Adjuvant Chemotherapy After Curative Intent Resection of Ampullary Cancer (ADAPTA): Study Protocol for a Pan-European Prospective Multicenter Double Single Arm Trial

Objectives: Ampullary adenocarcinoma (AAC) is rare. Five-year survival rates of 30% to 70% are seen after resection. This broad range of survival could be explained by the morphologic heterogeneity in the 3 subtypes of AAC (pancreatobiliary, intestinal, and mixed subtype), which complicates the prediction of individual prognosis and clinical decision making with regard to adjuvant therapy. To date, there are no prospective studies to elucidate whether adjuvant chemotherapy improves survival in these patients. Methods: The ADAPTA study is a phase II prospective single-arm multicenter cohort study including 200 patients with resected AAC (100 patients with intestinal subtype, and 100 with pancreatobiliary- and mixed subtype). All patients will be treated with CAPOX/ FOLFIRINOX, respectively. Outcomes will be compared after propensity score matching to the data of all patients in consecutive participating centers not treated according to the proposed regime. Conclusions: This pioneering prospective study aims to generate evidence on the impact of adjuvant chemotherapy tailored to the histopathologic subtypes of AAC. The outcomes of this trial could lead to changes in clinical guidelines or pave the way for future randomized controlled trials. Trial registration: ClinicalTrials.gov Identifier: NCT06068023.