Category Archives: Bone Marrow

Organ Systems, Bone Marrow, Lymph Node, WHO Classification

Intravascular Large B-Cell Lymphoma

The B-cell population is predominately confined to the lumen of blood vessels.  The IHC immunophenotype may be similar to other DLBCLs and may have either a germinal center or non-germinal center immunophenotype.  There are several important characteristics.
Immunophenotypic Expression Characteristics
Marker
Comment
Negative (pan T-cell marker)
Positive
Co-expression may be seen on ~38% of the lymphoma cells.
Co-expression may be seen on ~13% of the lymphoma cells.
Variable.  Usually positive in CD10 negative cases.
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.
Organ Systems, Bone Marrow, Lymph Node, WHO Classification

Primary Effusion Lymphoma (PEL)

Primary Effusion Lymphoma (PEL) is a rare form of DLBCL associated with HIV infection.
Immunophenotypic Expression Pattern
Marker
Comment
Negative
Variable (often negative)
Positive
Positive
Positive
EBV (EBER)
Positive (majority of cases)
HHV-8
Positive
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, Bone Marrow, Lymph Node, WHO Classification

Chronic Lymphoproliferative Disorders of NK Cells

This is considered a provisional entity by the WHO classification in 2008.   In many ways this entity is similar clinically to T-LGL leukemia, but there are no rearrangements of immunoglobulin or T-cell receptors since the cells are NK cells.
Characteristic Immunophenotypic Profile
Marker
Comment
Surface CD3 negative.  Cytoplasmic CD3ε is often positive.
Usually weak expression
TIA-1
Positive
Positive
+/- May show diminished of loss of expression.
+/- May show diminished of loss of expression.
CD57
+/- May show diminished of loss of expression.
May show aberrant uniform expression.
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, 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, 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, Bone Marrow, WHO Classification

T-Cell Prolymphocytic Leukemia (T-PLL)

T-PLL is an aggressive T-cell leukemia composed of small to medium-sized post-thymic T-cells, which usually have a nucleolus (Up to 25% of cases may not have visible nucleoli).  Most patients will have generalized lymphadenopathy in addition to hepatosplenomegaly.  Up to 20% of cases will have skin involvement.
Charateristic Immunophenotypic Profile
 
Stain
Comment
Negative
Negative
Positive
Positive
Positive
CD4+/CD8-
CD4+/CD8+
CD4-/CD8+
~60% of cases
~25% of cases
~15% of cases
TCL1
Positive
References
Hematopathology. [edited by] Jaffe, ES. 1st. ed. Elsevier, Inc. © 2011.
Organ Systems, Bone Marrow, WHO Classification

T-cell Large Granular Lymphocytic Leukemia (T-LGL)

T-LGL leukemia represents only 2-3% of mature lymphocytic leukemias.  Classically patients present with neutropenia and splenomegaly.  Most patients don’t die from the leukemia itself, but accompanying diseases/cytopenias.  The peripheral blood LGL count is usually between 2-20x10e9/L.  THere is a significant gray-zone of uncertainty between what constitutes a benign population of LGLs and a neoplastic process (possibly an immune response that turns neoplastic??).
Features
  • Pathophysiology is NOT well understood
  • STAT3 mutated in approximately 1/3rd of cases (rarely STAT5B)
  • LGL count >2,000/μL (cases with <2,000/μL can be diagnosed if all other criteria are consistent with T-LGL leukemia
    • “All other criteria” are not well-described
  • Cases that resemble T-LGL but lack surface CD3 (sCD3) are classified in the NK-cell disorders.
Characteristic Immunophenotype
Stain
Comment
Positive
Usually Negative.  A subset of cases may express CD4.  CD4 + cases have been associated with an underlying malignancy  (~30% of cases).
+/- (May have diminished or lost expression)
+/- (May have diminished or lost expression)
Usually Positive
Granzyme_B
Usually Positive
TIA-1
Positive
CD57
Positive (>80% of cases)
Usually negative
References
Swerdlow SH, Campo E, Harris, NL, Jaffe ES, Pileri SA, Stein H, Thiele J (Eds):  WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues (Revised 4th edition). IARC: Lyon 2017
 
Hematopathology. [edited by] Jaffe, ES. 1st. ed. Elsevier, Inc. © 2011.