Chronic Sclerosing Sialadenitis: A Morphologic Diagnosis with Clinicopathologic Correlation
Sarah A Brooks, Mary S Richardson. Medical University of South Carolina, Charleston, SC
Background: Chronic sclerosing sialadenitis is an uncommon cause of salivary gland enlargement with a distinctive morphologic appearance and an increased number of IgG4 plasma cells. We report a case of chronic sclerosing sialadenitis and compare the morphology of chronic sclerosing sialadenitis to other cases of chronic sialadenitis.
Design: 53 cases of chronic sialadenitis were examined and classified into 5 categories: minimal stromal fibrosis; mild stromal fibrosis; moderate to severe stromal fibrosis; chronic sclerosing sialadenitis; and lymphoepithelial sialadenitis. Immunohistochemical staining for IgG and IgG4 was performed on the chronic sclerosing sialadenitis case.
Results: Twelve cases had minimal stromal fibrosis; 22 cases had mild stromal fibrosis; 15 cases had moderate to severe stromal fibrosis; 1 case had chronic sclerosing sialadenitis; and 3 cases were classified as lymphoepithelial sialadenitis. The chronic sclerosing sialadenitis case demonstrated a characteristic intralobular, hypercellular fibrosis with preservation of the lobular architecture and a dense lymphoplasmacytic infiltrate. Immunohistochemical staining for IgG and IgG4 revealed an increased number of IgG4 plasma cells with an increased IgG4:IgG ratio at 0.67.
In comparison, cases of chronic sialadenitis with moderate to severe stromal fibrosis showed paucicellular fibrosis more pronounced around the ducts. Periductal fibrosis was present in all 15 of the cases, but only 8 cases had intralobular fibrosis. Results are summarized in Table 1.
|CS with Minimal Fibrosis (n=12)||CS with Mild Fibrosis (n=22)||CS with Moderate to Severe Fibrosis (n=15)||Chronic Sclerosing Sialadenitis (n=1)||Lymphoepithelial Sialadenitis (n=3)|
|Duct Dilatation||41.6% (5/12)||81.8% (18/22)||86.6% (13/15)||100% (1/1)||66.6% (2/3)|
|Periductal Fibrosis||50.0% (6/12)||90.9% (20/22)||100% (15/15)||100% (1/1)||100% (3/3)|
|Intralobular Fibrosis||0% (0/0)||4.5% (1/22)||53.3% (8/15)||100% (0/0)||0% (0/0)|