Flow Cytometry, Cytogenetics and Molecular Genetics -- Lymphocytosis


FLOW CYTOMETRY:

Flow cytometric immunophenotypic studies performed on bone marrow demonstrate CD5 positive, CD10 negative, CD23 negative, FMC7 positive, kappa monoclonal B-lymphoid cells. Surface immunoglobulin expression is intermediate. CD20 staining is bright. Admixed are fewer heterogeneous T-cells and maturing myeloid cells with less than 1% CD34 positive blasts.

CYTOGENETICS:

73-80,XXX,-Y,trp(1)(p31.2p32.3)x2,t(1;7)(p13;q32)x2,del(4)(p14),+8,add(9)(p13),-9, t(11;14)(q13;q32)x2, add(12)(p11.2)x2,add(13)(q32),-13,-14x2,-17x2,-22x2,+mar[Cp14] /46,XY[4]

Mosaic abnormal male bone marrow chromosome analysis with an apparently normal cell line and one that appears to have a hypotetraploid chromosome pattern with multiple consistent chromosome rearrangements. These include loss of the Y chromosome; two copies of an abnormal chromosome 1 with a triplication of a segment in the short arm; two copies of a translocation between the proximal short arm of chromosome 1 and the distal long arm of chromosome 7; a deletion of the short arm of one chromosome 4 in several cells; an abnormal chromosome 9 with an additional chromatin segment attached to the proximal short arm; loss of one chromosome 9; two copies of a translocation between the long arms of chromosome 11 and 14; two copies of an abnormal chromosome 12 with a large chromatin segment attached to the proximal short arm; an abnormal chromosome 13 with an additional chromatin segment attached to the distal long arm; loss of one chromosome 13; disomies 14, 17, and 22; and gain of an unrecognized marker chromosome.

The translocation, t(11;14)(q13;q32), which is found in two copies in this study, is compatible with bone marrow involvement by mantle cell lymphoma. As a result of this translocation, the PRAD-1/CCND1 gene at band 11q13 is juxtaposed to an IgH-enhancer sequence at band 14q32. Polyploidy and the abundance of structural chromosome abnormalities in addition to the 11;14 translocation indicate disease progression with clonal evolution and suggest a poor prognosis.

MOLECULAR GENETICS:

t(11;14) (bcl-1/JH, Major translocation cluster) translocation is not detected.

Analytic sensitivity of this assay was about 1 in 1,000 marrow cells. Since only about 50% of mantle cell lymphomas are characterized by this type of translocation, this negative result cannot confirm or exclude a diagnosis of mantle cell lymphoma

FINAL DIAGNOSIS




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