Gastric lymphomas: aspects of follow-up and after-care

In recent years, new insights into gastric lymphomas and their etiology and pathogenesis have been gained. The predominant role of infection with Helicobacter pylori in the pathogenesis as a pre-malignant condition of a special lymphoma entity [gastric lymphoma of the mucosa-associated lymphoid tissue (MALT) type], has defined new diagnostic procedures and concepts of treatment. Therefore, prognostic factors (e.g. stage of lymphoma, histopathologic grading, resectability etc.) are extremely important for the intensity and efficacy of follow-up and after-care. Surveillance programs in gastric lymphoma include sequelae of surgical resection, chemotherapy and radiotherapy, and the efficacy of follow-up procedures have to be measured by the prevention of tumor relapse in comparison to the intensity of diagnostic procedures. Since lymphoma relapse may occur both as local or disseminated recurrence in 13%-35% of cases, follow-up procedures have to regard both aspects during surveillance. While these follow-up programs are standardized in epithelial tumors (e.g. colon carcinoma), they are not yet established or comparable for each type of gastric lymphoma. Low-grade MALT lymphomas have to be considered as a new lymphoma entity. In addition, new diagnostic procedures (e.g. molecular parameters such as polymerase chain reaction (PCR) for clonality, endosonography, "gastric mapping") have been found to be important parameters for diagnosis and staging of gastric lymphoma and may therefore be relevant for the course of the disease. The definition of "lymphoma cure" and the impact of these procedures as prognostic factors will have to be discussed and may influence the follow-up of gastric lymphoma.