The Principles of Lymphocyte Development and Lymphocyte Trafficking Support the Diagnosis of Lymphoma

摘要

A diagnosis of lymphoma is currently made on the basis of clinical, histologic, and immunophenotypic criteria. Histologic evidence of lymphoma includes the presence of dense cellular infiltration, a monomorphic appearance of infiltrating lymphocytes,cytological immaturity of the lymphoid infiltrate, and disruption, effacement, and replacement of the normal structures of the involved tissue by infiltrating cells. Immunophenotypic assessment is a useful aid in lymphoma diagnosis, and it may increase the index of suspicion of lymphoma when the majority of cells express the same phenotype. Difficulties arise when lymphomas arise in sites of chronic inflammation, especially in skin and gut. In these instances, it may be difficult to identify lymphoma in a background of inflammatory infiltration. Molecular clonality assessment is used to demonstrate clonal expansion of lymphocytes consistent with lymphoma in these instances.