RESUMEN
A case of cholestasis due to a synchronous pancreatic head metastasis from an occult lobular breast carcinoma is presented. The patient had a clinical and radiological picture compatible with a pancreatic head primary tumor with cholestasis and ascites. Ultrasonographically guided fine needle aspiration cytology demonstrated a metastatic breast lobular cancer (positive for cytokeratin AE1 and AE3, cytokeratin 7 and epithelial membrane antigen and negative for cytokeratin 20, CA 19.9, CA 125, CEA and estrogenic receptors). The same cytologic findings were observed in skin and subcutaneous armpit nodules. Clinical and radiological breast examination was unable to demonstrate any tumor in the breast. Pancreatic metastases are rare events and the majority of them are secondary to renal and lung cancer and rarely to breast cancer. In these latter cases, metastases are usually disclosed after a disease-free interval of months or years between primary tumor resection and recognition of the pancreatic tumor. Synchronous presentation is extremely rare. Metastases of epithelial origin are uncommon in pancreas and generally are first misdiagnosed as primary pancreatic cancer. Fine needle aspiration is a useful tool for the differential diagnosis in patients with widespread disease.