- An 86-year-old man without significant comorbidity presented with weight loss, diarrhea, and iron deficiency anemia. No signs of gastrointestinal bleeding were noticed. Colonoscopy was performed, and sigmoid cancer was suspected (a). Biopsies were obtained, which confirmed colonic adenocarcinoma. Eight hours after the endoscopy, the patient developed massive hematochezia, followed by hemodynamic instability (blood pressure 60/30 mm Hg; heart rate 120 bpm; and hemoglobin drop from 9.8 g/dL to 6.1 g/dL within 2 hours). After stabilization with intravenous fluids, norepinephrine, and transfusion of 1 unit of red blood cells, endoscopy was repeated and ruled out ongoing bleeding. A computed tomography scan confirmed a mass of the sigmoid colon, which extended along the inferior mesenteric artery and to the os sacrum. Within the sigmoid wall, extravasation of the contrast medium was seen into a structure of 2.3 × 1.7 cm. Computed tomography reconstructions suspected pseudoaneurysm of theAn 86-year-old man without significant comorbidity presented with weight loss, diarrhea, and iron deficiency anemia. No signs of gastrointestinal bleeding were noticed. Colonoscopy was performed, and sigmoid cancer was suspected (a). Biopsies were obtained, which confirmed colonic adenocarcinoma. Eight hours after the endoscopy, the patient developed massive hematochezia, followed by hemodynamic instability (blood pressure 60/30 mm Hg; heart rate 120 bpm; and hemoglobin drop from 9.8 g/dL to 6.1 g/dL within 2 hours). After stabilization with intravenous fluids, norepinephrine, and transfusion of 1 unit of red blood cells, endoscopy was repeated and ruled out ongoing bleeding. A computed tomography scan confirmed a mass of the sigmoid colon, which extended along the inferior mesenteric artery and to the os sacrum. Within the sigmoid wall, extravasation of the contrast medium was seen into a structure of 2.3 × 1.7 cm. Computed tomography reconstructions suspected pseudoaneurysm of the inferior mesenteric artery (Figures B, C). In the absence of distant metastases, surgical resection was attempted urgently. However, owing to infiltration of the aortic wall, curative resection was impossible and colostomy was performed. Angiography confirmed a large pseudoaneurysm of the rectal superior artery, and embolization was performed successfully. The further course was unremarkable.…

