Warthin's tumor associated with IgG4-related disease

Immunoglobulin G4-related disease (IgG4-RD) is an inflammatory condition associated with elevated serum IgG4 levels and tissue infiltration by IgG4-expressing plasma cells. Several inflammatory conditions associated with IgG4-RD have been reported. Warthin's tumor is a benign parotid gland tumor consisting of oncocytic epithelial cells and lymphoid stroma containing lymphoid follicles with reactive germinal centers. This is the first report describing a case of Warthin's tumor with possible involvement of IgG4-RD. The patient was a 71-year-old man presenting with swollen right parotid and bilateral submandibular glands. He had a history of a Warthin's tumor of the left parotid gland, autoimmune pancreatitis, and an inflammatory abdominal aortic aneurysm. Laboratory tests revealed a high serum IgG4 level. Histological examination of the resected parotid gland showed a Warthin's tumor and a nodule showing severe lymphocytic infiltration containing many IgG4-positive plasma cells. This case shows the possible involvement of Warthin's tumor with IgG4-RD.