Patient description: The patient is a 41-year-old obese woman coming to the emergency room with abdominal pain and vomiting. The pain that started gradually yesterday is located in the epigastric and periumbilical regions, radiating to her back. She drinks alcohol frequently and does not smoke. She has no history of allergies and uses only multivitamins daily. Her family history is positive for hypertension (her mother). She lives with her husband and has 3 children. The abdomen is tender and soft. Her bowel sounds are normal. Her heart rate is 115/min and blood pressure 110/75 mmHg. The lab studies are remarkable for leukocytosis (19.5), urea of 8.5, high CRP (145), high amylase (1200) and Glucose level of 15. Her abdominal CT scan revealed acute edematous interstitial pancreatitis with enlarged common bile duct and intrahepatic duct confirming gall stone pancreatitis. Her pregnancy test is negative and she is not breastfeeding.

Clinical trial eligibility criteria: eligible ages (years): 18.0-999.0,  Acinar Cell Adenocarcinoma of the Pancreas Adenocarcinoma of the Gallbladder Adenocarcinoma of Unknown Primary Adult Primary Cholangiocellular Carcinoma Advanced Adult Primary Liver Cancer Cholangiocarcinoma of the Extrahepatic Bile Duct Cholangiocarcinoma of the Gallbladder Diffuse Adenocarcinoma of the Stomach Duct Cell Adenocarcinoma of the Pancreas Intestinal Adenocarcinoma of the Stomach Localized Unresectable Adult Primary Liver Cancer Metastatic Carcinoma of Unknown Primary Metastatic Extrahepatic Bile Duct Cancer Mixed Adenocarcinoma of the Stomach Mucinous Adenocarcinoma of the Colon Mucinous Adenocarcinoma of the Rectum Newly Diagnosed Carcinoma of Unknown Primary Signet Ring Adenocarcinoma of the Colon Signet Ring Adenocarcinoma of the Rectum Stage III Pancreatic Cancer Stage IIIA Colon Cancer Stage IIIA Gallbladder Cancer Stage IIIA Gastric Cancer Stage IIIA Rectal Cancer Stage IIIB Colon Cancer Stage IIIB Gallbladder Cancer Stage IIIB Gastric Cancer Stage IIIB Rectal Cancer Stage IIIC Colon Cancer Stage IIIC Gastric Cancer Stage IIIC Rectal Cancer Stage IV Gastric Cancer Stage IV Pancreatic Cancer Stage IVA Colon Cancer Stage IVA Gallbladder Cancer Stage IVA Rectal Cancer Stage IVB Colon Cancer Stage IVB Gallbladder Cancer Stage IVB Rectal Cancer Unresectable Extrahepatic Bile Duct Cancer Histologically or cytologically confirmed locally advanced or metastatic pancreatic adenocarcinoma, colorectal adenocarcinoma, gastric adenocarcinoma, cholangiocarcinoma, gall bladder adenocarcinoma, ampullary carcinoma, adenocarcinoma of unclear primary (with a gastrointestinal primary suspected), or other primary gastrointestinal malignancy for which the treating physician feels that mFOLFIRINOX is a reasonable therapeutic option Amendment (January 2014): only subjects with the following histologies will be eligible Cohort # 1 (pancreatic cohort): locally advanced or metastatic pancreatic adenocarcinoma (19 subjects evaluable for the primary endpoint after the amendment) Cohort #2 (biliary tract cohort): locally advanced or metastatic cholangiocarcinoma, gall bladder adenocarcinoma, or ampullary carcinoma (19 subjects evaluable for the primary endpoint after the amendment). Patients with adenocarcinoma of unclear primary that are most likely of biliary tract origin (in the opinion of the treating physician) will also be allowed on this cohort Patients with a history of obstructive jaundice due to the primary tumor must have a metal biliary stent in place Eastern Cooperative Oncology Group (ECOG) performance status =< 1 Life expectancy > 3 months Absolute neutrophil count (ANC) >= l500/ul Hemoglobin >= 9g/dL Platelets >= 100,000/ ul Total bilirubin < 1.5 x upper limit of normal Serum glutamic oxaloacetic transaminase (SGOT) and serum glutamic pyruvate transaminase (SGPT) < 2.5 x upper limit of normal for patients without liver metastases OR SGOT and SGPT < 5 x upper limit of normal for patients with liver metastases  Prior chemotherapy or radiation therapy for any cancer Inflammatory bowel disease (Crohn's disease, ulcerative colitis) Diarrhea, grade 1 or greater by the National Cancer Institute Common Terminology for Adverse Events (NCI-CTCAE, v. 4.0); pancreatic cancer patients with clinical evidence of pancreatic insufficiency must be taking pancreatic enzyme replacement Neuropathy, grade 2 or greater by NCI-CTCAE, v. 4.0 Documented brain metastases Serious underlying medical or psychiatric illnesses that would, in the opinion of the treating physician, substantially increase the risk for complications related to treatment Active uncontrolled bleeding Pregnancy or breastfeeding Major surgery within 4 weeks Previous or concurrent malignancy, except for adequately treated basal cell or squamous cell skin cancer, in situ cervical cancer, or any other cancer for which the patient has been previously treated and the lifetime recurrence risk is less than 30%