ABSTRACT
Immunoglobulin G4-related sclerosing disease (IgG4-RD) is histologically a chronic inflammatory disorder characterized by infiltration of lymphoplasmacytes, sclerosis, and an elevated serum level of IgG4 and IgG4 positive plasmocytes. IgG4-RD is associated with autoimmune pancreatitis, sclerosing cholangitis, sialalithiasis, retroperitoneal diseases, inflammatory arotitis and Mikulicz's disease, typically including the lacrimal glands, salivary glands, pancreas, thyroid gland, lungs and kidneys. It is important to distinguish IgG4-RD from neoplastic disease as it responses well to steroid. Because consensus for nomenclature of IgG4-RD is recently made, reports of IgG4-RD in the Head and Neck area are still rare. In the first case, a 68-year-old man presented with a recurring submandibular gland mass from 7 years ago; he underwent submandibular gland resection and was diagnosed as IgG4-RD. In the second case, a 69-year-old mass presented with a relapsing right neck mass on level Ib. He underwent an exsional biopsy and was diagnosed with the same disease entity. We experienced two cases of IgG4-RD, and so report them with a brief literature review.