Extranodal Lymphoproliferative Processes

摘要

The diagnosis of primitive extranodal (EN) non-Hodgkin lymphoma (NHL), as well as their classification and proper treatment, are a common challenge in the routine assessment of lymphoproliferative processes. The term "primitive" is used to distinguish EN-NHL from secondary involvements of EN sites by nodal NHL [1]. EN-NHL may display a variety of morphological features, molecular alterations, and clinical presentations. They can arise in different usual or unusual sites, including the salivary glands (SG) and oral cavity, lung and upper respiratory tract, thyroid, breast, gastrointestinal tract, bone and soft tissues, orbit, and central nervous system [1]. The organ of EN-NHL onset, other than the specific entities, is important for the natural history and prognosis of the disease. EN-NHL is often related to different aetiologies and molecular mechanisms, and may be indolent or aggressive; the corresponding organ of onset shows distinct histopathological features, requires specific staging, follows specific patterns of dissemination and relapse, and requires different treatments [2].