Mediastinal IgG4-Related Disease Manifesting as Superior Vena Cava Syndrome.

ABSTRACT

Immunoglobulin G4 (IgG4)-related disease was first identified as a systemic condition in 2003 when extrapancreatic manifestations were identified in patients with autoimmune pancreatitis. Its peak incidence occurs in the fifth or sixth decades of life. Isolated extraaortic mediastinal involvement is extremely rare. This report describes a case of isolated extraaortic mediastinal IgG4-related disease encasing the superior vena cava (SVC) and manifesting as SVC syndrome in a 25-year-old man with no personal or family history of autoimmune disease. Resection with SVC reconstruction was performed.