Fig. 2From: Combination of gemcitabine, nab-paclitaxel, and S-1(GAS) as the first-line treatment for patients with locally advanced or advanced pancreatic ductal adenocarcinoma: study protocol for an open-label, single-arm phase I studyOverview of four phases of the trial. CA 199, carbohydrate antigen 199; CA 125, carbohydrate antigen 125; CEA, carcinoembryonic antigen; CT, computer tomography; MRI, magnetic resonance imaging; ECOG PS, Eastern Cooperative Oncology Group performance status; GAS, nab-paclitaxel/gemcitabine/S-1Back to article page