Pseudolymphoma of the stomach. A diagnostic and therapeutic dilemma.

Pseudolymphoma is an uncommon benign lesion of the stomach that poses a difficult problem in diagnosis and management. The clinical manifestations and endoscopic, radiologic, and biopsy findings are not generally helpful in making this diagnosis preoperatively. Histologic examination of the lesion is the only reliable method that distinguishes pseudolymphoma from true lymphoma. Distinguishing histologic features of pseudolymphomas are (1) formation of true germinal centers, (2) presence of a polymorphous inflammatory infiltrate, and (3) absence of lymph nodal involvement by lymphoma. We report four cases and review the literature to illustrate the features of pseudolymphoma. Subtotal gastric resection is done for diagnostic as well as for therapeutic purposes. Distinction of these benign lesions from malignant lymphomas is important so that unnecessary radical surgery and postoperative radiation therapy or chemotherapy are avoided.