Genetically Determined Chronic Pancreatitis but not Alcoholic Pancreatitis Is a Strong Risk Factor for Pancreatic Cancer

Objective To study if chronic pancreatitis (CP) is a risk factor for pancreatic cancer. Methods Through a cohort and a case-control study design, CP and other important risk factors including smoking, diabetes, alcohol, obesity, and genetic mutations were studied for their association with pancreatic cancer. Results In the cohort study, 402 patients with CP were included. During 3967.74 person-years of exposure, 5 of the 402 patients (4 idiopathic CP, 1 hereditary CP) developed pancreatic cancer after 16.60 3.51 years of CP. The standardized incidence ratio was 121. In the case-control study, 249 pancreatic cancer patients and 1000 healthy controls were included. Of the 249 patients with pancreatic cancer, 24 had underlying idiopathic CP, and none had alcoholic pancreatitis. SPINK1 gene mutation was present in 16 of 26 patients with idiopathic CP who had pancreatic cancer. Multivariable analysis showed CP (odds ratio [OR], 97.67; 95% confidence interval [CI], 12.69-751.36), diabetes (>4 years duration) (OR, 3.05; 95% CI, 1.79-5.18), smoking (OR, 1.93; 95% CI, 1.38-2.69) as significant risk factors for pancreatic cancer. The population attributable risk was 9.41, 9.06, and 9.50 for diabetes, CP, and smoking, respectively. Conclusions Genetically determined CP but not alcoholic CP is a strong risk factor for pancreatic cancer.