Sjögren's syndrome (SS) is an autoimmune disorder in which lymphocytes infiltrate the exocrine glands, resulting in the development of sicca symptoms. Lymphocytes may also invade various other organs and cause diverse symptoms. Interstitial pneumonia has been observed frequently in SS patients...

Primary retroperitoneal mucinous cystadenocarcinoma is a rare tumor. Only about 30 such cases have been reported in the worldwide literature, and a few Korean cases have been reported. The pathogenesis is not clear, and coelomic metaplasia of the retroperitoneal mesothelium has gained wide suppor..