Balanced double aortic arch with late-onset symptoms detected on 18F-FDG PET/CT in an octogenarian with advanced prostate cancer

RATIONALE: Double aortic arch (DAA) is a rare congenital vascular anomaly usually diagnosed in infancy. Adult or elderly presentation is uncommon, and balanced-type DAA is relatively rare. On oncologic 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT), a mediastinal tubular structure with blood-pool-level FDG uptake may provide an important clue to a vascular anomaly. PATIENT CONCERNS: An 80-year-old man with biopsy-proven advanced prostate cancer underwent 18F-FDG PET/CT for systemic staging. He had dysuria and back pain for more than 1 year, with mild intermittent swallowing discomfort. DIAGNOSES: PET/CT showed multiple FDG-avid bone metastases. Axial and coronal PET/CT images demonstrated bilateral aortic arch components adjacent to the tracheoesophageal region, with FDG uptake equivalent to the aortic blood pool. Three-dimensional volume rendering confirmed balanced-type DAA forming a complete vascular ring. INTERVENTIONS: No DAA-directed intervention was performed. Additional CT angiography was not pursued because the PET/CT findings were characteristic and further vascular imaging was unlikely to alter management. OUTCOMES: Conservative management was recommended. At approximately 6 months after PET/CT, the patient's intermittent swallowing discomfort remained stable, and no DAA-directed intervention was performed. LESSONS: Balanced-type DAA may be incidentally detected on oncologic 18F-FDG PET/CT. Recognition of a tubular mediastinal structure continuous with the aortic system and showing blood-pool-level FDG uptake may help avoid misinterpretation as malignant mediastinal disease.