Nodular lymphoid hyperplasia of the stomach in a patient with multiple submucosal tumors

Nodular lymphoid hyperplasia of the stomach is a rare lymphoproliferative disorder. Here, we report a 38-year-old man who presented with multiple submucosal tumors of the stomach. Histologically, the lesions were characterized by multiple discrete submucosal nodules of lymphoid cells. The infiltrates between the lymphoid follicles were composed mainly of medium-sized lymphoid cells with abundant clear cytoplasm, as well as a few large cells with vesicular nuclei. The gastric mucosa exhibited multifocal lymphoid aggregates and some of the epithelial cells were infiltrated by small lymphocytes mimicking lymphoepithelial lesions. Histopathology was consistent with mucosa-associated lymphoid tissue lymphoma. However, the infiltrating lymphoid cells were positive for CD2, CD3, CD5, and CD7. In addition, polymerase chain reaction analysis of the immunoglobulin heavy chain and T-cell receptor gene rearrangements demonstrated polyclonality. This case was diagnosed as reactive lymphoid hyperplasia of the stomach.