Gastric pseudolymphoma. Its three subtypes and relation to lymphoma.

Three separate histologic types of gastric pseudolymphoma (GPL) are described: (1) the common "inflammatory" type usually accompanied by ulceration and extensive fibrosis; (2) the entity known as "nodular lymphoid hyperplasia," which was associated with multiple intestinal lesions; and (3) the third reported case of angiofollicular lymphoid hyperplasia of the stomach (one with nodal involvement). Criteria for the common type were developed and, in general, confirm previous studies. However, the importance of evaluating nuclear cytology and mitotic rate are stressed. Organ infiltration by chronic lymphocytic leukemia should be excluded by the absence of an absolute peripheral lymphocytosis. In addition to the ten cases presented, the literature on 175 previous cases is summarized. GPL is estimated to account for 10-15% of all gastric lymphoid tumors. In comparison to gastric lymphoma, GPL is usually smaller in size and occurs a decade earlier on the average. Since an associated focal lymphoma was documented in an additional five cases, this study proposes that pseudolymphoma be considered a precursor lesion with malignant potential. Extensive pathologic sampling and total surgical excision are recommended.