Asymptomatic acute pancreatitis due to tamoxifen-induced severe hypertriglyceridemia in a patient with diabetes mellitus and breast cancer.

We report tamoxifen-induced hypertriglyceridemia and asymptomatic acute pancreatitis in a 51 year-old women with type 2 diabetes mellitus and stage III-b infiltrative ductal carcinoma, admitted to the hospital with weakness, oliguria and glucose dysregulation. On admission, there was no fever, abdominal or back pain, rebound tenderness, nausea, or vomiting. Following 1 year of tamoxifen treatment, triglycerides increased from 400 to 1344 mg/dl (blood urea nitrogen 52 mg/dl, creatinine 2.0 mg/dl, glucose 341 mg/dl). Hypertriglyceridemia was considered to be due to either diabetic dyslipidemia and/or tamoxifen. On computerized tomography, pancreatic enlargement, heterogenity, hypodensity and a pancreatic pseudocyst (5 x 7.5 cm diameter) were found. Acute pancreatitis was suspected, and serum amylase level was found to be increased (273 IU/L). Tamoxifen was discontinued and gemfibrozil was started. Triglycerides decreased to 301 mg/dl and amylase decreased to 66 IU/L a week later and remained normal thereafter. This case indicates that tamoxifen-induced hypertriglyceridemia may cause acute pancreatitis without classical symptoms which might be due to autonomic neuropathy in diabetic patients. Effects on lipid metabolism should be considered and triglycerides should be closely followed in patients on tamoxifen.