Combination Chemotherapy With or Without Ganitumab in Treating Patients With Previously Untreated Metastatic Pancreatic Cancer

RATIONALE: Drugs used in chemotherapy, such as fluorouracil, leucovorin calcium, irinotecan hydrochloride, and oxaliplatin, work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing. Monoclonal antibodies, such as ganitumab, can block tumor growth in different ways. Some block the ability of tumor cells to grow and spread. Others find tumor cells and help kill them or carry cancer-killing substances to them. It is not yet known whether giving more than one drug (combination chemotherapy) is more effective with or without ganitumab in treating patients with pancreatic cancer. PURPOSE: This phase I/II trial is studying the best dose of combination chemotherapy and ganitumab and how well combination chemotherapy with or without ganitumab works in treating patients with previously untreated metastatic pancreatic cancer.