Mucoepidermoid carcinoma of the pancreas: a case report and a review of literature
A 63-year-old woman was admitted to our hospital, following a 5-year history of left upper abdominal pain and abdominal distension (The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China, 2011). Computed tomography (CT) scan performed by a local physician 1 week before admission revealed suspected pancreatic cancer. She was then referred to our hospital for further examination and treatment. At the time of admission, she complained of loss of appetite and nausea, but no jaundice was found. Her abdomen was slightly distended and tympanitic. No remarkable mass was found in abdomen by physical examination. The serum levels of carbohydrate antigen 19-9 (CA19-9) was elevated at 500.1U/ml (with normal range less than 37 U/ml). The serum level of carcinoembryonic antigen (CEA), squamous cell carcinoma antigen, alpha-fetoproteins, and neuron-specific enolase were not elevated. Computed tomography scan revealed a solid mass, approximately 4.5 cm in diameter, located at the left upper abdomen. The tumor was irregular in shape, and appeared to arise from the distal pancreas []. Meanwhile, a splenic artery aneurysm existed [].\nA laparotomy was performed and we found that the tumor arised from the pancreatic body and tail without breaking pancreatic capsule. Meanwhile, a splenic artery aneurysm was found near celiac trunk. The distal pancreas, spleen, and its aneurysm were resected [Figures and ]. Intraoperative frozen section of the specimen showed the proximal pancreatic margin was negative.\nOn pathologic examination, the size and the cut surface showed a milky-white solid and homogeneous tumor with a hard elastic consistency. The tumor consisted of three types of cells, the majority being poorly differentiated adenocarcinoma cells with mucin products in their cytoplasm, and some moderately differentiated adenocarcinoma with a tendency to form ducts. In addition, there were epidermoid cells and intermediate undifferentiated cells. These epidermoid cells did not have definite intercellular bridges, keratohyaline, or keratin pearls. No differentiated squamous carcinoma cells were detected in any part of the tumor [].\nThe cells of the tumor showed strong staining with antibodies to CK7, CK5/6, and CEA, showed negative staining for CK20, the proliferation index by Ki-67 stain was above 30%. The final pathology diagnosis was mucoepidermoid carcinoma. The postoperative course was uneventful and the patient was discharged 2 weeks after the surgery. Gemcitabine was used once but the patient had severe gastrointestinal side-effects, then she underwent oral Xeloda for five cycles. However, CA19-9 and CEA were elevated 5 months after operation. She survived for 12 months after surgery.