All posts by peferguson

Organ Systems, Lymph Node, WHO Classification

Angioimmunoblastic T-Cell Lymphoma

Immunophenotypic Expression Pattern
Marker
Comment
Positive
Positive
Positive
Positive
Positive
Positive (often numerous reactive T-cells will be present)
Positive in the neoplastic cells in ~50% of cases
CXCL13
Positive in a majority of cases (marker of follicular helper T-cells)
EBV (EBER)
Positive in reactive B-cells
Negative
Expanded FDC network
It is not uncommon for some of the T-cell markers to be dropped.
References
Parker, A., et. al.  “Best Practice in Lymphoma Diagnosis and Reporting.”  British Committee for Standards in Haematology, Royal College of Pathologists.  April, 2010.
Organ Systems, Lymph Node, WHO Classification

Peripheral T-Cell Lymphoma, NOS (PTCL-NOS)

PTCL-NOS is a heterogeneous group of mature T-cell lymphoproliferative disorders, which do not fit well into other defined categories, and have a generally poor outcome.  While there may be a lot of variability to the IHC findings, the following are some general characteristics:
 
  • CD4>CD8 expression.
  • Frequent loss of antigen expression from T-cell markers (CD4, CD5, CD7, CD8, CD52)
  • CD30 is usually negative
  • CD56 is usually negative
  • CD10 is usually negative
  • CLCX13 – negative
  • BCL6 – negative
References
Hematopathology. [edited by] Jaffe, ES. 1st. ed. Elsevier, Inc. © 2011.
Organ Systems, Bone Marrow, Lymph Node, WHO Classification

Sezary Syndrome

Sezary syndrome (SS) is a generalized disease including a leukemia component.  Histologically, the skin findings may be similar to mycosis fungicides.
Immunophenotypic Expression Pattern
Marker
Comment
Positive
Positive
Positive (most cases)
Positive
Usually Negative
Usually Negative
References
Hematopathology. [edited by] Jaffe, ES. 1st. ed. Elsevier, Inc. © 2011. p. 299.
Organ Systems, Bone Marrow, Lymph Node, WHO Classification

Mycosis Fungoides

Mycosis Fungoides (MF) is an epidermotropic cutaneous T-Cell lymphoma and accounts for ~50% of cutaneous lymphomas overall.
 
Immunophenotypic Expression Pattern
Marker
Comment
Positive
Positive
Usually Positive
Positive
Usually Negative (some cases may be CD8+)
Usually Negative
TIA-1
Negative (rarely +)
References
Hematopathology. [edited by] Jaffe, ES. 1st. ed. Elsevier, Inc. © 2011.
Organ Systems, Lymph Node, WHO Classification

Subcutaneous Panniculitis-Like T-Cell Lymphoma

This is a rare lymphoma (<1% of non-Hodgkin lymphomas), which presents as subcutaneous nodules on the skin.
Immunophenotypic Expression Pattern
Marker
Comment
Positive (usually)
TIA-1
Positive
Positive
Perforin
Positive
Negative
βF1
Positive (alpha beta T-cell phenotype)
EBV (EBER)
Negative
Refernces
Hematopathology. [edited by] Jaffe, ES. 1st. ed. Elsevier, Inc. © 2011.  pp. 294-95.
Organ Systems, Bone Marrow, Lymph Node, WHO Classification

Hepatosplenic T-Cell Lymphoma

Immunophenotypic Expression Pattern
 
Marker
Comment
Positive
Positive
Negative
Negative
+/-
Negative (rare +)
Positive (+/-)
EBV (EBER)
Negative
Usually Negative
Perforin
Usually Negative (rare +)
TIA-1
Positive
Negative
Negative
References
Parker, A., et. al.  “Best Practice in Lymphoma Diagnosis and Reporting.”  British Committee for Standards in Haematology, Royal College of Pathologists.  April, 2010.
 
Hematopathology. [edited by] Jaffe, ES. 1st. ed. Elsevier, Inc. © 2011.  pp. 292-93.
Organ Systems, Bone Marrow, Lymph Node, WHO Classification

Adult T-Cell Leukemia/Lymphoma

This is an aggressive lympho-proliferative disorder associated with Human T-Cell Leukemia Virus Type I (HTLV-1).  Most patients present with widespread lymphadenopathy and peripheral blood involvement.
Immunophenotypic Expression Pattern
Marker
Comment
Positive
Positive
Positive
Usually Negative
Usually Positive
Usually negative (there are occasional CD8+/CD4= or CD8+/CD4+ cases)
Strongly expressed in almost all cases.
May stain some large transformed cells.
Negative
TIA-1
Negative
Negative
HTLV-1
Positive.  There is no IHC stain, but this is an important test that can be done on the peripheral blood.
References
Hematopathology. [edited by] Jaffe, ES. 1st. ed. Elsevier, Inc. © 2011.  pp. 281-84.
Organ Systems, Lymph Node, WHO Classification

EBV+ T-Cell Lymphoproliferative Disorders of Childhood

This is a rare disorder of clonal EBV-infected T-cells, which contain an activated cytotoxic phenotype.  There is some clinicopathologic overlap with aggressive NK-cell leukemia.  May be associated with acute or chronic EBV infection.
Immunophenotypic Expression Pattern
Marker
Comment
Positive
Positive
Negative
TIA-1
Positive
Positivity is associated with chronic active EBV infection.
Positivity is associated with acute primary EBV infection.
EBV (EBER)
Positive
References
Hematopathology. [edited by] Jaffe, ES. 1st. ed. Elsevier, Inc. © 2011.
Organ Systems, Bone Marrow, WHO Classification

Aggressive NK-Cell Leukemia

This is an “aggressive” leukemia/lymphoma disorder, which is almost always associated with EBV.  Location of involvement can range from peripheral blood to bone marrow, spleen, and, liver.  Any organ can be involved.
Immunophenotypic Expression Pattern
Marker
Comment
Positive
Surface negative.  Cytoplasmic CD3ε positive.
Positive
TIA-1
Positive
Positive
References
Hematopathology. [edited by] Jaffe, ES. 1st. ed. Elsevier, Inc. © 2011.
Organ Systems, Lymph Node, Gastrointestinal, WHO Classification

Enteropathy-Associated T-cell Lymphoma

Immunophenotypic Expression Pattern
Marker
Comment
Positive
Positive
Negative
Negative
Positive
Negative (+ in a subset)
Negative
EBV (EBER)
Negative
Positive
Perforin
Positive
TIA-1
Positive
Variable.  Usually has at least some subset expression (varying intensity).
Negative
Negative
Negative
References
Parker, A., et. al.  “Best Practice in Lymphoma Diagnosis and Reporting.”  British Committee for Standards in Haematology, Royal College of Pathologists.  April, 2010.
 
Hematopathology. [edited by] Jaffe, ES. 1st. ed. Elsevier, Inc. © 2011.  pp. 289-91.