Differential characterization of the "reticulum cell" in lymphoreticular
neoplasms. Am J Clin Pathol. 64: 171-179, 1975. The term "reticulum cell" is confusing, having been applied to the cells involved in many
hematopoietic neoplasms, such as
reticulum-cell sarcoma, histiocytic medullary reticulosis,
leukemic reticuloendotheliosis, and monocytic or histiocytic
leukemias. In histologic sections, even the cells from poorly differentiated extramedullary lesions of
chloroma or myeloblastic
leukemia have been called "reticulum cells."A combined morphologic and cytochemical approach has been used to study "reticulum cells"in smears and tissue sections of
neoplasms involving "histiocytes" or "reticulum cells."The cytochemical markers are: chloracetate
esterase for neutrophilic granulocytes;
nonspecific esterase and
fluoride-resistant
esterase for monocytes and histiocytes (phagocytes);
tartrate-resistant acid phosphatase for the reticulum cells of
leukemic reticuloendotheliosis; pyronin for the lymphatic reticulum cells (germinal center cells). The morphology of these cells is very well appreciated in smears, and the locations of these marked cells in tissue sections are easily recognized. The use of cytochemical and immunochemical methods and functional studies, in addition to simple morphology, may be useful in subclassification of lymphoreticular
neoplasms.