Multifocal angiosarcoma of the gastrointestinal tract:a case report.

An 80-year-old man presented to our hospital with complaints of tarry stool and shortness of breath. A blood test confirmed marked anemia. On abdominal contrast-enhanced computed tomography, neither hemorrhagic lesions nor tumorous lesions could be pointed out. Upper gastrointestinal endoscopy revealed multiple erythematous flat elevated lesions, which were about 10mm in diameter, located between the stomach and the horizontal part of the duodenum. Colonoscopy revealed similar lesions throughout the entire colon. Pathological examination of biopsy specimens demonstrated the proliferation of neoplastic cells positive for immunostaining of factor VIII-related antigen, CD31, and CD34. Accordingly, the patient was diagnosed with angiosarcoma of the gastrointestinal tract. Although the patient was transferred to another hospital for chemotherapy, he died shortly after the transfer because of deterioration of his bleeding symptoms. Angiosarcoma is a soft-tissue neoplasm of vascular endothelium origin, accounting for less than 2% of all sarcomas. It usually occurs in the skin of the head and neck and in soft tissues. Angiosarcoma of the gastrointestinal tract is rare and is described only in case reports and small series. These tumors are characterized by an extremely aggressive course, with a high tendency to metastasize, leaving patients with a poor prognosis. When angiosarcoma is found in multiple sites of the gastrointestinal tract, it is sometimes difficult to differentiate between primary and metastatic occurrences. We analyzed reported cases of multifocal angiosarcoma of the digestive tract, of which there are 43 so far. In 24 cases, the angiosarcoma was thought to originate from the gastrointestinal tract (primary angiosarcoma). In 13 cases, angiosarcoma of other organs metastasized to the digestive tract (metastatic angiosarcoma). In the remaining 6 cases, whether the multifocal angiosarcoma of the digestive tract was primary or metastatic was unclear. In the current case, no primary lesion was found outside the gastrointestinal tract. Therefore, he was diagnosed with primary multifocal angiosarcoma.

[Neuroendocrine tumor of the terminal ileum observed by magnifying endoscopy with narrow-band imaging: a case report].

We report the case of an 88-year-old woman with localized intestinal obstruction caused by a midgut neuroendocrine tumor (NET) without endocrine symptoms. She was referred to our hospital for lower abdominal pain. Abdominal enhanced computed tomography revealed a thickened wall in the terminal ileum with dilated small bowel and multiple hepatic metastases upstream. Although the presenting symptoms resolved with short-term fasting and defecation, we performed further investigation. Colonoscopy confirmed the presence of submucosal tumors in the terminal ileum with a yellow-discolored surface but without ulceration or erosion. Magnifying endoscopy with narrow-band imaging clearly showed extended and dilated vessels, with the existing vessels maintained under the epithelium. Biopsies from these lesions were immunohistochemically positive for all neuroendocrine markers, and the Ki-67 index was 10%. Therefore, the patient was diagnosed with NET, and she underwent laparoscopic surgery to relieve the intestinal obstruction. Pathological examination of the resected specimen confirmed grade 2 NET with intramural metastasis and dissemination. After follow-up for a month, octreotide long-acting repeatable therapy was initiated and the patient was free of symptoms at the 6-month follow-up. This is the first report of midgut NET observed by magnifying endoscopy with narrow-band imaging.

[Obstructive colitis following the ingestion of laxatives during bowel preparation for colonoscopy: a report of two cases].

The first case of obstructive colitis (OC) was observed in a 71-year-old man who presented to our hospital complaining of frank blood in the stool. After receiving a laxative for bowel preparation, he complained of lower abdominal pain. Colonoscopy revealed a circumferential tumor at the rectosigmoid junction. Diffuse erythema with erosion and ulceration was observed 5cm proximal to the tumor. The second case of OC was observed in a 73-year-old man. He was admitted to our hospital for endoscopic resection of a colonic polyp. After receiving a laxative for bowel preparation, he complained of lower abdominal pain. Colonoscopy revealed that the rectum was filled with feces. Diffuse erythema with ulceration was observed in the part beyond the feces. In both cases, although the cause of the obstruction differed, the obstructing lesions were located at the rectum, and the OC appeared to be induced by laxative ingestion.

Late Migration of Covered Metal Stent to the Stomach Through a Spontaneous Choledochoduodenal Fistula in a Patient With Malignant Biliary Obstruction.

We report a case in which a spontaneous choledochoduodenal fistula occurred after biliary covered self-expanding metal stent (SEMS) placement and a late transfistula migration of the stent in a patient with malignant distal biliary obstruction. A partially covered WallFlex biliary stent (Boston Scientific) was appropriately implanted in the common bile duct. Subsequently the patient received chemotherapy with gemcitabine. After 7 months of the SEMS insertion, the patient presented with frequent vomiting. Abdominal computed tomography revealed the obstruction of the duodenal descending part and the migrated stent in the stomach. A choledochoduodenal fistula was observed endoscopically at the proximal point of the duodenal obstruction. These findings can cleanly account for the SEMS migration through the fistula. The mechanism of formation of the fistula is mostly associated with a mechanical contact between the bile duct wall and the SEMS edge, which is pushed up in the direction of the duodenum because of the enlargement of the primary tumor, finally penetrating through the duodenal wall. To our knowledge, this is an extreme unusual case, which has been unreported previously. Therefore, we emphasize the necessity of being alert to the potential for such complications in cases involving placement of SEMS for malignant biliary obstruction.