Küttner tumour and IgG4-associated sialadenitis as a benign cause of swelling of the submandibular glands

This is a case report of a 53-year-old man who had a swelling of both submandibular glands and an elevated serum immunoglobulin G (IgG) level. The histopathology examination was positive for IgG4 plasma cells with an IgG4/IgG ratio of 0.62, which is diagnostic for IgG4-associated sialadenitis.If IgG4-associated sialadenitis is suspected fine needle aspiration, serum IgG/IgG4 and examination of extra salivary disease should be performed to confirm the diagnosis.