapy (nCRT) of locally advanced esophageal cancer using ERI, based on MRI.

MATERIAL AND METHODS

From January 2020 to May 2023, 30 patients with esophageal cancer were enrolled in a prospective study (ESCAPE). PET-MRI was performed: i) before nCRT (tpre); ii) at mid-radiotherapy, tmid; iii) after nCRT, 2-6 weeks before surgery (tpost); nCRT delivered 41.4 Gy/23fr with concurrent carboplatin and paclitaxel. For patients that skipped surgery, complete clinical response (cCR) was assessed if patients showed no local relapse after 18 months; patients with pathological complete response (pCR) or with cCR were considered as complete responders (pCR + cCR). GTV volumes were delineated by two observers (Vpre, Vmid, Vpost) on T2w MRI: ERI and other volume regression parameters at tmid and tpost were tested as predictors of pCR + cCR.

RESULTS

Complete data of 25 patients were available at the time of the analysis: 3/25 with complete response at imaging refused surgery and 2/3 were cCR; in total, 10/25 patients showed pCR + cCR (pCR = 8/22). Both ERImid and ERIpost classified pCR + cCR patients, with ERImid showing better performance (AUC:0.78, p = 0.014): A two-variable logistic model combining ERImid and Vpre improved performances (AUC:0.93, p < 0.0001). Inter-observer variability in contouring GTV did not affect the results.

CONCLUSIONS

Despite the limited numbers, interim analysis of ESCAPE study suggests ERI as a potential predictor of complete response after nCRT for esophageal cancer. Further validation on larger populations is warranted.

Potential Predictive Immune and Metabolic Biomarkers of Tumor Microenvironment Regarding Pathological and Clinical Response in Esophageal Cancer After Neoadjuvant Chemoradiotherapy: A Systematic Review

INTRODUCTION

The tumor microenvironment (TME) plays a crucial role in therapy response and modulation of immunologic surveillance. Adjuvant immunotherapy has recently been introduced in post-surgery treatment of locally advanced esophageal cancer (EC) with residual pathological disease after neoadjuvant chemoradiotherapy (nCRT). F-18 fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) remains a valuable imaging tool to assess therapy response and to visualize metabolic TME; however, there is still a paucity in understanding the interaction between the TME and nCRT response. This systematic review investigated the potential of TME biomarkers and 18F-FDG-PET/CT features to predict pathological and clinical response (CR) after nCRT in EC.

METHODS

A literature search of the Medline and Embase electronic databases identified 4190 studies. Studies regarding immune and metabolic TME biomarkers and 18F-FDG-PET/CT features were included for predicting pathological response (PR) and/or CR after nCRT. Separate analyses were performed for 18F-FDG-PET/CT markers and these TME biomarkers.

RESULTS

The final analysis included 21 studies-10 about immune and metabolic markers alone and 11 with additional 18F-FDG-PET/CT features. High CD8 infiltration before and after nCRT, and CD3 and CD4 infiltration after nCRT, generally correlated with better PR. A high expression of tumoral or stromal programmed death-ligand 1 (PD-L1) after nCRT was generally associated with poor PR. Moreover, total lesion glycolysis (TLG) and metabolic tumor volume (MTV) of the primary tumor were potentially predictive for clinical and PR.

CONCLUSION

CD8, CD4, CD3, and PD-L1 are promising immune markers in predicting PR, whereas TLG and MTV are potential 18F-FDG-PET/CT features to predict clinical and PR after nCRT in EC.

The role of 18F-FDG PET/CT in predicting the pathological response to neoadjuvant PD-1 blockade in combination with chemotherapy for resectable esophageal squamous cell carcinoma

PURPOSE

Accurate assessment of residual disease of tumor and lymph nodes after neoadjuvant immunochemotherapy is crucial in the active surveillance for patients with pathological complete response (pCR) and the optimal extent of lymphadenectomy for patients with non-pCR. This post hoc analysis aimed to evaluate the performance of ¹⁸F-FDG PET/CT to predict the pathological response to neoadjuvant immunochemotherapy for esophageal squamous cell carcinoma (ESCC).

METHODS

Fifty-eight resectable ESCC patients received two cycles of camrelizumab in combination with chemotherapy and were enrolled in the final analysis. The ¹⁸F-FDG PET/CT scans were acquired at baseline (scan-1) and after immunochemotherapy but prior to surgery (scan-2). Maximum standardized uptake value (SUV_max), mean standardized uptake value (SUV_mean), tumor-to-blood pool SUV_max ratio (SUV_TBR), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were evaluated for their association with the pathological response to immunochemotherapy.

RESULTS

Nineteen patients (32.8%, 19/58) had pCR and thirty-nine patients (67.2%, 39/58) had non-pCR after two doses of camrelizumab and chemotherapy. At scan-2, the SUV_max, SUV_mean, SUV_TBR, TLG, and MTV were significantly lower in pCR than in non-pCR patients. Decrease in TLG and MTV between scan-2 and scan-1 of the same patient was significantly higher in the pCR than in the non-pCR group. In the receiver operating characteristic curve analysis, SUV_max, SUV_mean, SUV_TBR, TLG, and MTV in scan-2 showed excellent predictive value for the pCR of primary tumors. Furthermore, SUV_max in scan-2 were higher in positive lymph nodes than in negative ones, suggesting a high negative predictive ability (98.6%) with a cut-off value at 1.4.

CONCLUSION

The parameters of ¹⁸F-FDG PET/CT have the excellent performance for predicting pCR after the combined neoadjuvant immunochemotherapy in resectable ESCC.

TRIAL REGISTRATION

ChiCTR2000028900. Registered on January 6, 2020.

Omitting surgery in esophageal cancer patients with complete response after neoadjuvant chemoradiotherapy: a systematic review and meta-analysis

BACKGROUND

Neoadjuvant chemoradiotherapy (nCRT) followed by surgery is a standard treatment modality for locally-advanced esophageal cancer. However, patients who achieve clinical complete response (cCR) after nCRT have been reported to have better prognosis. Further, the role of surgery in these patients is controversial. Thus, this meta-analysis aimed to evaluate whether surgery is still useful in patients with cCR after nCRT.

METHODS

We systematically reviewed the MEDLINE, PubMed, Embase, Cochrane library, and Scopus databases for studies on surgical efficacy in complete responders after concurrent chemoradiotherapy for esophageal cancer. The publication date was set to January 1, 2010-January 31, 2020. The hazard ratio (HR) and risk ratio were used to compare the 2-year overall survival (OS), disease-free survival (DFS), incidence of locoregional failure, distant metastasis, and treatment mortality between the nCRT and nCRT plus surgery groups.

RESULTS

Six articles involving 609 patients were included. There was a significant benefit of nCRT for OS (HR = 0.80, 95% confidence interval [CI] 0.64-0.99, p = 0.04), but not for DFS (HR = 1.55, 95% CI 0.35-6.86, p = 0.56). The nCRT group tended to have lower mortality than the nCRT plus surgery group (risk ratio = 0.15, 95% CI 0.02-1.18, p = 0.07).

CONCLUSION

Omitting surgery provides better OS in complete responders after nCRT. Adding surgery could increase the morbidity and mortality and decrease the quality of life. Thus, nCRT alone could be a feasible approach for patients with cCR.

Role of precision imaging in esophageal cancer

Esophageal cancer is a major cause of morbidity and mortality worldwide. Recent advancements in the management of esophageal cancer have allowed for earlier detection, improved ability to monitor progression, and superior treatment options. These innovations allow treatment teams to formulate more customized management plans and have led to an increase in patient survival rates. For example, in order for the most effective management plan to be constructed, accurate staging must be performed to determine tumor resectability. This article reviews the multimodality imaging approach involved in making a diagnosis, staging, evaluating treatment response and detecting recurrence in esophageal cancer.

Prognostic Value of Lymph Node-To-Primary Tumor Standardized Uptake Value Ratio in Esophageal Squamous Cell Carcinoma Treated with Definitive Chemoradiotherapy

We aimed to investigate the prognostic value of the relative maximum standardized uptake value (SUV) of metastatic lymph node (LN) compared with that of primary tumor (SUV_LN / SUV_Tumor) based on a pretreatment [¹⁸F]-FDG PET/CT scan in patients with clinically node-positive esophageal squamous cell carcinoma (cN+ ESCC) treated with definitive chemoradiotherapy (dCRT). We retrospectively evaluated cN+ ESCC patients who underwent a PET/CT scan before dCRT. Time-dependent receiver operating characteristics analysis was performed to identify the optimal cutoff value for SUV_LN / SUV_Tumor. Prognostic influences of SUV_LN / SUV_Tumor on distant metastasis-free survival (DMFS) and overall survival (OS) were evaluated using the Kaplan-Meier method and log-rank test for univariate analysis and Cox's proportional hazards regression model for multivariate analysis. We identified 112 patients with newly diagnosed cN+ ESCC. After a median follow-up of 32.0 months, 50 (44.6%) patients had distant failure and 84 (75.0%) patients died. Patients with high SUV_LN / SUV_Tumor (≥ 0.39) experienced worse outcomes than low SUV_LN / SUV_Tumor (< 0.39) (two-year DMFS: 26% vs. 70%, p < 0.001; two-year OS: 21% vs. 48%, p = 0.001). Multivariate analysis showed that SUV_LN / SUV_Tumor was an independent prognostic factor for both DMFS (adjusted HR 2.24, 95% CI 1.34-3.75, p = 0.002) and OS (adjusted HR 1.61, 95% CI 1.03-2.53, p = 0.037). Pretreatment of SUV_LN / SUV_Tumor is a simple and useful marker for prognosticating DMFS and OS in cN+ ESCC patients treated with dCRT, which may help in tailoring treatment and designing future clinical trials.

Detecting Pathological Complete Response in Esophageal Cancer after Neoadjuvant Therapy Based on Imaging Techniques: A Diagnostic Systematic Review and Meta-Analysis

INTRODUCTION

Up to 32% of patients with esophageal cancer show a pathological complete response (ypCR) after neoadjuvant therapy. To prevent overtreatment, the indication to perform esophagectomy in these patients should be reconsidered. Implementing an organ-preserving strategy for patients with ypCR requires an accurate assessment of residual disease after neoadjuvant treatment. The aim of this study was to systematically review the effectiveness of imaging techniques used for detection of ypCR after neoadjuvant therapy but before resection in patients with esophageal cancer.

METHODS

A systematic literature search of the Medline, Embase, and Cochrane Library databases was performed from January 1, 2000, to December 13, 2017. Eligible studies were diagnostic studies that compared results of imaging modalities after neoadjuvant therapy to histopathological findings in the resection specimen after esophagectomy. Methodological quality was assessed by the Cochrane Quality Assessment of Diagnostic Accuracy Studies, version 2, model. Primary outcome measures were true positive, false-positive, false-negative, and true negative values of imaging techniques predicting ypCR. A meta-analysis was performed by pooling sensitivities and specificities by using a bivariate model.

RESULTS

A total of 4420 articles were identified. After exclusion of irrelevant titles and abstracts, 360 articles were reviewed in full text. In total, four imaging modalities (computed tomography [CT], positron emission tomography [PET-CT], endoscopic ultrasound [EUS], and magnetic resonance imaging [MRI]) were used for restaging. The meta-analysis was conducted with data from 56 studies involving 3625 patients. The pooled sensitivities of CT, PET-CT, EUS, and MRI for detecting ypCR were 0.35, 0.62, 0.01 and 0.80, respectively, whereas the pooled specificities were 0.83, 0.73, 0.99, and 0.83, respectively. The positive predictive value in detecting ypCR was 0.47 for CT, 0.41 for PET-CT, not applicable for EUS, and 0.61 for MRI.

CONCLUSION

Current imaging modalities such as CT, PET-CT, and EUS seem to be insufficiently accurate to identify complete responders. More accurate diagnostic tests are needed to improve restaging accuracy for patients with esophageal cancer.

Active surveillance in clinically complete responders after neoadjuvant chemoradiotherapy for esophageal or junctional cancer

Neoadjuvant chemoradiotherapy (nCRT) followed by surgery is standard of care for locally advanced esophageal cancer in many countries. After nCRT up to one third of all patients have a pathologically complete response in the resection specimen, posing an ethical imperative to reconsider the necessity of standard surgery in all operable patients after nCRT. An active surveillance strategy following nCRT, in which patients are subjected to frequent clinical investigations after the completion of neoadjuvant therapy, has been evaluated in other types of cancer with promising results. In esophageal cancer, both patients who are cured by neoadjuvant therapy alone as well as patients with subclinical disseminated disease at the time of completion of neoadjuvant therapy may benefit from such an organ sparing approach. Active surveillance is currently applied in selected patients with esophageal cancer who refuse surgery or are medically unfit for major surgery after completion of nCRT, but this strategy is not (yet) adopted as an alternative to standard surgery or definitive chemoradiation. The available literature is scarce, but suggests that long-term oncological outcomes after active surveillance are noninferior compared to standard surgical resection, providing justification for comparison of both treatments in a phase III trial. This review gives an overview of the current knowledge regarding active surveillance after completion of nCRT in esophageal cancer and outlines future research perspectives.