Diagnostic utility of submandibular and labial salivary gland biopsy in IgG4-related sialadenitis.

Objective: The diagnostic utility of labial salivary gland (LSG) biopsy for IgG4-related sialadenitis remains undetermined. The purpose of the present study was to determine whether submandibular gland biopsy could be replaced by LSG biopsy for diagnosing IgG4-RS. Patients and methods: Medical records of two groups of patients were reviewed. Group A contained 45 patients suspected to have IgG4-RS who underwent both SMG and LSG biopsies. Group B contained 25 patients who were clinically and pathologically diagnosed with Sjögren syndrome (SS). Biopsy samples were stained using hematoxylin and eosin (HE) and immunohistochemical techniques and observed under an optical microscope. Relevant data describing histopathological characteristics were collected and analyzed. Results: SMG of IgG4-RS patients presented typical histopathological characteristics of fibrosis and IgG4-positive plasmacytic infiltration, while LSG showed varied characteristics. The sensitivity and accuracy of SMG for diagnosing IgG4-RS were greater than those of LSG (100% and 100% versus 55.3% and 75.7%, respectively, P < 0.05). Conclusions: Biopsy of SMG showed greater sensitivity and specificity, whereas LSG biopsy showed varied histopathological and immunohistochemical characteristics; thus, SMG biopsy cannot be replaced by LSG biopsy for diagnosis of IgG4-RS. Key Point • Biopsy of SMG showed greater sensitivity and specificity than LSG biopsy for diagnosis of IgG4-RS. [ABSTRACT FROM AUTHOR]