Abstracto

The changing sands of diagnosis in hematopathology: Anaplastic massive cell lymphoma.

Hofman James

The paradigm for defining new disease entities, Anaplastic Large Cell Lymphoma (ALCL), offers a model that can be used in many fields of pathology. Characteristic histologic characteristics and a specific immuno-phenotype were used to diagnose ALCL for the first time. Sinusoidal invasion and CD30 positivity, however, did not show to be completely specific. Following the discovery of a distinctive cytogenetic aberration, the genes responsible for the translocation were discovered, providing new information about the pathophysiology. The production of monoclonal antibodies to anaplastic large cell lymphoma kinases with aberrant expression, such as ALK-1, can be employed for diagnostic purposes and has enhanced characterization of the diagnostic entity with significant clinical and prognosis implications. The connection between ALCL and Hodgkin's disease, a different lymphoid cancer connected to CD30 expression. We now know that the true histologic range of ALCL is both narrower and wider than previously thought. Although the neoplastic cells may not appear big or anaplastic, the small cell and lymph histiocytic types of ALCL are recognised as being ALK-positive and part of the disease entity. On the other hand, the majority of cases of Hodgkin's-like ALCL have shown to be unconnected to ALCL and more closely related to the actual Hodgkin's disease.