Mature B cell Flashcards
Marginal zone diagnosis
Diagnosis requires either spleen histology or, alternatively, the documentation of a typical cell morphology and immunophenotype on blood cells coupled with the detection of intrasinusoidal infiltration by CD20+ cells in the bone marrow. Among B-cell tumors, deletion of 7q and NOTCh 2 is specific
Presenting features Splenic MZL
in advanced-stage SMZL, symptomatic splenomegaly and cytopenia can be the presenting features
Lymphocytosis
Approximately 20% of patients show an autoimmune manifestation,1 including autoimmune hemolytic anemia, immune thrombocytopenia, cold agglutinin disease, circulating anticoagulants, acquired von Willebrand disease, or angioedema as a result of acquired C1-esterase inhibitor deficiency
Lymphocytes in SMZL
typical cell morphology - round nuclei, condensed chromatin, and basophilic cytoplasm with polar short villi (so-called “villous lymphocytes”).
Heterogeneity in blood morphology is common,-small lymphoid cells without specific features, to various degrees of monocytoid and plasmacytoid differentiation.
Large cells, although rare, may suggest disease transformation into a large-cell lymphoma.15
Bone marrow trephine MZL
sinusoidal pattern of infiltration is often detectable, usually combined with an interstitial and nodular component.
this pattern may also be observed, in several low-grade B-cell lymphomas.
a search for the dendritic meshwork more commonly present and disrupted in SMZL,18 is helpful in many instances.
Extra nodal marginal malt associations
Hep c H pylori gut C psitticae eye Sjorgens mouth Hashimotos Skin (assoc with Borrelia borgdorferi),
DDx for IgM paraprotein
Waldenstroms
CLL
Marginal zone
Trisomy 12 CLL
Atypical morphology
Inc prolymphocytic circulating cells
Decreased score on CLL flow - CD79b, FMC7 and surface Ig mod/strong
Assoc w worse prognosis esp when w notch p mutations
DDx for splenic based lymphoma
SMZL HCL lPL B-PLL FOLLICULAR McL
Trisomy 12 CLL
atypical morphology
increased circulating prolymphocytoid cells low CLL scores on immunophenotyping due to expression of CD79b, FMC7 and surface Ig mod/strong ; this has been referred to as variant CLL 1. Furthermore, it may also be associated with a less favourable prognosis particularly in cases with associated NOTCH1 mutations 2.
If matut s < 3- how do you rule out mantle cell
Immunostaining of bone marrow trephine sections or lymph node for nuclear cyclin D1
(ii) FISH for t(11:14) using blood, BM or lymph node
Loss of tp 53
strongly associated with poor
response to alkylating agents and purine analogues.
Diagnostic criteria for b pll
Lymphocytosis with more than 55% prolymphocytes
Immunophenotype SmIgM/D strong, CD20 strong,
CD22/CD79b strong, FMC7+, CD5+ in 33% patients.
CD23 usually negative.
Immunohistochemistry for Cyclin D1 in all cases to
exclude MCL and/or FISH for t(11;14).
Peripheral blood film in lpl
marked rouleaux formation and variable
numbers of small lymphocytes, lymphoplasmacytoid cells and plasma cells, the
latter rarely present in high numbers. Anaemia, neutropenia and
thrombocytopenia may occur because of hypersplenism and/or bone marrow
failure
Flow for LPL
Immunophenotype: Sm IgM+ CD5- CD10- CD19+
CD20+ CD22+ CD23- CD25+ CD27+ FMC7+
CD103- CD138-.
Additional inves
Other tests in LPL
Plasma viscosity, tests of renal and hepatic function
Direct antiglobulin test, cold agglutinin titre and
cryoglobulins
Beta 2 microglobulin