Unexpected Etiology of Ascites in Disseminated Small Bowel Neuroendocrine Tumor Patient Diagnosed and Treated by Interventional Radiological Techniques

A case of ascites developed in disseminated neuroendocrine small bowel tumor G1 (Ki-67 2 %) patient due to the unlikeliest of the possible reasons, i.e. iatrogenic mesenteric arterioportal fistula, is presented in the paper. The patient after palliative small bowel resection was preparing for the liver transarterial chemoembolization (TACE) when the fluid accumulation was revealed in the peritoneal cavity at ultrasound and MR imaging. The probable ascites etiologies (peritoneal carcinomatosis, carcinoid right heart failure, portal hypertension due to tumor compression or vascular elastic fibrosis) were consistently ruled out. The fistulation between the superior mesenteric arterial branch and the superior mesenteric vein developed shot after small bowel surgery and maintaining portal ascites was occasionally found at superior mesentericography. The ascites vanished after fistula occlusion with the metal coils, and the patient proceeded to the planned liver TACE therapies with good effect.