Low-Grade Primary Mucosa-Associated Lymphoid Tissue Lymphoma of the Nasopharynx: Clinicopathological Study

Background Malignant tumors of the nasopharynx are always a challenging problem, both from the diagnostic and from the therapeutic standpoint. Most extranodal lymphomas arise in the gastrointestinal tract, but the other mucosal organs also may be involved, especially the upper aerodigestive tract. Nasopharyngeal lymphomas are rare among lymphoma of the upper aerodigestive tract. Methods Twenty-two patients with primary lymphoma arising in mucosa-associated lymphoid tissue of the nasopharynx have been studied with reference to age, sex, clinical symptoms, laboratory finding, radiological finding, histological subtype, and immunohistochemistry. Results All patients were diagnosed histologically as low-grade lymphoma of mucosa-associated lymphoid tissue type with its characteristic lymphoepithelial lesions and follicular colonization. The tumor cells typically exhibit the following immunophenotypes: positive for CD20, CD45RA, and proliferating markers bcl-2. It was negative for T-cell markers CD45RO (UCHLI). Conclusion Ear, nose, and throat surgeons and pathologists should be aware of this type of lymphoma to avoid misinterpretation and to set up a protocol for its management.