After neoadjuvant chemoradiotherapy (nCRT) for esophageal cancer, high pathologically complete response (pCR) rates are being achieved in patients with squamous cell carcinoma (SCC). An active surveillance strategy has been proposed for SCC patients with clinically complete response (cCR) after nCRT. To justify omitting surgical resection, patients with residual disease should be accurately identified.~The objective of this study is to assess the accuracy of response evaluations after nCRT based on the preSANO trial, including positron emission tomography with computed tomography (PET-CT), endoscopic bite-on-bite biopsies and endoscopic ultrasonography (EUS) with fine-needle aspiration (FNA) in patients with potentially curable esophageal SCC.~Operable esophageal SCC patients who are planned to undergo nCRT according to the CROSS regimen and are planned to undergo surgery will be recruited from four Asian centers. Four to six weeks after completion of nCRT, patients will undergo a first clinical response evaluation (CRE-1) consisting of endoscopic bite-on-bite biopsies. In patients without histological evidence of residual tumor (i.e. without positive biopsies), surgery will be postponed another six weeks. A second clinical response evaluation (CRE-2) will be performed 10-12 weeks after completion of nCRT, consisting of PET-CT, endoscopic bite-on-bite biopsies and EUS with FNA. Immediately after CRE-2 all patients without evidence of distant metastases will undergo esophagectomy. Results of CRE-1 and CRE-2 as well as results of single diagnostic modalities will be correlated to pathological response in the resection specimen for calculation of sensitivity, specificity, negative predictive value and positive predictive value.~If the current study shows that major residual disease (>10% residual carcinoma at the primary tumor site and any residual nodal disease) can be accurately (i.e. with sensitivity of 80.5%) detected in patients with esophageal SCC, a prospective trial will be conducted comparing active surveillance with standard esophagectomy in patients with a clinically complete response after nCRT (SINO trial).
Prospective, multi-centre, diagnostic cohort study investigating the accuracy of positron emission tomography with computed tomography (PET-CT), endoscopic bite-on-bite biopsies and endoscopic ultrasonography (EUS) with fine-needle aspiration (FNA) for detecting residual disease after neoadjuvant chemoradiotherapy in patients with potentially curable esophageal squamous cell carcinoma (SCC).