[Malignant lymphomas of the gastrointestinal tract (problems of histogenesis, morphogenesis and histological diagnosis)].

Seventy malignant lymphomas of the gastro-intestinal tract (GIT) (54 lymphosarcomas, 16 lymphogranulomatoses) were studied. GIT lymphosarcomas and lymphogranulomatosis are characterized by the similarity of histogenesis, morphogenesis, and forms of progression. The lymphoid apparatus of GIT is the source of tumor growth, the tumor develops multicentrically and not simultaneously, the progression occurs as autochthonous growth, metastasizing. Isolated GIT lymphomas have a potential trend for generalization. In lymphosarcomas, the predominant histological types are prolymphocytic and lymphoblastic, in lymphogranulomatosis--mixed-cell and lymphocyte exhaustion. Differential diagnosis must distinguish between malignant lymphoma and pseudolymphoma, different variants of lymphomas and low-differentiated carcinoma, which requires examination of the operation material, knowledge of the typical cytological and histological features of lymphoma variants, and the use of the required complex of histological and histochemical methods.