Küttner's tumor of the submandibular glands: report of five cases with fine-needle aspiration cytology.

Küttner's tumor (KT) is a benign tumor-like lesion of the salivary gland that mimics neoplasm clinically because of presentation as a hard mass. Recently, the histomorphological and immunohistochemical findings of this lesion have been analyzed, and differential diagnostic problems relating to salivary gland lymphoma have been discussed. However, currently there is little information on the cytological findings of those lesions. We present cytological findings from five such cases using fine-needle aspiration cytology (FNAC). FNAC of this lesion may present a diagnostic challenge to the cytologist as lesions share some cytologic features with inflammatory process containing numerous lymphoid cells. Smears obtained from two cases contained moderate to large numbers of lymphoid cells without definite cytological atypia, scattered ductal structures, and acinar cell clusters. The remaining three cases showed low cellularity probably attributable to fibrosis that made it difficult to aspirate the cellular element. FNAC findings of scattered ductal structures surrounded by collagens and infiltrated by a mixed population of lymphoid cells, not specific for KT, are highly suggestive of the diagnosis with the appropriate clinical findings. However, a portion of cytological specimens of KT containing relatively large numbers of lymphoid cells should be differentiated from malignant lymphoma arising from the submandibular gland.