Extranodal marginal zone B cell lymphoma. a. Low magnification shows a germinal center (GC) surrounded by dark cells, which in turn are surrounded by paler cells. b. The paler cells make up the marginal zone and are described as monocytoid cells. c. Other regions consist of small lymphocytes, some with subtle folded nuclear membranes (centrocyte-like cells). d. In other regions, the lymphocytes take on features of plasma cells, so-called plasmacytoid lymphocytes.