O089 Relationship of metformin with the risk of pancreatic cancer in patients with diabetes and/or chronic pancreatitis: a systematic review

Abstract

Abstract Introduction Metformin is the first-line treatment in patients with Type 2 diabetes. However, controversy exists regarding its role in reducing the risk of pancreatic cancer or improving pancreatic cancer survival in patients with Type 2 diabetes or chronic pancreatitis. This systematic review aimed to define the risk of pancreatic cancer and survival from pancreatic cancer in patients with diabetes or chronic pancreatitis receiving metformin. Methods Systematic searches of Medline and Cochrane Library databases were undertaken to identify studies reporting on the use of metformin and its impact on pancreatic cancer risk and/or survival in patients with diabetes or chronic pancreatitis. Results Thirty studies, reporting on a total of 5,969,712 patients (1,362,308 with diabetes or chronic pancreatitis, and 4,597,095 controls), were included. Eleven studies assessed the risk of developing pancreatic cancer. Of these, six found a significant reduction in the risk of developing pancreatic cancer in those taking metformin, whereas five studies found no such reduction in pancreatic cancer risk. Another 19 studies evaluated the impact of metformin on pancreatic cancer survival. Twelve of these found evidence of benefit in those receiving metformin, whereas seven found no survival benefit. Formal pooling could not be undertaken due to high statistical and clinical heterogeneity. Conclusion The relationship between the use of metformin and the incidence of pancreatic cancer is complex and multifactorial. However, the currently available evidence is not sufficient for definitive conclusions on this relationship. Take-home message Current evidence is not robust enough to recommend the use metformin as prophylaxis for pancreatic cancer or to improve survival in patients with pancreatic cancer.