[The complex morphologic diagnostic of marginal zone lymphoma.]

The purpose of study: To determine possibilities of complex morphological diagnostic (routine cytology and histology, immunocytochemistry and immunohistochemistry, molecular genetics) of lymphoma of marginal zone. The study included 10 patients with diagnosis of lymphoma of marginal zone cells, established on the basis of application of morphological (cytological and histological), immunomorphologic (immunocytochemical and immunohistochemical) and molecular genetic techniques. The immunofenotyping was implemented using immunocytochemical technique (EnVision FLEX) applying monoclonal antibodies by DAKO manufacturer. The immunofenotyping was implemented by flow cytofluorometry technique (flow cytofluorometer FACS Calibur by Becton Dikinson, USA) using antibodies by DACO manufacturer labeled by fluorescent marks (FITC or RPE). The antibody panel included: common leukocytic antigen, common cytokeratins CD19, CD20, CD79a,CD10, Bcl2, Bcl6, CD23, CD34, TdT, CD3, CD4, CD5, CD8, CyclinD1, Ki67, κ, λ. The FISH technique was applied using probes Bcl2 FISH DNA Probe, Split Signal и MALT1 FISH DNA Probe Split Signal by DAKO manufacturer. In one patient a gene Bcl2 change was detected with purpose of differentiating diagnostic with follicular lymphoma. In three patients, diagnosing lymphoma of marginal zone was implemented by FISH technique using detection of translocation (11;18)(q21;q21), involving gene of inhibitor of apoptosis API2 and gene MALT1. The routine cytological analysis of ten cases permitted to establish an exact diagnosis of lymphoma only in five cases and with no indication that it is lymphoma of marginal zone. In two cases under routine cytological analysis only a suspicion about lymphoma was suggested. In all ten patients a positive expression of pan-B-cellular markers CD19, CD20, CD79a was observed both under immunocytochemistry and immunohistochemistry and flow cytofluorometry. In 6 patients (60%) a positive expression of gene Bcl2 was observed both under immunocytochemistry and immunohistochemistry and flow cytofluorometry. The comparison of immunocytochemistry and immunohistochemistry and flow cytofluorometry established absence of expression of CD5, CD3, CD10, CD34, CD23, Bcl6, TdT, cyclin D1. Under immunocytochemistry and immunohistochemistry in ten cases proliferative activity protein Ki-67made up no more than 30%. Under flow cytofluorometry clonality on light chains of immunoglobulins κ or λ (Igλ/Igκ) were established. Overall, correlation coefficient (r, p < 0,05) between immunocytochemistry and immunohistochemistry, flow cytofluorometry made up to 1. The four patients were applied FISH-reaction for adjustment of diagnosis. In patient with nodal lymphoma of marginal zone gene Bcl2 change was absent. In three patients with MALT-lymphoma a gene MALT1 change was established. Thereby, accuracy of routine cytological analysis at diagnosing lymphoma without indication of its type in case of lymphoma of marginal zone made up to 50%, sensitivity - 50%, specificity - 100%. The accuracy of immunofenotyping permitting diagnosing lymphoma of marginal zone made up to 100%, sensitivity - 100%, specificity - 100%. The correlation coefficient (r, p < 0,05) between data of immunocytochemistry and immunohistochemistry, flow cytofluorometry made up to 1. The accuracy, sensitivity and specificity of complex analysis (cytology, immunocytochemistry and FISH-technique) in diagnostic of lymphoma of marginal zone made up to 100%.