Composite Epstein-Barr virus-positive mucosa-associated lymphoid tissue lymphoma and Epstein-Barr virus-negative diffuse large B-cell lymphoma in the parotid salivary gland of a patient with Sjögren’s syndrome and rheumatoid arthritis: a case report

摘要

Parotid salivary gland.  Acinar atrophy due to diffuse infiltration of two distinct cell populations. Large lymphocytes are seen in left portion of the image, and the epithelial structures of the salivary gland with infiltration of small lymphocytes are seen in the right portion. H&E stain, 100× magnification. The area of the parotid salivary gland affected by mucosa-associated lymphoid tissue (MALT) lymphoma. Small lymphocytes with round or centrocyte-like nuclei with moderately dispersed chromatin and inconspicuous nucleoli are seen. H&E stain, 400× magnification. The area of the parotid salivary gland affected by MALT lymphoma. Epstein-Barr virus (EBV)-positive lymphocytes. EBV-encoded small ribonucleic acids (EBERs) detected by hybridization (ISH), 100× magnification. Area of the parotid salivary gland affected by diffuse large B-cell lymphoma (DLBCL). Large lymphocytes with oval to round and irregular nuclei with prominent nucleoli, with a moderate amount of cytoplasm. H&E stain, 400× magnification. Area of the parotid salivary gland affected by DLBCL. EBV-negative large lymphocytes. EBERs detected by ISH, 400× magnification