Immunoglobulin G4 (IgG4)-related disease is a newly named fibroinflammatory condition characterized by tumefactive lesions that contain dense lymphoplasmacytic infiltrates rich in IgG4-positive cells. Elevated serum IgG4 concentrations also often accompany IgG4-related disease. Many medical conditions that were long viewed as diseases confined to single organs (e.g., Mikulicz disease, type 1 autoimmune pancreatitis, Riedel’s thyroiditis, multifocal fibrosclerosis, inflammatory pseudotumor, mediastinal fibrosis, retroperitoneal fibrosis, and etc.) are now designated as part of the spectrum of IgG4-related disease. The preferred nomenclature suggested by a committee of international experts uses the prefix “IgG4-related-” for individual organ involvement, regardless of the organ system affected. One exception is type 1 autoimmune pancreatitis (IgG4-related pancreatitis). Comprehensive diagnostic criteria for IgG4-related disease and organ-specific diagnostic criteria (e.g., IgG4- related dacryoadenitis and sialadenitis, type 1 autoimmune pancreatitis, IgG4-related kidney disease and IgG4-related sclerosing cholangitis) can aid clinicians in the diagnosis of this erratic condition.

자가면역췌장염과 췌장암의 감별진단은 유사한 임상증상 들과 영상검사소견을 보일 수 있기 때문에 종종 어렵다. 혈청 IgG4는 자가면역췌장염과 췌장암의 감별에 중요한 인자 이다. 췌장암 환자에서도 약 10%에서는 혈청 IgG4가 상승할 수 있으나, 대부분 정상 상한의 2배 이내이다. 그래서 저자들은 자가면역췌장염과 감별이 어려웠던 혈청 IgG4가 정상 상 한의 6배 이상으로 상승된 췌장암 1예를 경험하였기에 문헌 고찰과 함께 보고하는 바이다.