Morphometric characterization of diffuse large-cell (histiocytic) lymphomas.

From 28 large-cell lymphomas, defined by marker studies, enzyme histochemistry, and electron microscopy as large noncleaved follicle center cell tumors (lnc FCC), B-immunoblastic or true histiocytic lymphomas, morphometric cell parameters, including nuclear size and shape, cytoplasmic area, and cytoplasm-to-nucleus ratio, were measured. Moreover, size, number, and location of nucleoli in the nuclei of the characteristic cells of lnc FCC and B-immunoblastic lymphoma were determined. Statistical evaluation of the data showed the nuclear shape to be the most sensitive parameter in the differentiation of true histiocytic lymphoma from lnc FCC and B-immunoblastic lymphomas. With nucleolar parameters lnc FCC could be differentiated from B-immunoblastic lymphoma: lnc FCC had a higher mean number of nucleoli per cross-section of nucleus and more eccentrically located nucleoli. Moreover, the measurements show that the differences in number and location of nucleoli between large noncleaved follicle center cells and B-immunoblasts are smaller than generally described in the literature. Our results show that it is possible to differentiate by morphometry between lnc FCC, B-immunoblastic, and true histiocytic lymphomas.