Non sebaceous lymphadenoma of the parotid gland: Two-case report

Abstract

Many different tumors, both cystic and/or solid, arising in the salivary glands are associated with a prominent lymphoid stroma. Lymphadenoma without sebaceous differentiation is an exceedingly rare benign tumor of salivary glands, included since 2005 in the WHO classification of salivary gland tumors. Until now only few cases of this entity have been reported in the English literature.We herein report the clinico-pathological characteristics of two cases of this rare tumor, arising in the parotid gland and affecting two middle-aged women. Both tumors were delimited by a fibrous capsule from the surrounding normal gland, and composed microscopically by abundant lymphoid stroma with florid follicular hyperplasia admixed with epithelial cuboidal and cylindric bland cells that express inmunohistochemical luminal fenotype with cytokeratins. The cells do not have sebaceous and/or oncocytic differentiation. At the present moment both patients are disease free, without local recurrence and/or metastasis, 26 and 10 months after initial diagnosis.Lymphadenoma is a rare benign neoplasm of salivary glands. In the last years more cases are being published in literature that will contribute to recognize and understand the development of these benign or hamartomatous tumor. The complete surgical excision of the mass has been curative in all cases and the absence of recurrence and/or metastatic disease supports it benign nature.