Inferior mesenteric arteriovenous fistula during treatment with bevacizumab in colorectal cancer patient: A case report

Figure 1 Colonoscopy showed abnormal colonic edematous mucosa with multiple ulcers from the sigmoid colon, distal to the anastomotic site, to the rectosigmoid colon and rectum below the peritoneal reflection. A: Mild inflammation in the anastomotic site; B: Severe inflammation with multiple ulcers and edematous mucosa in the sigmoid colon; C: Rectum below the peritoneal reflection with almost normal findings.

Figure 2 Abdominal contrast-enhanced computed tomography at 5 year after left hemicolectomy and at 1 year after the start of palliative chemotherapy. A: Computed tomography (CT) showed edematous change from the sigmoid colon to the rectum (triple arrow); B: An aneurysm adjacent to the inferior mesenteric vein (IMV) (arrow); C: Multidetector CT angiography (three-dimensional volume-rendered image) showed the arteriovenous fistula with nidus involving the branches of the inferior mesenteric artery and IMV.

Figure 3 An elective angiography of the inferior mesenteric artery. A: Angiography revealed the nidus of fistula supplied by the inferior mesenteric artery (IMA) (arrow head); B: Several shunting points of the fistula from the branch of the IMA (arrows), which confirmed the existence of an inferior mesenteric arteriovenous fistula (IMAVF); C: The IMAVF completely disappeared after arterial embolization. IMV: Inferior mesenteric vein.