A Case of Primary Adenosquamous Cell Carcinoma of the Jejunum

A 64-year-old woman visited a medical clinic complaining of general fatigue, and was referred to our hospital because of an abdominal mass and anemia. Her serum CEA and CA19-9 levels were 21.7 ng/ml and 155.9 U/ml, respectively. An upper GI series revealed stenosis of the jejunum approximately 8 cm distal to Treitz's ligament, and a barium enema study showed a stenotic portion in the transverse colon. Under the tentative diagnosis of a jejunal tumor laparotomy was performed, and partial resection of the jejunum with lymph node dissection combined with right hemicolectomy was carried out. Macroscopically, the jejunal tumor had a small ulceration, forming an exrtaluminal mass about 8 cm in diameter, and involved the transverse colon. Histological examination revealed areas of adenocarcinoma forming moderately differentiated tumor glands, and areas of squamous cell carcinoma with mild keratinization showing sheet-like tumor growth. The patient died 32 months postoperatively, bearing liver metastases found in the 22nd postoperative month. Adeno-squamous cell carcinoma of the small bowel is very rare, and the present case appears to be the second reported from Japan.