Non-Hodgkin Lymphomas

Abstract

THE TERM "non-Hodgkin lymphomas" is applied to a group of diverse neoplasms that arise in the reticuloendothelial system. Brief summaries of two commonly encountered types of non-Hodgkin lymphoma—diffuse histiocytic lymphoma and nodular, lymphocytic, poorly differentiated lymphoma (Rappaport et al¹classification)—illustrate some of the variability of features and natural history between types. Diffuse histiocytic lymphoma, which accounts for approximately 30% of all non-Hodgkin lymphomas, is associated with a generally poor prognosis (median survival, about one year). It occurs more frequently in men than in women, but in both sexes there is a broad age distribution. Severe impairment of cell-mediated immunity, constitutional symptoms (fever, night sweats, and weight loss), and intra-abdominal involvement at the time of initial presentation are common. Diffuse histiocytic lymphoma is more likely to involve tissue in the Waldeyer tonsillar ring, the gastrointestinal tract, or other extranodal sites, but one third of these lymphomas are quite localized initially and