Distribution of the cytogenetic abnormality +i(3)(q10) in persistent polyclonal B‐cell lymphocytosis: a FICTION study in three cases

Abstract

Persistent polyclonal B‐cell lymphocytosis (PPBL) is a rare entity characterized by a moderate but sustained lymphocytosis where some binucleated or bilobulated circulating forms constitute, even if they are not entirely specific, the cytological hallmark of the disease. An additional chromosome long arm i(3)(q10) has recently been reported as a recurrent cytogenetic aberration, contrasting with a usual polyclonal immunoglobulin expression. To determine more precisely the distribution of the chromosomal abnormality within the peripheral lymphocyte population and study the relationship between the +i(3)(q10) and the bilobulated character, we investigated three new cases of PPBL displaying the cytogenetic abnormality on the karyotype, using a technique of simultaneous fluorescence immunophenotyping and interphase cytogenetics (FICTION). We demonstrated that the +i(3)(q10) was restricted to the B lymphocytes, independently of the κ or λ light chain isotype and was present in both bilobulated and non‐bilobulated cells. Therefore it is likely that the cytogenetic abnormality occurs at an early stage of lymphocyte differentiation in a precursor cell already committed to the B‐cell lineage, before any rearrangement of immunoglobulin genes has taken place.

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“…More recently, Callet-Bauchu and colleagues have reported three additional subjects with PPBL; +i(3q) was observed in 6-12% of metaphase cells in all three patients after stimulation with TPA. 5 These findings were also confirmed by FISH analysis. Using a technique of simultaneous fluorescence immunophenotyping and interphase cytogenetics (FICTION) they demonstrated that the +i(3q) was restricted to B lymphocytes and present in both binucleated and non-binucleated lymphocytes.…”

Intravascular bone marrow accumulation in persistent polyclonal lymphocytosis: a misleading feature for B-cell neoplasm

“…Among the cases reported in the literature, one patient developed a malignant pulmonary blastoma 11 years after diagnosis, 32 another patient developed a large-cell lymphoma 19 years after initial PPBL diagnosis 33 and one patient presented concomitantly polyclonal lymphocytosis and malignant gastric non-Hodgkin's lymphoma. 31 With a 3.6 years follow-up, we did not observe any lymphoproliferative disease.…”

“…These genetic aberrations were found to be restricted to B cells (PPBL and normal lymphocytes), indicating the presence of a contrasting restricted cytogenetic population in PPBL patients. 31 The long and indolent evolution in most patients showing multiple t(14;18) translocations confirms that this rearrangement is not sufficient to confer tumorigenicity, even though Bcl-2 is a well-recognized proto-oncogene. Among the cases reported in the literature, one patient developed a malignant pulmonary blastoma 11 years after diagnosis, 32 another patient developed a large-cell lymphoma 19 years after initial PPBL diagnosis 33 and one patient presented concomitantly polyclonal lymphocytosis and malignant gastric non-Hodgkin's lymphoma.…”

Regression of lymphoproliferative disorder after treatment for hepatitis C virus infection in a patient with partial trisomy 3, Bcl-2 overexpression, and type II cryoglobulinemia

“…The lymphoproliferation had characteristics common to both the B-cell lymphocytosis associated with partial trisomy 3 and very low grade subtypes of MZBC lymphomas. [12][13][14] The splenomegaly and elevated LDH that responded to IFN therapy were suggestive of splenic lymphoma. The monoclonal B cells had MZBC markers and were WA ϩ ; 25% or more of B-cell lymphomas associated with HCV-type II cryoglobulinemia arise from WA ϩ B cells although correlation with MZBC markers has not been assessed.…”

“…[11][12][13] Further studies are needed to determine the prevalance of these abnormalities in HCV infection with and without type II cryoglobulimenia and their possible physiologic and/or pathophysiologic implications.…”