[An electron microscopic study of the effector link in immune reactions in stomach cancer]

21 surgically removed gastric carcinomas of different histologic structure and stage of development were studied ultrastructurally. A variety of morphological manifestations of local immune reactions and nonspecific antitumour resistance were observed. These manifestations were characterized by the contacts of lymphocytes, macrophages, polymorphonuclear leukocytes, plasma cells with each other and with tumour cells and by the presence of variable changes in tumour cells. The causes of such a variety are discussed and they may be due to different types of cytotoxicity, stage of the interaction between the effector and the target and so on.