*4.6.5 Chronic sialdenitis (CS)*

**Chronic sialdenitis (CS)** can also affect minor SGs [53]. It may occur due to repeated episodes of inflammation or secondary to treatment such as radiation therapy for other cancers. Aspirates from CS are hypocellular and shows few clusters of duct cells, fragments of fibrous tissue in background showing lymphocytes. Acinar cells are usually not seen and are absent. The duct cells may undergo metaplastic squamous changes and may show reactive atypia, raising possibility of MEC. In such cases, other features of MEC like mucinous cells and frank epidermoid cells and dirty mucoid background give clues to the diagnosis. Frank atypical features of a carcinomatous cells such as hyperchromatic nuclei and high N:C ratio can be differentiated from reactive changes due to either chronic infection or treatment.

#### *4.6.6 Granulomatous sialadenitis (GS)*

**Granulomatous sialadenitis (GS)** can present clinically as a slow-growing mass that can mimic a neoplasm. Aspirates are usually hypocellular and consist of clusters of epithelioid histiocytes, multinucleated giant cells, lymphocytes and duct cells. Transforming or ill-formed epithelioid cells should not be mistaken for an epithelial neoplasm.

#### *4.6.7 Lymphoepithelial sialadenitis (LESA)*

**Lymphoepithelial sialadenitis (LESA)** primarily affects salivary and lacrimal glands and is also reported in minor SGS [54]. It is believed to be an autoimmune disorder and is associated with sjogrens syndrome and other connective tissue disorders. Aspirate shows lymphoepithelial complex comprising of clusters of cohesive duct cells infiltrated by lymphoid cells. The duct cells may show metaplastic squamous changes or reactive atypia. The background consist of abundant population of large and small lymphoid cells in various stages of maturation, plasma cells and tingible body macrophages. LESA is associated with increased risk of lymphoma particularly extranodal marginal zone lymphoma of MALT type and sometimes it is indistinguishable from it [55]. Ancillary tests such as IHC on cell blocks and immunophenotyping with flow cytometry should be done to distinguish between LESA and lymphoma. Reactive lymphnode can mimic LESA but lymphoepithelial complex is absent. Since LESA can be cystic, other pitfall includes cystic tumours showing background of lymphocytes such as AciCC and low-grade MEC which can be differentiated by presence of their other cytological features.
