Flashcards in Lymph Nodes Deck (343)
SLL/CLL: Progression to DLBCL.
Occurs in 5-10% of patients.
SLL/CLL: Expression of cyclin D1 (3).
Dim expression in the proliferation centers occurs rarely.
Should not cause a diagnosis of mantle-cell lymphoma.
Follicular lymphoma: Involvement of extranodal lymphoid organs.
Occurs in most patients.
Follicular lymphoma: Sites of primary extranodal disease (3).
A. Mantle zones.
B. May be ruptured, with extranodal extension of the lymphoma.
Follicular lymphoma: Grading.
Grade 2 has 6-15 centroblasts per hpf.
Grades 1 and 2 are considered low grade.
Grade 3A: Centrocytes and centroblasts.
Grade 3B: Centroblasts only.
Follicular lymphoma: Diagnosis of diffuse area consisting mainly of centroblasts.
An additional diagnosis of DLBCL is made.
Follicular lymphoma: Expression of CD20 on flow cytometry.
Follicular lymphoma: IHC (3).
Positive: CD10, Bcl-2, Bcl-6.
Follicular lymphoma: Immunochemical anomalies of high-grade tumors (2).
May lack CD10.
May lack Bcl-2.
May express Mum-1.
Follicular lymphoma: Use of immunohistochemistry in grading.
Ki-67 . . .
- Less than 20% of cells proliferate: Low grade.
- More than 20%: High grade.
Follicular lymphoma: Additional immunohistochemistry.
CD21 and CD23:
- Reveal effaced germinal centers in follicular lymphoma.
- Not so in DLBCL.
Follicular lymphoma: Rearrangements (2).
t(14;18) :: IGH-BCL2 in most cases.
Rearrangement of BCL6 in some cases, esp. of grade 3B.
Follicular lymphoma: Genotype of aberrant type.
Cases that lack t(14;18) and expression of Bcl-2 have postgerminal-center genes.
Follicular lymphoma vs. reactive follicular hyperplasia: Proliferation rate.
Reactive follicular hyperplasia: Greater than 90%.
Mantle-cell lymphoma: Frequency of extranodal disease at presentation.
Present in most patients.
A. Median survival.
B. Presentation that may correlate with a better prognosis.
A. Three to four years.
B. Absence of nodal disease.
Mantle-cell lymphoma: Non-malignant histologic features (2).
Hyalinized small vessels.
Scattered epithelioid histiocytes containing no nuclear débris.
Mantle-cell lymphoma: Variants (2).
- Fine chromatin.
- Twenty to thirty mitotic figures per 10 hpf.
Pleomorphic: Large, pleomorphic cells with large nucleoli.
Mantle-cell lymphoma: Effect of proliferation of tumor cells on prognosis (2).
Each of these can worsen the prognosis:
- Mitotic rate greater than 10 per hpf.
- Proliferation rate of greater than 40% by Ki-67.
Mantle-cell lymphoma: Newer immunohistochemical marker.
Mantle-cell lymphoma: Translocation.
t(11;14) :: CCND1-IGH.
Mantle-cell lymphoma: Immunophenotypic aberrations (2).
Rare: Absence of CD5, expression of CD23 or CD10.
Very rare: Absence of cyclin D1 and t(11;14).
Mantle-cell lymphoma: How to recognize cases that lack expression of cyclin D1 and t(11;14).
They express SOX11.
Nodal marginal-zone lymphoma: Presentation.
Asymptomatic lymphadenopathy but with disease in advanced stage.
Nodal marginal-zone lymphoma: Architecture.
Cells surround reactive lymphoid follicles and often infiltrate them (follicular colonization).
Nodal marginal-zone lymphoma: Cellular components.
Monocytoid B cells.
Nodal marginal-zone lymphoma: Immunophenotype (2,1,1).
Bright: CD20, sIg.
Usually positive: Bcl-2.
Variable (50%): CD43.
Nodal marginal-zone lymphoma: Cytogenetics (2).
A few cases may show +3, +7, or +18.
Translocations involving BCL10 and MALT1 are not observed.