2548 Jejunal Perforation: A Very Rare Presentation of Jejunal Adenocarcinoma

Abstract

INTRODUCTION: Small bowel malignancies constitute less than 5% of all gastrointestinal malignancies. The most common histological types of small bowel cancer are adenocarcinoma, neuroendocrine cancer, lymphoma and sarcoma. Adenocarcinoma represents 25-40% of primary small bowel malignancies, with the highest incidence in the duodenum and the incidence progressively decreasing down the small intestine. CASE DESCRIPTION/METHODS: A 69 year old previously healthy women presented with periumbilical pain for four weeks. She also reported early satiety but no weight loss. The night prior to presentation abdominal pain became severe with one episode of vomiting. There was no history of chronic NSAIDs use. She had a 40 pack-years smoking history. She had two cesarean sections and a total abdominal hysterectomy with bilateral salpingo-opherectomy. She did not have routine colorectal cancer screening. On abdominal examination she had a distended abdomen and mild periumbilical tenderness. Laboratory testing revealed leukocytosis of 15000/µL and a hemoglobin level of 10.2 g/dl with a low MCV 78.6 fl. Noncontrast CT of the abdomen showed wall thickening and focal perforation in a loop of jejunum. There was no bowel obstruction and no free intraperitoneal air seen. Exploratory laparotomy revealed a large inflammatory mass in the proximal jejunum densely adherent to the mid-transverse colon. There was a large perforation (3.5 cm of greatest dimension) of a jejunal mass. The mucosa surrounding the defect was hyperemic and thickened. Microscopic examination showed a well-differentiated adenocarcinoma invading into muscularis propria. There was no lymphovascular invasion and no metastasis were identified in 13 excised regional lymph nodes. Immunostains were negative for cytokeratin 7 (expressed in lung and pancreatic adenocarcinomas), focally positive for cytokeratin 20 (colorectal adenocarcinoma) and were positive for CDX2. CDX2 is a highly sensitive and specific marker of adenocarcinoma of intestinal origin. DISCUSSION: Jejunal adenocarcinoma is an extremely rare GI malignancy. The clinical presentation is often with abdominal pain and distension; only 10% present as a bowel perforation. Surgical resection is considered curative treatment for localized adenocarcinoma. Oxaliplatin-based adjuvant chemotherapy is suggested for patients with lymphovascular invasion. In our patient perforation per se was considered a high-risk feature and the patient was advised to have post-operative adjuvant chemotherapy.