The Monotonous Small-Cell Pattern.

Small lymphocytes measure <12 μm in diameter, equivalent to the size of a histiocyte nucleus, a segmented neutrophil, or 1.5 to 2 times the size of an erythrocyte. The presence of a monotonous proliferation of small lymphoid cells in an enlarged round and rubbery lymph node is abnormal, and the cytologic findings should be correlated with the clinical scenario. Chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) and the resolving or quiescent phase of a reactive lymphoid hyperplasia are the main and most common entities considered in the differential diagnosis and must be distinguished from other neoplastic and non-neoplastic processes. The following is a list of entities showing the monotonous small-cell pattern. The cytologic description is based on Romanovsky-stained, air-dried smears. We use the WHO classification and nomenclature for lymphoid neoplasms unless otherwise is noted. [ABSTRACT FROM AUTHOR]