Category Archives: Lymph Node

Uncategorized, Organ Systems, Lymph Node, WHO Classification

Classical Hodgkin Lymphoma – Immunohistochemsitry

CHL Immunohistochemical Features:
Positive in the malignant cells in almost all cases.  Membrane staining with Golgi area positivity.
Positive in the malignant cells in a majority of cases (75-85%).  The staining pattern is similar to CD30.  It should be noted that there is a lot a variability lab to lab in the performance of the antibody.
Usually negative
Dim expression in the lymphoma cells in >90% of the cases.  Helpful in differentiating cases from anapestic large cell lymphoma, which may be CD45 negative.
Usually negative, but may have dim variable subset expression in up to 20% of cases.
Rarely positive in the lymphoma cells.
Usually positive and usually intense.
EBV
Variable
Rarely positive and usually weak if positive.
OCT-2
Negative in 90% of cases.
Negative in 90% of cases.
Negative or dim expression
Negative.
 
References
Hematopathology. [edited by] Jaffe, ES. 1st. ed. Elsevier, Inc. © 2011.
 
Robbins and Cotran Pathologic Basis of Disease.  V Kumar, et al. 9th Edition. Elsevier Saunders. 2015.
 
WHO Classification of Tumors of Haematopoietic and Lymphoid Tissues.  SH Swerdlow, et al. International Agency for Research on Cancer. Lyon, 2008.
Organ Systems, Lymph Node, WHO Classification

Classical Hodgkin Lymphoma (CHL)

NF-κB transcription factor is a common event, which may occur through EBV infection (hence some cases positive for EBV) or other mechanism.  It is thought this process results in survival of germinal center B-cells, which would otherwise undergo apoptosis.  Hodgkin lymphoma cells typically represent a small number within the lesional tissue.  Hodgkin cells secrete varying cytokines that recruit other inflammatory cells, which make up the characteristic milieu (histiocytes, plasma cells, T-cell, and eosinophils).
 
Reed-Sternberg (HRS) cells are defined by two separate nuclear lobes with large nucleoli.  Mononuclear neoplastic cells are referred to as Hodgkin cells.  There is often a spectrum in appearance of the neoplastic cells with some HRS types but they may a minority.  Granulomatous inflammation may be present in biopsy specimens, and it important not to dismiss the granulomatous inflammation as the primary pathology (especially in small biopsy samples).
Categorization
Characteristic Immunohistochemical Features:
Positive in the malignant cells in almost all cases.  Membrane staining with Golgi area positivity.
Positive in the malignant cells in a majority of cases (75-85%).  The staining pattern is similar to CD30.  It should be noted that there is a lot a variability lab to lab in the performance of the antibody.
Usually negative
Dim expression in the lymphoma cells in >90% of the cases.  Helpful in differentiating cases from anapestic large cell lymphoma, which may be CD45 negative.
Usually negative, but may have dim variable subset expression in up to 20% of cases.
Rarely positive in the lymphoma cells.
Usually positive and usually intense.
EBV
Variable
Rarely positive and usually weak if positive.
OCT-2
Negative in 90% of cases.
Negative in 90% of cases.
Negative.
 
General
Brentuximab vedotin (Adcetris) is an anti-CD30 monoclonal antibody used to treat anaplastic large cell lymphoma and relapsed or refractory Hodgkin lymphoma.  Ongoing research with promise is active in other CD30 positive neoplastic processes. 
References
Hematopathology. [edited by] Jaffe, ES. 1st. ed. Elsevier, Inc. © 2011.
 
Robbins and Cotran Pathologic Basis of Disease.  V Kumar, et al. 9th Edition. Elsevier Saunders. 2015.
 
WHO Classification of Tumors of Haematopoietic and Lymphoid Tissues.  SH Swerdlow, et al. International Agency for Research on Cancer. Lyon, 2008.
 
Ansell SM. Brentuximab vedotin. Blood. 2014. doi:10.1182/blood-2014-06
Organ Systems, Lymph Node, WHO Classification

Nodular Lymphocyte Predominate Hodgkin Lymphoma (NLPHL)

Nodular Lymphocyte Predominate Hodgkin Lymphoma (NLPHL) epresents approximately 5-10% of Hodgkin lymphoma cases (predominately male, 30-50 y/o) and has slightly different appearing neoplastic cells (popcorn cells – folded/multilobuated usually with multiple nucleoli).  The cellular background is typically composed of small lymphocytes and histiocytes.  Some plasma cells may be present at the peripheral of the nodule.  Neutrophils and eosinophils are not typically present.  The immunophenotype of lymphocyte predominate (LP) cells in NLPHL  is different from classical Hodgkin lymphoma.  The LP  cells express CD20 and BCL 6, but are typically negative for CD30 and CD15.  Dim expression of CD30 can be seen.

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Organ Systems, Bone Marrow, Lymph Node, WHO Classification

Blastic Plasmacytoid Dendritic Cell Neoplasm

IHC Expression Pattern
Positive
Positive
CD45RA
Positive
Positive.  Rare cases may be negative, but should express CD4, CD123, and TCL1.
Expressed in ~50% of cases (small cytoplasmic dots)
Often Positive
Negative
MPO
Negative
Negative in tissue sections (may be + by flow)
Negative
Negative
EBV-EBER
Negative
TCL-1
Positive
References
Hematopathology. [edited by] Jaffe, ES. 1st. ed. Elsevier, Inc. © 2011.
Organ Systems, Bone Marrow, Lymph Node, WHO Classification

Mature B-Cell Neoplasms

Organ Systems, Bone Marrow, Lymph Node, WHO Classification

Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma (CLL/SLL)

CLL/SLL represents a B-cell neoplasm of small lymphocytes which involve a combination of peripheral blood, bone marrow, and/or lymph nodes.  When peripheral blood predominates, then it is referred to as CLL, and when it presents as predominately nodal involvement it is referred to as SLL.  This is the same disorder with different manifestations.

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Organ Systems, Bone Marrow, Lymph Node, WHO Classification

Monoclonal B-Cell Lymphocytosis (MBL)

Monoclonal B-cell lymphocytosis (MBL) was defined by the International Familial CLL consortium in 2005 as a monoclonal B-cell lymphocyte population in the peripheral blood <5,000/uL without evidence of lymphadenopathy (i.e. SLL), an autoimmune/infectious disease or other features diagnostic of a B-cell lymphoproliferative disorder.  The 2016 WHO hematopathology revision dropped the requirement of cytopenias or disease related symptoms as adequate to make the diagnosis of CLL.

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Organ Systems, Bone Marrow, Lymph Node, WHO Classification

Follicular Lymphoma

Follicular Lymphoma (FL) is a mature B-cell lymphoma, which recapitulates or resembles germinal center B-cells.  Most cases (~85%) harbor the characteristic t(14;18), which juxtaposes the BCL-2 gene on chromosome 18 with the IgH gene on chromosome 14 (and hence BCL-2 IHC protein expression).  Most patients (~80-85) will present with advanced disease (stage III/IV), and bone marrow involvement is found in ~40% of cases with characteristic paratrabecular aggregates (mantle cell lymphoma and lymphoplasmacytic lymphoma may also have paratrabecular lymphoid aggregates).  Most of the cases that lack the t(14;18) IgH/BCL-2 translocation (and are BCL-2 negative) are typically grade 3 FLs with a BCL-6 translocation (~10-15%).  BCL-6 translocations can be evaluated for by FISH analysis, but the finding is NOT specific for FL.
 
Over time 30-50% of cases transform to diffuse large B-cell lymphoma (DLBCL).  In a small subset of transformations, a second “hit” with a MYC translocation will occur resulting in a very aggressive high grade large B-cell lymphoma: the so-called “double hit” lymphoma. 
Morphology
FL usually has at least a component of nodularity (+/- diffuse areas).  There are two cell types that make up FL, centrocytes and centroblasts.  Centrocytes are small cleaved cells with folded irregular nuclei.  Centorblasts are large cells with more open chromatin, multiple nucleoli, and more cytoplasm compared to centrocytes.  
 
Sometimes FL can have patterns that resemble marginal zone lymphoma, and can even have plasmacytic differentiation.  Therefore, it is important that a panel of markers be used to identify (or exclude) evidence of germinal center differentiation.  Occasional cases can have Hodgkin-like cells.
Immunophenotype 
Marker
Comment
Negative
Positive
Positive
Positive
  • Grade 1 – ~90%
  • Grade 2 – ~70%
  • Grade 3 – ~60%
Positive (~90%), negative cases do not contain the t(14;18), which is more common in grade 3 cases
  • Grade 1 – >90% + for BCL-2
  • Grade 2 – >80% + for BCL-2
  • Grade 3 – 50-70% + BCL-2
Positive, (~88%)
CD35
Highlights the follicular dendritic meshwork associated with FL.
Usually negative, higher grade lesions may be positive
Variable, shows low expression in low-grade processes, in distinct contrast to the high proliferation index and polarity associated with reactive germinal centers.
Negative
 
  
FL is typically expresses CD19, CD20, CD10, Bcl-6, and BCL-2 (~90%).  CD5 is not expressed in FL.  
  • Normal reactive germinal centers do not express Bcl-2.  In 90% of cases of FL, bcl-2 is expressed, which serves as a diagnostic tissue marker in lymphoma sections.
  • CD23 expression by flow cytometry has been associated with lower grade FLs (e.g. grade 1 & 2) and better survival.
Grading
  • Grade 1 & 2:  <= 15 centroblasts/HPF (based on 0.159 mm² HPF)
  • Grade 3:  > 15 centroblasts/HPF (based on 0.159 mm² HPF)
    • 3A:  Centrocytes present in the background
    • 3B:  NO centrocytes present in the background (not associated with the IgH/BCL-2 rearrangement, and usually lacks expression of CD10 and BCL-2; often MUM-1+)
Grade 1 & 2 behave in a similar fashion as a low grade lymphoma.  Grade 3 FL behaves as an intermediate grade lymphoma.  Grading of FL with counting of large cells must take into consideration the field diameter of the microscope being used.  The counts above are based on a F.N. 18 (0.159 mm² @ 40X).  Most convention pathology scopes today are F.N. 22 (0.247 mm² @ 40X), and adjustments are necessary.
Pattern
  • Predominately follicular:  >75% follicular/nodular architecture
  • Follicular and diffuse:  25-75% Diffuse areas or follicular/nodular architecture
  • Preominately diffuse:  <25% follicular/nodular areas (diffuse areas of otherwise grade 3 FL, then that component should be described as a separate component of diffuse large B-cell lymphoma)
Special Subtypes 
  • Large B-Cell Lymphoma with IRF4 Rearrangement
  • Pediatric Follicular Lymphoma
    • Occurs in children and young adults with an excellent prognosis, marked male predilection
    • The morphology is high-grade (FL grade 3) appearing
      • BCL-2 negative, lacK t(14;18)
      • CD10 + (usually)
      • MUM-1 negative
    • Associated with TNFRSF14 deletions of mutations
    • Localized process, usually in the head and neck area
  • Duodenal Follicular Lymphoma
    • Localized lesion
    • Grade 1-2 pattern
    • CD10/BCL-2 +
    • t(14;18) present
    • Lacks follicular dendritic meshwork
    • Ki-67, low expression
    • Excellent prognosis
  • Predominately Diffuse Follicular Lymphoma with 1p36 deletion
    • Localized mass (often inguinal)
    • Diffuse pattern, grade 1/2 
    • Excellent prognosis
    • Immunophenotype:  CD20+, CD10+, BCL-2+, BCL-6+, CD23+ (subset of cases)
    • t(14;18) NOT present
    • 1p36 deletion (not specific)
    • Lacks Bcl-2 rearrangement
  • Primary Cutaneous Follicular Lymphoma 
  • In Situ Follicular Neoplasm (ISFN)
References
Robbins and Cotran Pathologic Basis of Disease.  V Kumar, et al. 9th Edition. Elsevier Saunders. 2015. pp. 594-595.
 
Fedoriw Y, Dogan A. The Expanding Spectrum of Follicular Lymphoma. Surg Pathol Clin. 2016;9: 29–40. doi:10.1016/j.path.2015.11.001
 
Swerdlow SH, Campo E, Pileri SA, Harris NL, Stein H, Siebert R, et al. The 2016 revision of the World Health Organization classification of lymphoid neoplasms. Blood. 2016;127: 2375–2390. doi:10.1182/blood-2016-01-643569
 
Xerri L, Dirnhofer S, Quintanilla-Martinez L, Sander B, Chan JKC, Campo E, et al. The heterogeneity of follicular lymphomas: from early development to transformation. Virchows Arch. 2016;468: 127–139. doi:10.1007/s00428-015-1864-y
 
MD DY-PW, BacSc F. A case of t (14; 18)-negative follicular lymphoma with atypical immunophenotype: usefulness of immunoarchitecture of Ki67, CD79a and follicular dendritic cell …. … Malaysian journal of …. 2014.
 
Boyd SD, Natkunam Y, Allen JR, Warnke RA. Selective immunophenotyping for diagnosis of B-cell neoplasms: immunohistochemistry and flow cytometry strategies and results. Appl Immunohistochem Mol Morphol. 2013;21: 116–131. doi:10.1097/PAI.0b013e31825d550a
 
Cook JR. Nodal and leukemic small B-cell neoplasms. Mod Pathol. 2013;26 Suppl 1: S15–28. doi:10.1038/modpathol.2012.180
 
Olteanu H, Fenske TS, Harrington AM, Szabo A, He P, Kroft SH. CD23 Expression in Follicular Lymphoma: Clinicopathologic Correlations. Am J Clin Pathol. 2011;135: 46–53. doi:10.1309/AJCP27YWLIQRAJPW
 
Gradowski JF, Jaffe ES, Warnke RA, Pittaluga S, Surti U, Gole LA, et al. Follicular lymphomas with plasmacytic differentiation include two subtypes. Mod Pathol. 2010;23: 71–79. doi:10.1038/modpathol.2009.146
 
Katzenberger T, Kalla J, Leich E, Stöcklein H, Hartmann E, Barnickel S, et al. A distinctive subtype of t(14;18)-negative nodal follicular non-Hodgkin lymphoma characterized by a predominantly diffuse growth pattern and deletions in the chromosomal region 1p36. Blood. 2009;113: 1053–1061. doi:10.1182/blood-2008-07-168682
 
Bayerl MG, Bentley G, Bellan C, Leoncini L, Ehmann WC, Palutke M. Lacunar and reed-sternberg-like cells in follicular lymphomas are clonally related to the centrocytic and centroblastic cells as demonstrated by laser capture microdissection. Am J Clin Pathol. 2004;122: 858–864. doi:10.1309/PMR8-6PHK-K4J3-RUH3
Organ Systems, Bone Marrow, Lymph Node, WHO Classification

Lymphomatoid Granulomatosis

Lymphomatoid Granulomatosis (LYG) is a B-cell neoplasm of EBV + B-cells with characteristic anglocentric and angiodestructive features typically associated with some form of immunodeficiency.
 
LYG is an uncommon lymphoproliferative disorder and is not usually found in lymph nodes or spleen.  Pulmonary involvement is present in >90% of cases, and other organs (e.g. brain, kidney, skin, liver) can be variably affected.  
Morphology
LYG can have a varied appearance, but usually has a predominate background of small lymphocytes (T-cells), plasma cells, and histiocytes.  Eosinophils and neutrophils are not a typical finding.  Neoplastic EBV + B-cells can have a variable appearance ranging from immunoblast-like cells to morphologies similar to Hodgkin cells.  The lymphoid infiltrate has an anglocentric and angiodestructive pattern, which may result in necrosis.  If the pattern is of large cells in diffuse sheets, then the diagnosis of EBV+ diffuse large B-cell lymphoma should be made.
 
Differential diagnosis – Extranodal NK/T-cell lymphoma, nasal type is also an EBV+ tumor with an angiodestructive growth pattern.
Immunophenotype
  • EBV+ Neoplastic B-cells
  • CD20+
  • CD30 variably positive
  • Background T-cells
Grading
  • Grade 1 – < 5 EBV+ cells/HPF, polymorphic lymphoid infiltrate (large atypical cells rare/absent), No/focal necrosis.
  • Grade 2 – 5-20 EBV+ cells/HPF (small clusters of B-cells by CD20), occasional large atypical/transformed cells.
  • Grade 3 – > 50 EBV+ cells/HPF, numerous large atypical CD20+ B-cells (may form large aggregates)
References
WHO Classification of Tumors of Haematopoietic and Lymphoid Tissues.  SH Swerdlow, et al. International Agency for Research on Cancer. Lyon, 2008. p. 247-249