Endoscopic and Imaging Predictors of Complete Pathologic Response After Chemoradiation for 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.

Can Clinical Response Predict Pathologic Response Following Neoadjuvant Chemoradiation for Esophageal Cancer?

OBJECTIVES

Approximately 20-40% of patients with locally advanced esophageal cancer will achieve a pathologic complete response (ypCR) following neoadjuvant chemoradiotherapy (nCRT). Predicting ypCR based on a clinical complete response (ycCR) has been a challenge. This study assessed the correlation between ycCR and ypCR, as determined from esophagectomy specimens.

METHODS

Patients undergoing esophagectomy following nCRT at three major institutions between 2005 and 2018 were reviewed. Restaging, including PET/CT, endoscopy with biopsy, and esophageal ultrasound (EUS), was performed to determine ycCR.

RESULTS

Six hundred sixty patients were included, with 93.3% with esophageal adenocarcinoma histology. Six hundred fifty-eight of these patients underwent PET, 304 EUS, and 584 underwent a biopsy. Following nCRT, 148 (22.4%) were found to have a ypCR. Only 12/32 (37.5%) determined to have a ycCR were found to have a ypCR, while 136/628 (21.6%) with a non-ycCR were found to have a ypCR (p 0.075). Individual modality PPV was 28% for PET, 54% for EUS, and 26% for biopsy. When PET was combined with EUS, 168 reports were concordant and the PPV of ypCR was 50%, though the number of patients was low (1/2). With all 3 re-staging modalities combined, the PPV and NPV both rose to 100%.

CONCLUSIONS

Current restaging tools cannot reliably predict ypCR after nCRT. While multimodal restaging appears to be a more accurate predictor of ypCR than any testing modality alone, patients cannot reliably be advised to avoid an esophagectomy on the assumption that ycCR predicts ypCR at this time.

Different response rates to chemotherapy between Japanese and German esophageal squamous cell carcinoma: patients may be influenced by ERCC1 or ABCB1

Aim: To find out differences in biomarkers between Japanese and German patients responsible for response after neoadjuvant radio/chemotherapy and survival for esophageal squamous cell carcinoma. Materials & methods: A total of 60 patients from Japan and 127 patients from Germany with esophageal squamous cell carcinoma were analyzed according to three SNPs by real-time PCR. Results: The distribution of the genotypes of ERCC1 rs16115 and ABCB1 C3435T rs1045642 was significantly different between both patients' groups. Japanese patients had significantly less good response to 5-fluorouracil/cisplatin chemotherapy. The influence of the three SNPs on response varied between patients from Japan and Germany. Conclusion: Different expressions of ERCC1 and ABCB1 SNPs of Japanese patients compared with the German patients partially explain the different response.

Higher lymph node harvest in patients with a pathologic complete response after neoadjuvant therapy for esophageal cancer is associated with improved survival

BACKGROUND AND OBJECTIVES

Lymph node harvest during esophagectomy has been associated with improved survival for esophageal cancer but the value of enhanced lymph node harvest following complete pathologic response (pCR) is debated. This study investigated if increasing lymph node harvest in esophageal cancer patients with a pCR after neoadjuvant therapy and esophagectomy is associated with improved survival.

METHODS

We queried the National Cancer Data Base for patients with esophageal cancer between 2004 and 2014 who underwent neoadjuvant chemotherapy or chemoradiation therapy followed by esophagectomy found to have pCR. Multivariable Cox modeling was utilized to evaluate the impact of increasing lymph node counts on overall survival (OS).

RESULTS

A total of 1373 patients met inclusion criteria. A National Comprehensive Cancer Network compliant lymphadenectomy of ≥15 nodes was associated with improved survival (66.7% vs 51.1%; P < .001). Cox modeling showed that the first node cutoff to demonstrate a statistically significant improvement in OS was ≥7 nodes (hazard ratio [HR], 95% confidence interval [CI]: 0.81, 0.68-0.97; 5-year OS: 54.2%) with a trend of decreasing and statistically significant HRs until ≥25 nodes (HR, 95% CI: 0.52, 0.37-0.72; 5-year OS: 68.4%).

CONCLUSIONS

High negative node counts after neoadjuvant therapy and esophagectomy are associated with improved survival in patients with pCR.

Definitive Chemoradiotherapy Versus Trimodality Therapy for Resectable Oesophageal Carcinoma: Meta-analyses and Systematic Review of Literature

BACKGROUND

Standard therapy for loco-regionally advanced, resectable oesophageal carcinoma is trimodality therapy (TMT) consisting of neoadjuvant chemoradiotherapy and oesophagectomy. Evidence of survival advantage of TMT over organ-preserving definitive chemoradiotherapy (dCRT) is inconclusive. The aim of this study is to compare survival between TMT and dCRT.

METHODS

A systematic review and meta-analyses were conducted. Randomised controlled trials and observational studies on resectable, curatively treated, oesophageal carcinoma patients above 18 years were included. Three online databases were searched for studies comparing TMT with dCRT. Primary outcomes were 1-, 2-, 3- and 5-year overall survival rates. Risk of bias was assessed using the Cochrane risk of bias tools for RCTs and cohort studies. Quality of evidence was evaluated according to Grading of Recommendation Assessment, Development and Evaluation.

RESULTS

Thirty-two studies described in 35 articles were included in this systematic review, and 33 were included in the meta-analyses. Two-, three- and five-year overall survival was significantly lower in dCRT compared to TMT, with relative risks (RRs) of 0.69 (95% CI 0.57-0.83), 0.76 (95% CI 0.63-0.92) and 0.57 (95% CI 0.47-0.71), respectively. When only analysing studies with equal patient groups at baseline, no significant differences for 2-, 3- and 5-year overall survival were found with RRs of 0.83 (95% CI 0.62-1.10), 0.81 (95% CI 0.57-1.14) and 0.63 (95% CI 0.36-1.12).

CONCLUSION

These meta-analyses do not show clear survival advantage for TMT over dCRT. Only a non-significant trend towards better survival was seen, assuming comparable patient groups at baseline. Non-operative management of oesophageal carcinoma patients might be part of a personalised and tailored treatment approach in future. However, to date hard evidence proving its non-inferiority compared to operative management is lacking.