Patients with gastric cancer undergoing surgery have much to endure and are accompanied by many risks. These risks depend on localization and extent of the tumor, the patients' general condition (nutritional and immune status), age, coexistent diseases and the extent of the required operation. In view of these facts, the principle of radical surgery must be weighed against the tolerance capability of the patient, especially in old people. Extensive diagnostic procedures are necessary to explore those risks. The preoperative treatment (hyperalimentation), the well considered indication for surgery, the choice of operation with lowest risk and the perioperative measurements are of great importance in limiting the risk for the patient.