Previous cholecystectomy, gastrectomy, and diabetes mellitus are not crucial risk factors for pancreatic cancer in patients with chronic pancreatitis

Introduction: In the general population, cholecystectomy, diabetes, and chronic pancreatitis seem to be associated with an increased risk of developing pancreatic cancer. Aims: We assessed whether previous cholecystectomy, gastrectomy, or diabetes mellitus may be risk factors for pancreatic cancer in patients with chronic pancreatitis. Methodology: We analyzed 853 patients with chronic pancreatitis (110 women, 743 men) with a median follow-up period of 14 years with particular reference to establishing which patients had previously undergone cholecystectomy or distal gastric resection (Billroth II anastomosis) or had diabetes or gallstone disease and the respective time scales involved. Results: Pancreatic cancer developed in 17 patients with chronic pancreatitis after a median period of 8 years from onset of pancreatitis symptoms (range, 3-38 years). Excluding two cholecystectomies performed 1 year before diagnosis of cancer, cholecystectomy was performed in 7/17 (41%) patients with pancreatic cancer and in 381/836 (46%) of the other patients with chronic pancreatitis. Forty-nine (10%) patients with chronic pancreatitis and no pancreatic cancer had undergone cholecystectomy during the years before the onset of chronic pancreatitis, whereas none of the patients in whom a pancreatic malignancy developed had undergone cholecystectomy before the onset of chronic pancreatitis symptoms. Gastrectomies were performed in 116 patients (14%), 47 before the onset of chronic pancreatitis. Only 2/17 patients with pancreatic cancer had undergone previous gastrectomy, though in both cases only shortly before diagnosis of the cancer. Diabetes was diagnosed in 353 patients, but only in 30 (4%) before onset of chronic pancreatitis. Only 1/17 patients (6%) with pancreatic cancer had long-standing diabetes, whereas diabetes developed in 3/17 shortly before diagnosis of pancreatic cancer. Conclusions: Cholecystectomy, gastrectomy, and diabetes are not major risk factors for the development of pancreatic cancer in patients with chronic pancreatitis.