Giotto Biotech S.R.L. 1 article published in JoVE Cancer Research Isolation of Proximal Fluids to Investigate the Tumor Microenvironment of Pancreatic Adenocarcinoma Greta Donisi*1, Marialuisa Barbagallo*2, Giovanni Capretti1,3, Gennaro Nappo1,3, Panteleimon G. Takis4,5,6, Alessandro Zerbi1,3, Federica Marchesi2,7, Nina Cortese2 1Section of Pancreatic Surgery, Humanitas Clinical and Research Center-IRCCS, 2Department of Immunology and Inflammation, Humanitas Clinical and Research Center-IRCCS, 3Department of Biomedical Sciences, Humanitas University, 4Giotto Biotech S.R.L., 5Section of Bioanalytical Chemistry, Division of Systems Medicine, Department of Metabolism, Digestion and Reproduction, Imperial College London, 6National Phenome Centre, Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, 7Department of Medical Biotechnology and Translational Medicine, University of Milan Pancreatic juice is a precious source of biomarkers for human pancreatic cancer. We describe here a method for intraoperative collection procedure. To overcome the challenge of adopting this procedure in murine models, we suggest an alternative sample, tumor interstitial fluid, and describe here two protocols for its isolation.