Lymphomas, B-Cell - B-Cell Lymphomas

Key Points

Double- and triple-hit lymphomas

B-cell lymphomas with two recurrent chromosomal breakpoint aberrations are referred to in the WHO classification as double-hit lymphomas and usually involve the MYC oncogene in association with the BCL2 translocation, although other translocation associations with MYC occur (eg, BCL6). If three translocations(eg, MYC, BCL2 and BCL6) are present, these lymphomas are referred to as triple-hit lymphomas; however they are rare. Histologically aggressive lymphomas in adults with coexpression of CD10, bcl6, and bcl2, with a high Ki67 proliferation index or those that have unusual clinical features (such as peripheral blood involvement) may be worked up to exclude a diagnosis of double- or triple-hit lymphomas. These lymphomas are often placed in the category of B-cell lymphoma unclassifiable with features intermediate between DLBCL (diffuse large B-cell lymphoma) and Burkitt lymphoma (WHO 2008). It is important to identify these lymphomas as they tend to manifest aggressive behavior and respond poorly to traditional chemotherapy. 

See table below for breakpoints used to identify double- or triple-hit lymphomas

Diagnosis

Indications for Testing

• Most common presentation for lymphoma is adenopathy with or without fever, also night sweats and fatigue

Laboratory Testing

• See the Lymphoma Phenotyping algorithm for specific test ordering recommendations
• Initial testing involves the following
  • CBC with peripheral smear
  • Liver chemistries
  • Lactate dehydrogenase (LD)
  • Serum uric acid, potassium, calcium, phosphorus
  • HIV for at-risk patients
• Immunophenotyping to identify the lymphoid proliferation malignancy and to categorize lymphoma type
  • May also be performed on bone marrow
• Testing prior to treatment with immunosuppressive therapies
  • HBV – surface antigen and core antibodies for all patients considering rituximab
    • Also include HBV e antigen testing for patients with relevant risk factors
  • HCV – for high-risk patients considering rituximab
  • CMV – PCR quantitative

Histology

• Follow-up testing with bone marrow biopsy
  • ≥2 cm specimen length
  • Classified as involved or not
  • Flow cytometry testing and immunoperoxidase staining of tissue for specific B-cell antigens or clonality with kappa and lambda light-chain staining
• B-cell clonality studies
  • Locate clonal rearrangements of the immunoglobulin gene in B-cell malignancies
  • Provide information regarding prognosis and treatment recommendations
  • Identify specific molecular translocations that characterize specific NHL subtypes
  • Translocation characterizations
    • Follicular lymphoma – BCL2 t(14;18)(q32;q21)
    • Burkitt lymphoma – MYC  t(8;14), t(2;8), t(8;22)
    • Mantle cell lymphoma – BCL1 (CCND1)  t(11;14)(q13;q32)
    • Diffuse large B-cell lymphoma (DLBCL) – BCL6 and BCL2 rearrangement
    • B-cell lymphoma unclassifiable with features intermediate between DLBCL (diffuse large B-cell lymphoma) and Burkitt lymphoma (WHO 2008) – refer to Key Points for double- and triple-hit lymphomas
    • ALL translocations – refer to acute lymphoblastic leukemia
    • NHL – fluorescence in situ hybridization (FISH) testing for t(11;14), t(14;18) and MYC translocations, ALK rearrangement, and BCL6 translocations
    • Mucosa-associated lymphoid tissue (MALT) – molecular testing for t(11;14), t(14;18)
    • Hairy cell leukemia – BRAF V600E mutation testing
  • Other testing
    • EBV genome presence in immune suppression (eg, post transplantation) – in situ hybridization testing
    • Kappa and lambda light-chain clonality in situ hybridization
    • Other testing may be necessary to differentiate B-cell from T-cell NHL (eg, ALK by FISH)
    • BRAF V600E – present in most classic hairy cell leukemias
• Immunohistochemistry – useful in conjunction with phenotyping for NHL cell type
  • Most commonly used stains include cyclin D1, Pax-5, Ki-67, MUM1-IRF4, HHV8, EBV, ALK-1, CD3, CD5, CD10 (CALLA), CD19, CD20, CD21 (dendritic cell), CD22, CD23, CD25, CD30 (Ki-1), CD79A, CD138 (Syndecan-1), BCL-2, kappa and lambda light chains, TRAP, and TdT
  • Other available stains – BOB-1, Bax, caspase-3, CD15, CD43, CD45, CD45RA-MT2, CD45RO, CD74, c-Myc, DBA.44, and Oct 2

Prognosis

• International Prognostic Index scoring system
  • Based on pretreatment clinical factors of age (≤60 years); Ann Arbor tumor stage (I or II); number of extranodal sites (≤1); Eastern Cooperative Oncology Group (ECOG) performance status (0 or 1); and serum LD (≤1 times normal) – all scored as 0
  • Patients placed in 4 risk groups
  • Limited usefulness in follicular lymphoma, mantle cell lymphoma, NK lymphoma, nasatype, hepatosplenic lymphoma and enteropathy-type lymphoma
• Follicular Lymphoma International Prognostic Index scoring system
  • 5 risk factors (scored as 1)
    • IgG <12 g/dL
    • LD >normal
    • Ann Arbor tumor stage (III or IV)
    • >4 nodal sites
    • Age >60 years
  • 0-1 risk factors – low risk (5-year survival 90%)
  • 2 risk factors – intermediate risk (5-year survival 78%)
  • 3 risk factors – high risk (5-year survival 53%)
• All prognostic indices may change in the future as the IPI and FLIPI indices were developed before immunotherapy
• Genetic mutations (cytogenetics)
  • Follicular lymphoma
    • Adverse prognosis associated with del 17p, trisomy 12 and abnormalities of 6p
  • Diffuse large B-cell lymphoma (DLBCL)
    • Better prognosis associated with t(14;18)
    • Adverse prognosis with MYC oncogene; BCL2 gene, p53(+)
  • Follicular and DLBCL
    • Dismal outcomes for 8q24/MYC in association with 18q21/BCL2 or 3q27/BCL6
  • Double-hit and triple-hit lymphomas
    • Tend to manifest aggressive behavior and respond poorly to traditional chemotherapy
    • Refer to Key Points for double- and triple-hit lymphomas
  • CLL
    • CD38 and ZAP-70 – mutation status correlates inversely with prognosis

Differential Diagnosis

• Lymphomas
  • T/NK-cell lymphoma
  • Hodgkin lymphoma
• Reactive lymphocytosis
• Sarcoidosis
• Other malignancy
  • Head and neck cancer
  • Metastatic
• Infections
  • EBV
  • M. tuberculosis
  • Bartonella spp
  • Human herpesvirus 8
  • CMV
  • HIV
  • Toxoplasma gondii
  • Treponema pallidum
  • Babesia microti
  • Fungal disease

Monitoring

Clinical Background

B-cell non-Hodgkin lymphomas (NHL) represent a heterogenous group of malignancies of the lymphoid system.

Epidemiology

• Incidence – represents 80-85% of the cases of NHL diagnosed annually
  • >66,000 new cases of NHL diagnosed in 2008
• Age – peaks in 60s
• Sex – M<F (minimal)

WHO Classification of Mature B-Cell Neoplasms (2008)

• Chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL)
• B-cell prolymphocytic leukemia
• Splenic marginal zone lymphoma (MZL)
• Hairy cell leukemia
• Splenic lymphoma/leukemia, unclassifiable
• Lymphoplasmacytic lymphoma
• Heavy chain diseases
• Plasma cell neoplasms
• Extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT)
• Nodal MZL
• Follicular lymphoma
• Primary cutaneous follicle center lymphoma
• Mantle cell lymphoma
• Diffuse large B-cell lymphoma (DLBCL), NOS (not otherwise specified)
• T-cell/histiocyte-rich large B-cell lymphoma
• Primary DLBCL of the central nervous system
• Primary cutaneous DLBCL, leg type
• Epstein-Barr virus (EBV)-positive DLBCL of the elderly
• DLBCL associated with chronic inflammation
• Lymphomatoid granulomatosis
• Primary mediastinal (thymic) large B-cell lymphoma
• Intravascular large B-cell lymphoma
• ALK-positive large B-cell lymphoma
• Plasmablastic lymphoma
• Large B-cell lymphoma arising in HHV8-associated multicentric Castleman disease
• Primary effusion lymphoma
• Burkitt lymphoma
• B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and Burkitt lymphoma
• B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and classical Hodgkin lymphoma

Risk Factors

• Presence of autoimmune diseases, iatrogenic or acquired immune deficiency
  • Sjögren syndrome
  • Celiac disease
  • Rheumatoid arthritis
  • Post-transplant immunosuppression
  • Immunosuppressive drugs
  • HIV infection
• Inherited disorders
  • Chédiak-Higashi syndrome
  • Common variable immune deficiency
  • Wiskott-Aldrich syndrome
• Chronic infection
  • EBV – diffuse large B-cell lymphoma (DLBCL) of the CNS
  • Helicobacter pylori – gastric extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) lymphoma
  • Hepatitis C (HCV) – lymphoplasmacytic lymphoma, marginal zone lymphoma (MZL), follicular lymphoma
  • Human herpes virus 8 (HHV8) – primary effusion lymphoma
  • Hepatitis B (HBV) – risk of reactivation with immunosuppressive treatment regimens (eg, rituximab)
  • Cytomegalovirus (CMV) – high risk of reactivation with immunosuppressive treatment regimens (eg, alemtuzumab)

Clinical Presentation of Selected Lymphoma Subtypes (based on WHO classification)

CLL/SLL

Incidence – 2-6/100,000; 6-7% of NHL Age – median >60 years Sex – M>F, 1.5-2:1 Symptoms – adenopathy hepatosplenomegaly; some patients present with autoimmune hemolytic anemia, fatigue, infections Prognosis – good; indolent tumor

Splenic marginal zone lymphoma (MZL)

Incidence – rare Age – >50 years Sex – M:F, equal Symptoms – splenomegaly, often with autoimmune thrombocytopenia Prognosis – good; indolent adenopathy

Hairy cell leukemia

Incidence – rare; ≤2% of NHL Age – median 50 years Sex – M>F, 5:1 Symptoms – peripheral adenopathy rare; splenomegaly, fatigue, weakness, fever, bleeding, infections Prognosis – good; with treatment, disease may remain silent for years

Lymphoplasmacytic lymphoma

Incidence – rare; 3/1,000,000 Age – median 65 years Sex – M>F (minimal) Higher risk if patient has monoclonal gammopathy of undetermined significance Symptoms – fatigue, malaise, hepatosplenomegaly, adenopathy, hyperviscosity syndrome (~30%) Prognosis – usually moderately good; indolent tumor

Extranodal marginal zone lymphoma (MZL) of mucosa-associated lymphoid tissue (MALT)

Incidence – 8-10% of NHL; increased risk with chronic Helicobacter infection Age – median 60 years Sex – M<F (minimal) Ethnicity – increased prevalence in northeast Italy and Middle East Symptoms – related to organ location Prognosis – favorable; indolent tumor

Nodal MZL (+/- monocytoid B-cells)

Incidence – rare Age – median 60 years Sex – M:F, equal Symptoms – lymphadenopathy Prognosis – good; can be predicted from Follicular Lymphoma International Prognostic Index

Follicular lymphoma

Incidence – 20-25% of NHL Age – 50s-60s; rare in children Sex – M<F, 1:1.7 Ethnicity – higher incidence in U.S. and western Europe Symptoms – lymphadenopathy extranodal disease, bone marrow involvement (other sites uncommon) Prognosis – reasonably good but disease tends to relapse; can be predicted from International Prognostic Index

Mantle cell lymphoma

Incidence – 6-10% of NHL Age – median is 60 years Sex – M>F, 2:1 Symptoms – adenopathy, splenomegaly, bone marrow involvement Prognosis – poor; aggressive tumor

Diffuse large B-cell lymphoma (DLBCL)

Incidence – 25-31% of NHL Age – median is 60 years Sex – M>F (minimal) Symptoms – rapidly enlarging tumor at nodal or extranodal site Prognosis – poor, aggressive tumor

Primary effusion lymphoma

Incidence – rare; occurs in HIV patients and universally associated with HHV8 Age – 30s-40s Sex – M>F Symptoms – dyspnea, abdominal distention Prognosis – poor; aggressive tumor

Burkitt lymphoma

Incidence – rare in U.S., endemic in Africa; significant risk with EBV Age Children – endemic form Individuals in 30s – nonendemic form Symptoms – lesions commonly found in jaw and face Prognosis – poor; highly aggressive tumor

• Plasma cell neoplasms – plasmacytoma (plasma cell dyscrasias)
  • For incidence, age, sex, symptoms and prognosis, see plasma cell dyscrasias

Indications for Laboratory Testing

• Tests generally appear in the order most useful for common clinical situations
• Click on number for test-specific information in the ARUP Laboratory Test Directory

Click the plus sign to expand the table of additional tests.

Test Name and Number	Comments
B-Cell CD20 Expression 0092099 Method: Flow Cytometry
B-Cell Clonality Screening (IgH and IgK) by PCR 2006193 Method: Polymerase Chain Reaction/Capillary Electrophoresis
Chromosome Analysis, Bone Marrow 2002292 Method: Giemsa Band	Identify neoplastic populations in marrow
B Cell Specific Octamer Binding Protein-1 (BOB-1) by Immunohistochemistry 2003442 Method: Immunohistochemistry
Caspase-3 by Immunohistochemistry 2003496 Method: Immunohistochemistry
CD15, Leu M1 by Immunohistochemistry 2003529 Method: Immunohistochemistry
CD43, L60 (Leu 22) by Immunohistochemistry 2003568 Method: Immunohistochemistry
CD45 by Immunohistochemistry 2003574 Method: Immunohistochemistry
Hairy Cell Leukemia, DBA.44 by Immunohistochemistry 2003860 Method: Immunohistochemistry
Octamer Transcription Factor-2 (Oct 2) by Immunohistochemistry 2004061 Method: Immunohistochemistry
Hepatitis B Virus Core Antibodies (Total) 0020091 Method: Qualitative Chemiluminescent Immunoassay	Identify HBV status if considering rituximab therapy
Hepatitis B Virus Surface Antigen, Confirmation 0020128 Method: Chemiluminescent Immunoassay	Identify HBV status if considering rituximab therapy
Hepatitis C Virus Antibody by CIA 2002483 Method: Qualitative Chemiluminescent Immunoassay	Screen for hepatitis C virus (HCV) infection in at-risk individuals Screens for IgG antibodies to HCV
Cytomegalovirus, Quantitative PCR 0051813 Method: Quantitative Polymerase Chain Reaction	Preferred test for posttransplant surveillance Quantifies CMV viral load in plasma
Human Immunodeficiency Virus Types 1 and 2 (HIV-1, HIV-2) Antibodies with Reflex to HIV-1 Antibody Confirmation by Western Blot 2005377 Method: Qualitative Chemiluminescent Immunoassay/Qualitative Western Blot	Use for at-risk patients

Diagnostic Algorithm

  Lymphoma Leukemia Phenotyping Testing Algorithm