Metastatic aortic intimal sarcoma: The use of PET/CT in diagnosing and staging

Abstract

A 67-year-old woman presented with acute cold left foot. Her medical history was remarkable for intermittent bilateral leg pain, abdominal pain, nausea, vomiting, and progressive weight loss. She underwent left superficial femoral artery embolectomy and fasciotomy. Histopathology of the emboli revealed sheets of necrosis with small foci of poorly differentiated malignant neoplasm consistent with intimal sarcoma (*areas of necrosis; black arrows are representative viable tumor cells) (Panel A). Thoracoabdominal CT angiography was performed to determine the source of the tumor emboli. CT angiography revealed a short segment of polypoid mass with amorphic calcifications in the distal descending thoracic aorta wall (Panel B-1, white arrow), focal wall thickening in the infrarenal aortic wall without significant enhancement on the arteriovenous phase, and could not be differentiated from mural thrombus or atherosclerotic plaques (Panel B-2, black arrow). The left renal artery was enlarged and did not enhance, which was suspicious for bland thrombosis and there were several hypodense (white open arrow), non-enhancing liver lesions (*) (Panel B-3). Whole-body fluorodeoxyglucose positron emission tomography (FDG PET) was performed, which showed intense FDG uptake in the thoracic aorta lesion (Panel B-4, white arrow), in the focal wall thickening in the infrarenal aorta (Panel B-5, black arrow), at the left renal artery ostium (Panel B-6, black open arrow) and in the liver lesions (Panel B-6, *). Vascular lesions thought to be multifocal intimal sarcoma or drop metastasis from thoracic aorta primary, and the liver lesions were considered as metastasis. Primary intimal sarcoma is an extremely rare vascular tumor with poor prognosis, and there are fewer than a hundred reported cases in the literature.1–3 In this case, we have demonstrated the clinical value of the FDG PET in the diagnosis and the staging of the intimal sarcoma in addition to CT angiography.