Hematopathology Flashcards
CD5+ small B cell lymphomas
CLL/SLL and Mantle Cell Lymphoma
Differentiate the two CD5+ small B cell lymphomas
CLL/SLL vs Mantle Cell Lymphoma
CD23 more likely positive in CLL/SLL (negative in MCL)
CYCLIND1 –> negative in CLL/SLL
*watch out for cyclinD1 (BLC1) in proliferation center of CLL –> SOX11 positive is ALWAYS mantle cell lymphoma
t(11;14) –> Mantle Cell
CD43 in a small B cell lymphoma
Positive –> CLL/SLL and Mantle cell and Marginal zone (majority)
Negative –> follicular
t(14;18) in a small B cell lymphoma
Follicular lymphoma
CD10+
BCL6+
B-cell markers positive (CD20, PAX5, CD79a)
t(11;14) in a small B cell lymphoma
Mantle Cell lymphoma
CyclinD1
Sox11 (most specific)
BCL1 (antibody for cyclin D1)
Classic Immunophenotype for CLL/SLL
CD5+
CD23+
CD200+
LEF1+
FMC7+
CD10-
CyclinD1- (except prolif centers)
Sox11-
BCL6-
CD5+
CLL/SLL
Mantle cell
Order CD10
order cyclinD1/sox11
order CD200
order LEF1
CD10+
Follicular lymphoma
*also Burkitt
CD5-
follicular lymphoma
marginal zone lymphoma
CD200+
think CLL/SLL
LEF-1
immediately think CLL/SLL
you see a nodular germinal center like area with CyclinD1 expression
CLL proliferation center vs. Mantle
order Sox11 (+ only in Mantle cell lymphoma)
t(14:18)(q32;q21) translocation
follicular lymphoma
BCL2 gene is recurrently rearranged in up to 95% of FL cases due to t(14;18))q32;q21).
Follicular Lymphoma characteristic translocation
t(14:18)(q32;q21) translocation
*not defining
FL is characterized genetically by a t(14:18)(q32;q21) translocation, with rearrangement of the BCL2 gene, in up to 95% of cases. This translocation can be detected by FISH on cytologic material in over 80% of cases,
What is characterized genetically by a t(14:18)(q32;q21) translocation, with rearrangement of the BCL2 gene, in up to 95% of cases. This translocation can be detected by FISH on cytologic material in over 80% of cases,
Follicular lymphoma
A green probe for igh (immunoglobulin heavy chain) at 14q32 and a red probe for bcl2 at 18q21 come together to give a yellow signal when there is a translocation.
FISH results for follicular lymphoma
What is Marginal Zone lymphoma?
Marginal zone lymphoma is an indolent, low-grade B-cell lymphoma that is divided into nodal and extranodal types. The extranodal type is synonymous with mucosa-associated lymphoid tissue (MALT) lymphoma and is more common than the nodal type, accounting for 7% to 8% of all B-cell lymphomas.
around 8% of all B-cell lymphomas…think predominantly extranodal
Marginal zone lymphoma is an indolent, low-grade B-cell lymphoma that is divided into nodal and extranodal types. The extranodal type is synonymous with mucosa-associated lymphoid tissue (MALT) lymphoma and is more common than the nodal type, accounting for 7% to 8% of all B-cell lymphomas.
MALT lymphoma is an extranodal manifestation of…
Marginal Zone Lymphoma
The two diagnoses are the same, just MALT is more accurately tied with the predominant extranodal manifestation of Marginal Zone Lymphoma
Where might you see FNA of marginal zone?
Although MALT lymphomas occur in a variety of sites, FNA cytologists typically only encounter them in specimens from the salivary gland, lung, lacrimal gland, thyroid, breast, and skin.
B cell lymphoma with a strong association with autoimmune disorders such as Hashimoto thyroiditis and Sjögren syndrome.
Marginal Zone Lymphoma
AKA - MALT lymphoma
*MALT = extranodal marginal zone
What is CLL/SLL?
Small lymphocytic lymphoma (SLL) comprises about 7% of non-Hodgkin lymphoma. 26 It is an indolent and typically incurable neoplasm of older adults. Disease is widespread (nodally and extranodally) at the time of diagnosis, usually including peripheral blood and bone marrow involvement (the latter perversely referred to by a different name: chronic lymphocytic leukemia (CLL)).
Which two B cell lymphomas are about equal in causing about 8% of all B-cell lymphomas?
CLL/SLL and Marginal Zone Lymphoma
CD5 should differentiate
CD5+ —> CLL/SLL
CD5- –> marginal zone
MLL rearrangement in ALL means what?
The t(4;11)(q21;q23) translocation and the associated MLL rearrangement are seen in ALL and the prognosis is very poor.
Is it a good thing that a pediatric bone marrow shows ALL with MLL rearrangement?
NO
The t(4;11)(q21;q23) translocation and the associated MLL rearrangement are seen in ALL and the prognosis is very poor.
What can (FISH) analysis was performed using a myeloid/lymphoid leukemia (MLL) gene dual-color break-apart probe tell you?
prognostic finding in ALL
t(4;11)(q21;q23) translocation
Chromosome changes most common in MDS
The chromosome changes frequently seen in MDS are del(5q)/monosomy 5, del(7q)/monosomy 7, del(20q)/monosomy 20, and trisomy 8.
Burkitt lymphoma has 3 associated rearragements…
t(8;14)(q24;q32),
t(8;22)(q24;q11),
t(2;8)(p11;q24)
characteristic chromosome translocations in BL.
Translocation defining of APL
APL is associated with chromosome translocation t(15;17)(q22;q21)
What drug/chemo treatment is associated with MLL rearranged leukemia later on?
Topoisomerase II inhibitors (etoposide) are associated with MLL rearrangement.
*methotrexate is often used to treat MLL leukemia
*MLL is mixed lineage leukemia, can happen in ALL or AML
*in AML, this rearrangement gives a monoblastic differentiation to AML
Which rearrangement in AML can lead to monoblastic differentiation?
MLL
t(4;11)(q21;q23) translocation and the associated MLL rearrangement
Bone marrow shows acute leukemia. FLOW:
Flow cytometric analysis of the marrow after exclusion of the CD45-negative to dim gate, showed a phenotype of CD19+, CD79a+, CD22+, CD10+, CD20–, CD34+ (partial), CD117–, HLA-DR+, CD43+, CD38+, CD52+, and TdT+.
Pre-B ALL
*look for hyperdiploidy status for a good prognosis
immunohistochemical staining for Bcl-6, and t(3;14)(q27;q32) translocation are characteristic ….
DLBCL.
DLBCL best IHC and FISH results for diagnosis
immunohistochemical staining for Bcl-6, and t(3;14)(q27;q32) translocation are characteristic of DLBCL.
The t(11;18) translocation involves the API2 and MALT1 genes and is mainly detected in…
gastric and pulmonary MALT lymphomas
Most important translocation MALT lymphomas of the GI tract
t(11;18)(q21;q21) –> API2 and MALT1 fusion
*confers resistance to h pylori eradication treatment
most common translocation in ALCL
anaplastic large cell lymphoma
*t(2;5)(p23;q35)
*CD30 positive, ALK positive probably (80%)
*EMA positive
*DDX with hodgkin, melanoma, DLBCL