[Monocytoid B-lymphocyte lymphoma: a new type within the spectrum of non-Hodgkin's B-cell lymphoma].
BACKGROUND
Clonal proliferation of monocytoid B-lymphocytes (MBLy)--monocytoid B-cell lymphoma (MBCL) represents a "new" type of lymphoma within the spectrum of B-cell malignancies.


OBJECTIVE
The aim of the study was to evaluate the possibilities of a routine histological and immunohistochemical diagnosis of MBCL.


METHODS
Three cases of MBCL diagnosed in peripheral lymph nodes (n = 2) and in mammary gland with infiltration of regional lymph node (n = 1) were analyzed both histologically and immunohistochemically using a panel approach (Ig chains, CD30 antigen, markers of B-cells, T-cells and of monocytes/histiocytes).


RESULTS
Morphological appearance of neoplastic cells of MBCL is identical to that of MBLy in reactive conditions--kidney-shaped nuclei, bright clear PAS-negative cytoplasm, and small inconspicuous nucleoli.


CONCLUSIONS
Morphological appearance together with immunophenotypic results (positivity of CD20 and Ki-B5, negativity of CD3, CD43, CD45RO, and of lysozyme, negativity of CD30) are considered to represent sufficient diagnostic criteria of MBCL, including its differential diagnosis of other B-cell low grade malignancies. An increase of large cell type MBLy might represent a feature of a secondary blastic transformation of MBCL. (Tab. 2, Fig. 5, Ref. 27.)
Plank
L
L
Institute of Pathology, Jessenius School of Medicine, Comenius University, Martin, Slovakia.
Sokol
L
L
Adamkov
M
M
Szépe
P
P
Pokorná
E
E
Strachilová
J
J
Ocková
J
J
Sekerková
S
S
Balková
R
R
D000368:Aged; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D016393:Lymphoma, B-Cell / Q000737:chemistry / Q000145:classification / Q000473:pathology; D008297:Male; D008875:Middle Aged