Teaching Case

Patient with melena, anemia and left upper quadrant mobile mass on palpation.

The patient was admitted to hospital with melena, 7 episodes during the last 30 hours. He had a history of duodenal ulcer and two episodes of GI bleeding 24 and 26 months ago that were attributed to the duodenal ulcer. Physical examination revealed a mobile mass in the left upper quadrant. Gastroscopy and total colonoscopy were unremarkable. Routine laboratory tests revealed only anemia (Hct 34%). The patient underwent upper abdominal US, abdominal CT, enteroclysis and abdominal MRI.

Small bowel leiomyosarcomas are uncommon malignant mesenchymal tumors that account for less than 15% of all primary intestinal malignancies[1-3]. On US the tumor appeared as a large hypoechoic mass with central area of high reflectivity. CT showed a soft tissue mass with central cavitation that was filled with oral contrast. Enteroclysis revealed a large extraluminal mass, originating from the jejunal wall and displacing adjacent loops. A central cavitated area communicating with the intestinal lumen through a fistula was also demonstrated. No mucosal abnormality was noted. On MRI the mass was of intermediate signal intensity, similar to that of muscles on T1-w images, of moderate to high signal on T2-w images and exhibited significant homogeneous enhancement on postgadolinium T1-w images. In the central cavitated area a small amount of orally given contrast was seen. Involvement of adjacent organs, lymph node enlargement or distant metastatic deposits were not disclosed by any imaging modality. The US, CT and enteroclysis findings in our case were rather typical for leiomyosarcoma and have been previously described [1-4]. The communication of the central necrotic area with the intestinal lumen may not be easily demonstrated on imaging studies.Differential diagnosis includes small bowel lymphoma, usually presented with excavation or a grossly ulcerated mass involving a segment of the bowel with no extra-intestinal component,accompanied by lymphadenopathy, adenocarcinoma, characterized by an annular,constricting lesion with mucosal destruction and ulceration, carcinoid tumor, almost invariably associated with desmoplastic reaction, and leiomyoma that is usually smaller in size,with superficial or no ulceration.Imaging is of importance in revealing and characterizing intestinal leiomyosarcomas.