[Histocytopathology of monocytoid B-lymphocytic lymphoma]

It is generally accepted, that the cells of non-Hodgkin's lymphomas represent a neoplastic counterpart of corresponding reactive cells. The aim of this study was to compare histocytology of 6 cases of monocytoid B-cell lymphoma (MBCL) with that of reactive monocytoid B-cells of "common" and large cell type. All the lymphomas were diagnosed in peripheral lymph nodes by histology and immunohistochemistry. Histocytological appearance of MBCL corresponded mostly to that of "common typ" MBLy (n=5) with. signs of plasmacytic differentiation (p = 3/5) or rarely (n=1) with increase of intermingled blast cells. Rebiopsy of one of the cases of the "common" cell type showed a progression to a large cell high grade lymphoma of the appearance similar to the large cell type of reactive MBCs. It is therefore to be accepted that the cells of MBCL including its high grade transformation might represent neoplastic counterparts of the reactive MBLy of the "common" and large cell type respectively.