Extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue-type in the lower labial minor salivary gland of a patient with Sjögren's syndrome

Patients with autoimmune and chronic inflammatory conditions are at increased risk of developing lymphoma. We report a case of extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) in a 60-year-old woman who has been treated for Sjogren's syndrome for the last 8 years. She was referred to our hospital because of a painless swelling in her left lower lip. There were no clinical signs of major salivary gland swelling or systemic lymphadenopathy. The tumor was removed surgically, and microscopic examination showed it to be characterized by lymphoepithelial lesions, proliferation of centrocyte-like cells, and follicular colonization, leading to the diagnosis of MALT lymphoma. The patient has undergone periodic systemic examination without evidence of tumor recurrence for 18 months since the surgical treatment. The present report supports the postulation that the labial salivary gland biopsy can offer early diagnostic clues to lymphoma development in patients with underlying Sjogren's syndrome.