Lymphoma

LYMPHOMA (otherwise lymphadenoma or lymphocytoma), a name long assigned to foci of new growth of lymphoid tissue, arising either in the lymph glands themselves or outside them. Such neoplasms are occasionally encountered in reality (so-called lymphocytomas), arising, for example, in the bone marrow, salivary and thyroid glands, etc. Sometimes they consist not of lymphocytes, but of plasma cells (plasmacytoma). The nature of these neoplasms is obscure; most often they do not belong to true tumors and arise either on the basis of chronic inflammation, as a product of "organized" inflammation, or in systemic diseases of the hematopoietic apparatus, specifically in leukemic and aleukemic lymphadenoses. Small foci of lymphoma, the size of a pinhead, are localized in this case most often in the liver, less often in the kidneys, bone marrow, and other organs; they are constructed of a delicate reticular network (well demonstrated by silver staining) and lymphoid cells embedded within it. In the liver, such lymphomas nest in Glisson's capsule, forming rather sharply demarcated foci, very characteristic of lymphadenoses. In the kidneys, lymphomas have a more diffuse character and are formed more often in the cortical layer, where they push apart the convoluted tubules. By analogy with these lymphomas, the same name is used to designate foci of hematopoiesis in myeloses, although they consist not of lymphoid elements, but of myeloblasts or granulocytes and form not demarcated nodules, but diffuse infiltrates, for example, in the liver, where they spread along the intralobular capillaries. It is also incorrect to call those accumulations of mononuclear cells of the epithelioid type, which form in solitary follicles, Peyer's patches of the intestines, in mesenteric and other lymph glands, in the liver and spleen during typhoid fever and paratyphoid fevers, especially in paratyphoid N, lymphomas. These foci originate through hyperplasia of reticular cells (reticulo-endothelium), and not lymphocytes. It is more correct to classify them as specific granulomas. The term "lymphoma malignum," which has fallen out of use at the present time, usually referred to what is now known by the name of lymphogranulomatosis (see), less often to lymphosarcoma (see). It is completely erroneous to call swellings of the lymph glands arising on the basis of inflammatory processes or intoxications lymphomas or lymphadenomas.