Problems in preoperative typing of malignant gastric tumors

Based on the case report of a 51 year-old patient presenting with a lymphoe pithelioma like gastric cancer, we discuss the diagnostic challenge to diff erentiate this entity from gastric non-Hodgkin lymphoma. Since high-level l ymphoid stromal reactions are rarely associated with gastric adenocarcinoma , misinterpretation can occur easily. In addition to the lymphoepithelioma like gastric cancer that is often associated with a demonstrable EBV associ ation of the tumor cells, synchronous development of gastric carcinoma and lymphoma must be considered. Establishment of a correct diagnosis requires multiple, deep and multifocally sampled gastric biopsies, and immunohistoch emical and molecular techniques to supplement conventional histology. Only through this procedure are correct characterization and classification of t hese unusual gastric neoplasms possible.