ChemoTherapy aNd chemoradioTherapy for adenocarcinoma of the OESophagus and esophagogastric junction with oligometastases: Protocol of the TNT-OES-1 trial

Background: FLOT and CROSS are effective neoadjuvant regimens for esophageal cancer patients. Chemotherapy (FLOT) is aimed to have merely a systemic effect whereas neoadjuvant chemoradiotherapy (CROSS) achieves good locoregional response with clinically complete response (cCR) rates up to 33% [1]. The aim of the present study is to assess safety and feasibility of dual therapy (FLOT-CROSS) in patients with oligometastases.Methods: This phase-II single-center, single-arm, intervention study includes patients with oligometastatic adenocarcinoma of the esophagus or esophagogastric junction. Patients will be treated with four biweekly cycles of FLOT, consisting of intravenous fluorouracil (2600 mg/m2), leucovorin (200 mg/m2), oxaliplatin (85 mg/m2) and docetaxel (50 mg/m2). Response evaluation by CT-scan will be performed 4-6 weeks after completion of FLOT. In case of regression or stable disease according to RECIST criteria (v.1.1), patients will receive additional CROSS, consisting of five weekly cycles of intravenous carboplatin (AUC 2) and paclitaxel (50 mg/m2), with concurrent 41.4 Gy radiotherapy, in 23 daily fractions of 1.8 Gy [2]. Response evaluation by endoscopy with biopsies, endoscopic ultrasonography and CT-scan will be performed 4-6 weeks after completion of CROSS. Primary endpoint is tolerability of FLOT-CROSS, defined as the proportion of patients who complete the full regimen. Secondary endpoints include disease control rate, objective response rate, overall survival and progression-free survival. In total, 20 patients will be included.Discussion: If patients are able to complete and tolerate FLOT-CROSS, this regimen should be tested in a phase-III trial and as neoadjuvant treatment in patients with locally advanced non-metastatic esophageal or junctional adenocarcinoma.