IgG4-Positive Plasma Cell Infiltrates in Chronic Sialadenitis Involving Submandibular Glands
SS Shah, TC Smyrk, JE Lewis. Mayo Clinic, Rochester, MN
Background: Chronic sclerosing sialadenitis (CSS) is a chronic inflammatory disorder of salivary glands which most commonly affects submandibular glands. CSS has been postulated to be an IgG4-related disease with occasional cases associated with systemic manifestations. The aim of our study was to assess the frequency of increased IgG4-positive plasma cells in chronic sialadenitis involving submandibular glands, and study the possible clinical associations with other IgG4-related diseases.
Design: We studied 81 consecutive excised submandibular glands with chronic sialadenitis and no associated head and neck malignancy. Surgery was performed from 1992-2008, and follow-up ranged from 1 day to 154 months (mean 52 months). IgG4-positive plasma cells were averaged in three high power fields (hpf) and graded as negative (<5/hpf), mild (6-10/hpf), moderate (11-30/hpf) and marked (>30/hpf). Results of IgG4 stain were correlated with clinical features (age, gender, presentation, presence of IgG4-related disease, IgG4 and autoantibody levels) and histologic findings (degree of lymphoplasmacytic infiltration, fibrosis, lymphoepithelial lesions, lymphoid follicle formation and phlebitis).
Results: 27 cases (33%; M:F=5:4) showed marked (18 cases) or moderate (9 cases) increase in IgG4-positive plasma cells and were classified as IgG4-positive. These cases showed mild to marked lymphoplasmacytic infiltrate with plasma cells comprising 10% to 80% of the infiltrate. IgG4-positive cases showed increased fibrosis (100% vs. 78%, p=0.007), lymphoepithelial lesions (59% vs. 19%, p=0.0004) and association with sialolithiasis (59% vs. 24%, p= 0.003) compared to remaining cases. There was no significant difference in lymphoid follicle formation (48% vs. 32%, p=0.15) or phlebitis (0% vs. 4%, p=0.5) between the two groups. Of the 27 IgG4-positive cases, 21 (78%) presented with mass and 1 (4%) had associated lymphadenopathy. IgG4 and ANA levels were performed only in one case each and were normal. Associated IgG4-related diseases were identified in 4 cases (15%) including 2 cases with cholangitis, 1 case with orbital pseudolymphoma and 1 case with retroperitoneal fibrosis. At last follow up the patients were alive and well (23 cases) or had died of unrelated disease (4 cases).
Conclusions: Nearly a third of cases of chronic sialadenitis affecting the submandibular glands showed increased IgG4-positive plasma cell infiltrates. IgG4-positive cases had increased incidence of fibrosis, lymphoepithelial lesions and association with stones. The majority of patients did not have other IgG4-related diseases.
Category: Head & Neck
Monday, March 22, 2010 9:30 AM
Poster Session I Stowell-Orbison/Surgical Pathology/Autopsy Awards Poster Session # 171, Monday Morning