Clinicopathological Study On The Associations Between Ranulas And Autoimmune Diseases

The study aimed to investigate the prevalence of ADs in ranula patients, analyze their clinicopathological features, and explore the associations between ADs and ranulas. This cross-sectional study consecutively enrolled surgically treated ranula patients (2021–2023). ADs diagnosis was established. Clinical, serological and pathological features were compared. Among 102 patients, 36.3% had confirmed ADs (primarily Sjögren's syndrome and undifferentiated connective tissue disease), 42.2% had no ADs, and 21.6% were suspected of ADs. In the confirmed AD group, ranulas preceded AD diagnosis in 83.8% of patients. Compared with the non-AD group, the confirmed AD group had a greater female proportion, an older age distribution, lower salivary secretory function, and positive autoantibodies tests. Histopathological analysis of sublingual glands revealed lymphocytic infiltration, glandular parenchymal destruction, fatty replacement, germinal centers, ductal epithelial destruction, lymphoepithelial lesions, and periductal collagen proliferation in the confirmed AD group, which were also common in the suspected AD group but rare in the non-AD group. The focus score in the confirmed AD group was significantly higher, and the number of mucus extravasation foci was positively correlated with the focus score (r = 0.718, p < 0.01). Grade 3 or 4 lesions (according to the Chisholm & Mason system) and lymphoepithelial lesions were significantly associated with ADs (p = 0.001, p = 0.019, respectively). A considerable proportion of ranulas are associated with ADs, with distinct clinicopathological features. Characteristic pathological changes in the sublingual gland may indicate ADs, which might potentially contribute to ranula development.