Evaluation of submandibular versus labial salivary gland fibrosis in IgG4-related disease.

The newly comprehensive diagnostic criteria in 2011 emphasize the importance of IgG4-positive plasmacyte infiltration along with storiform or swirling fibrosis and obliterative phlebitis in diagnosing IgG4-related disease(RD). Although labial salivary gland (LSG) biopsy is a minimally invasive and convenient procedure for obtaining tissues, LSG fibrosis is thought to be inconspicuous or absent in IgG4-RD cases. In this study we evaluated 15 patients with IgG4-RD, in whom both submandibular gland (SMG) and LSG biopsies were performed at the same time. Histological evaluation revealed fibrosis in all the SMG specimens but in only one LSG specimen (6.7%). The diagnosis of IgG4-RD is primarily based on its morphological appearance on biopsy. The results of this study demonstrated that although more invasive than LSG biopsy, SMG biopsy is recommended for accurate diagnosis of IgG4-related MD and to exclude malignant diseases.