Primary Leiomyosarcoma of the Superior Vena Cava: A Rare Case Report.

Leiomyosarcoma of the superior vena cava (SVC) is an exceptionally rare vascular tumor. Fewer than 20 cases were reported worldwide. Because of the nonspecific nature of the presenting symptoms and their deep mediastinal location, a pre-operative diagnosis is often difficult or impossible. A 63-year-old woman presented with progressive facial and upper-limb edema. Computed tomography (CT) demonstrated a hyper vascular intraluminal mass originating in the SVC and extending towards the right atrium. Percutaneous biopsy was considered unsafe due to the risk of hemorrhage. Therefore, radical surgical resection of the SVC and brachiocephalic veins with xenopericardial patch reconstruction was performed. Histological and immunohistochemical examination confirmed a grade two leiomyosarcoma. No adjuvant therapy was given. At 8-month follow-up, there was no evidence of recurrence. Primary SVC leiomyosarcoma is a rare and diagnostically challenging condition. Pre-operative biopsy is often not feasible, and radical en bloc resection with vascular reconstruction remains the cornerstone of treatment, offering the best chance of recurrence-free survival. Histopathological confirmation is required to establish the diagnosis, and the role of adjuvant therapy remains uncertain.