Lymphoid Neoplasms. Sylvie Freeman Department of Clinical Immunology, University of Birmingham

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Lymphoid Neoplasms Sylvie Freeman Department of Clinical Immunology, University of Birmingham

Incidence of Haematological Malignancies UK2001 (CRUK) Malignancy New Cases All Cancers 271,000 Leukaemia 6,760 (2%) Non-Hodgkin s Lymphoma 9,280 (3%) Hodgkin s Disease 1,430 (<1%) Multiple Myeloma 3,570 (1%)

Overview of Lymphoma neoplasms of lymphoid origin, typically causing lymphadenopathy leukemia vs lymphoma lymphomas viewed as clonal expansions of lymphocyte arrested at a certain stage of development and transformed into a malignant cell types of non- Hodgkin s lymphoma reflect the developmental stages of lymphocytes. 85% of NHL are of B cell origin

B +TdT +HLA-DR Stem Cell T B cell T cell Precursor Pro B TdT+ CD19+ Pre B Bone Marrow Bone CD19+ Marrow CD22+ CD20+/- CD10+/- Thymus TdT+ CD4- CD8- TCR Pre thymic Cortical Thymocyte TCR Medullar Thymocyte T TdT+ CD4+ TdT+ CD4+ CD8+ TdT+ CD8+ Mature Mature B CD20+ CD22+ CD19+ CD10+/- Memory Naive Centroblast Centrocyte Plasma cell Peripheral Blood & 2ry Lymphoid Organs TdT+ CD4- CD8- CD4- CD8- Mature T cell T cell CD4+ Helper T CD8+ Cyto toxic T Fig. B and T cell MaturationPathway

Types of Lymphoid neoplasms Precursor B- and T- cell (lymphoblastic leukaemia/lymphoma) Mature B-cell neoplasms (includes NHLs, chronic leukaemias, plasma cell dyscrasias) Mature T-cell and NK-cell neoplasms (includes NHLs, chronic leukaemias) (Hodgkin lymphoma)

B-cell development stem cell lymphoid precursor progenitor-b LBL, ALL pre-b immature B-cell CLL MCL mature naive B-cell germinal center B-cell DLBCL, FL, BL, HL memory B-cell MZL CLL MM plasma cell

Mantle zone lymphoma Follicular lymphoma Burkitt s lymphoma Small lymphocytic lymphoma Waldenström s macroglobulinemia Sézary syndrome Mycosis fungoides Peripheral T cell lymphoma

The challenge of lymphoma classification Biologically rational classification Diseases that have distinct morphology immunophenotype genetic features clinical features Clinically useful classification Diseases that have distinct clinical features natural history prognosis treatment

WHO Classification (2001) B-cell neoplasms Precursor B-cell neoplasm Precursor B-lymphoblastic leukemia/lymphoma (precursor B-cell acute lymphoblastic leukemia) Mature (peripheral) B-cell neoplasms B-cell chronic lymphocytic leukemia/small lymphocytic lymphoma B-cell prolymphocytic leukemia Lymphoplasmacytic lymphoma Splenic marginal zone B-cell lymphoma (with or w/o villous lymphocyt es) Hairy cell leukemia Plasma cell myeloma/plasmacytoma Extranodal marginal zone B-cell lymphoma of mucosa- associated lymphoid tissue type Nodal marginal zone B-cell lymphoma (with or w/o monocytoid B cells) Follicular lymphoma Mantle cell lymphoma Diffuse large B-cell lymphoma Mediastinal large B-cell lymphoma Primary effusion lymphoma Burkitt's lymphoma/burkitt's cell leukemia T- and NK-cell neoplasms Precursor T-cell neoplasm Precursor T-lymphoblastic lymphoma/leukemia (precursor T- cell acute lymphoblastic leukemia) Mature (peripheral) T-cell neoplasms T-cell prolymphocytic leukemia T-cell granular lymphocytic leukemia Aggressive NK-cell leukemia Adult T-cell lymphoma/leukemia (human T-cell lymphotropic virus type I positive) Extranodal NK/T-cell lymphoma, nasal type Enteropathy type T-cell lymphoma Hepatosplenic gammadelta T-cell lymphoma Subcutaneous panniculitis-like T-cell lymphoma Mycosis fungoides/sezary syndrome Anaplastic large cell lymphoma, T/null-cell, primary cutaneous type Peripheral T-cell lymphoma, not otherwise characterized Angioimmunoblastic T-cell lymphoma Anaplastic large cell lymphoma, T/null-cell, primary systemic type

B-Cell Lymphoma Precursor lymphoblastic lymphoma/leukemia Mature Small lymphocytic lymphoma/leukemia Lymphoplasmacytic lymphoma Marginal Zone Lymphoma Follicular lymphoma Mantle cell lymphoma Diffuse large B cell Burkitt s lymphoma Hairy cell leukemia Plasma cell myeloma

T-Cell Lymphoma Precursor lymphoblastic lymphoma/leukemia Mature Peripheral T (unspecified) T-cell large granular lymphocytic leukaemia NK leukaemia Anaplastic large cell T/null Cutaneous anaplastic large cell T/null Mycosis Fungoides/Sezary syndrome Adult T-cell lymphoma/leukemia HTLV-1 + Enteropathy-type intestinal Hepatosplenic gamma delta Angioimmunoblastic

Non-Hodgkin lymphoma Incidence Diffuse large B-cell lymphoma Follicular NHL Other NHL

Pillars of WHO/REAL Classification Cell of origin Cell morphology Immunophenotyping Genotyping Clinical picture Abandon the use of indolent aggressive highly aggressive

Prognostic Indicators Histopathologic Type Grades within subtypes e.g. follicular lymphoma Variants within subtypes e.g. Blastoid mantle cell Biology Proliferation fraction Oncogenes, tumor suppressor genes, MDR Clinical Parameters Stage and bulk of disease International prognostic index

WHO Classification Indolent Aggressive Very Aggressive CLL/SLL Lymphoplasmacytoid/WM HCL Splenic marginal zone lymphoma Marginal zone lymphoma Extranodal (MALT) Nodal Follicular NHL (grade I-II) PLL Plasmacytoma/ multiple myeloma Mantle cell NHL Follicular NHL (grade III) DLBCL High-grade B-cell lymphoma/burkitt s-like PrecursorBlymphoblastic lymphoma/leukemia Burkitt s lymphoma/ B-cell acute leukemia Plasma cell leukemia

Category Survival of untreated patients Curability To treat or not to treat Non- Hodgkin lymphoma Indolent Years Generally not curable Aggressive Months Curable in some Generally defer Rx if asymptomatic Treat Very aggressive Weeks Curable in some Treat Hodgkin lymphoma All types Variable months to years Curable in most Treat

Risk factors for NHL Immune suppression Inherited immunodeficiencies organ transplant (cyclosporine) AIDS increasing age DNA repair defects ataxia telangiectasia xeroderma pigmentosum

Risk factors for NHL Chronic inflammation and antigenic stimulation Helicobacter pylori inflammation, stomach Chlamydia psittaci inflammation, ocular adnexal tissues Sjögren s syndrome Viral causes EBV and Burkitt s lymphoma HTLV-I and T cell leukemia-lymphoma Hepatitis C and SLVL

Clinical Features Variable severity: asymptomatic to extremely ill time course: evolution over weeks, months, or years Systemic manifestations (B symptoms) fever, night sweats, weight loss, anorexia, pruritis Local manifestations lymphadenopathy, splenomegaly most common, any tissue potentially can be infiltrated Cytopenias

Clinical Features Extranodal primary - more common in high-grade lymphoma. Lymphadenopathy may fluctuate or spontaneously remit, especially in low-grade lymphomas. B symptoms more common in high-grade lymphomas. Haematogenous spread of disease, with no predictable pattern.

Other complications of lymphoma bone marrow failure (infiltration) CNS infiltration immune hemolysis or thrombocytopenia neutropenia in LGL leukaemias immunosuppression eg Igs (chronic LPDs), T cell (Hodgkin s or post fludarabine) compression of structures (eg spinal cord, ureters) by bulky disease pleural/pericardial effusions, ascites

Types of Lymphoma Indolent (low grade) Life expectancy in years, untreated 85-90% present in Stage III or IV Incurable (except? by allogenic SCT) Intermediate eg Mantle cell NHL Aggressive (high grade) Life expectancy in weeks, untreated Potentially curable

Epidemiology Indolent lymphomas are rare in young people and increase in incidence with age. High grade lymphoma is less age related, and is among most common cancers affecting the young. Burkitt s and lymphoblastic lymphoma are common in adolescents. AIDS patients develop aggressive, high grade lymphomas (Burkitt s, Burkitt s -like).

Diagnosis of NHL Excisional biopsy needed to show nodal architecture (follicular vs diffuse). Immunophenotyping - immunohistochemistry of tissue sections) - flow cytometry (blood / BM / biopsy) Cytogenetics (inlcuding FISH, molecular studies) Ig / TCR gene rearrangement studies (clonality)

Mantle Cell Lymphoma Pax-5 t(9;14) B-CLL Small Lymphocytic p53? Bcl-1 t(11;14) Lymphoplasmacytic CD5- B Cells CD5+ B Cells Mantle Zone Germinal Center Marginal Zone Bcl-2 t(14;18) Follicular Lymphoma Bcl-6 t(2;3)? p53, c-myc, EBV t(8;14) t(8;22) t(2;8) p53 Diffuse Large Cell Lymphoma Burkitt s Lymphoma Richter s Syndrome Bcl-10 t(1;14) Marginal Zone Lymphoma (MALT) Molecular pathogenesis of B-cell lymphomas

Staging Workup Requires CT scans of chest, abdomen and pelvis Bone marrow biopsy and aspirate (Lumbar puncture) eg AIDS lymphoma lymphoblastic lymphoma High grade lymphoma with positive marrow

Staging of lymphoma (Ann Arbor) Stage I Stage II Stage III Stage IV A: absence of B symptoms B: fever, night sweats, weight loss E: extranodal

International Prognostic Index (IPI) Patients of all ages Risk factors Age >60 years Performance status (PS) 2 4 Lactate dehydrogenase (LDH) level Elevated Extranodal involvement >1 site Stage (Ann Arbor) III IV Patients 60 years (age-adjusted) PS 2 4 LDH Elevated Stage III IV

Patients (%) Diffuse Large B-Cell Lymphoma (DLCL): OS 100 80 60 IPI 0-1 40 IPI 2-3 20 P<0.001 IPI 4-5 0 0 1 2 3 4 5 6 7 8 Year

Strategies for Improving Outcome for Aggressive NHL Monoclonal antibodies (MoAbs) Rituximab (anti-cd20) Combination with chemotherapy Dose intensification High-dose chemotherapy/asct Growth factor incorporation

Treatment for advanced indolent NHLs Deferred therapy Single alkylating agent Radiation therapy Combination chemotherapy Biological therapy MoAbs IFN Transplant autologous allogenic Purine analogues

MoAbs for Lymphoid malignancies MoAb Antigen Type Lymphoma rituximab CD20 Chimeric B cells epratuzumab CD22 Humanized B cells CD30 Humanized anaplastic / Hodgkin CD25 Humanized adult T-cell leukaemia campath CD52 Humanized CLL, T-PLL

Proposed Mechanisms of Action for MoAbs Immune Antibody-dependent cell-mediated cytotoxicity (ADCC) Complement-dependent cytotoxicity (CDC) Apoptosis +/- radioactive labels (eg Iodine, Yttrium)

Immunophenotyping Differentiation of normal and malignant haematological populations Uses antibody recognition of surface / intracellular antigens Important for - diagnosis / prognostic evaluation - monitoring treatment response (MRD) - identification of suitable targets for antibody therapy Flow cytometry v Immunohistochemistry of tissue sections

CD20 Expression in B-Cell Malignancies Hairy cell DLBCL Burkitt s lymphoma Marginal zone Follicular LP/Waldenström s Mantle cell CLL/PLL CLL 0 100 200 300 400 500 Mean channel fluorescence

Immunophenotyping Flow cytometry Disadvantages (compared to immunohistochemistry) No visualisation of tissue architecture Poor yield of cells from sclerotic and some packed samples Misses rare neoplastic cells eg Hodgkins Sampling differences in patchy neoplastic infiltrates

Immunophenotyping Diagnosis Lineage classification myeloid v lymphoid (B or T or NK) Maturation classification

Immunophenotyping B cell LPD Light chain restriction (clonality) Aberrant pattern of antigens compared with normal subsets T cell LPD Subset restriction eg CD4 or CD8 ( but need TCR gene clonality) Aberrant pattern of antigens compared with normal subsets

Lymphoproliferative Panel Tube FITC PE PERCP/APC 1 IgG control IgG control IgG control 2 CD7 CD56 CD3 3 CD4 CD8 CD3 4 kappa lambda CD19APC 5 CD20 CD5 CD19APC 6 TCRgammadelta CD2 CD3 7 CD79b CD23 CD19APC 8 CD19 CD38 CD45 9 CD10 CD19 CD34 10 CD103 CD22 CD19APC

Notable Subtypes of Lymphoma

Follicular lymphoma most common type of indolent lymphoma usually widespread at presentation not curable (some exceptions) cell of origin: germinal center B-cell - centrocytes / centroblasts - expression of CD10 - IgV mutations (and signs of ongoing mutations) - BUT maintain high BCL-2 [t(14;18)]

Mantle cell NHL Intermediate usually widespread at presentation 20-30% longterm survival cell of origin: resemble follicle mantle cells (mature naïve B cells) - IgV either not mutated (90% of cases) or only very few mutations - positive for CD5 (like CLL) - but lack CD23 (unlike CLL) - t(11;14) - overexpression of cyclin D1

Lymphoplasmacytoid /Waldenstrom s Low grade Spleen, bone marrow, lymph nodes IgM paraprotein - hyperviscosity symptoms (10-30% of patients) - autoantibody or cryoglobulin activity cell of origin: may originate from B cells that have bypassed germinal centre - IgVH restricted, somatically mutated, predominantly CD27neg, IgM+IgD+ CD10neg CD5neg

Marginal zone lymphomas Usually localised extranodal (30% disseminated) Associated with 1) autoimmune diseases eg Sjorgen s, Hashimoto s 2) infections eg H Pylori - gastric MALT NHL Hep C - SLVL Can transform to DLBCL cell of origin: marginal zone (memory) B cell - IgM (absence of IgD) - typically have mutated IgV genes with ongoing mutations CD10neg CD5neg

Hairy cell Leukaemia low grade, rare Splenomegaly, pancytopenia, Hairy cells in spleen red pulp, blood, bone marrow (rarely LAD) Long-term survival with purine analogues Immune dysfunction, includes vasculitis cell of origin:? - has activation markers CD25, CD11c, CD103-40% of HCL express multiple surface Ig isotypes - on-going somatic mutation but lacks other features of germinal centre cells - gene profiling - more related to memory B cells

Chronic Lymphocytic Leukaemia /SLL Most prevalent leukaemia (30% of all leukaemias) Variable clinical course asymptomatic for many years v aggressive 5-10% transform to high grade (Richter s) - poor prognosis Hypogammaglobulinaemia Autoimmune cytopenias cell of origin:? - 50% CLLs - unmutated IgVH genes (poor prognosis) - (50% CLLs - mutated IgVH genes (better prognosis) however both types - common gene expression signature (but different from other lymphomas /leukaemias) - CD5+CD23+ weak surface Ig / BCR

Diffuse large B-cell lymphoma (DLBCL) most common type of aggressive lymphoma usually symptomatic extranodal involvement is common curable in ~ 40% cell of origin: - immunophenotypic and genetic features of B cells and B cell subsets but often incomplete / aberrant

AIDS Lymphoma Aggressive lymphomas of B cell origin. risk in HIV+ despite HAART Burkitt s, Burkitt s-like, and DLBCL. Primary CNS lymphoma/ Primary Effusion lymphoma Hodgkins Treatment often limited by immunocompromised status eg rituximab benefit offset by infections. Prognosis improved with HAART therapy.

Mycosis Fungoides / Sezary s Malignancy of helper T cells (Th2 response) CD4+ often CD7neg (CD25neg) Affinity for skin. Can be treated with electron beam therapy, PUVA, retinoids, IFN Sezary s when systemic (blood, lymph nodes)

Hodgkin lymphoma Lymphocyte predominant - B cell neoplasm (CD20+) with features of germinal centre origin (rearranged Ig, somatic mutations) Classical Hodgkin s neoplastic cells rearranged, mutated Ig genes no or little B cell immunphenotype, gained CD30, CD15 Reed-Sternberg cells (or RS variants) in the affected tissues most cells in affected lymph node are polyclonal reactive lymphoid cells, not neoplastic cells

RS cell and variants classic RS cell lacunar cell popcorn cell (mixed cellularity) (nodular sclerosis) (lymphocyte predominance)

A possible model of pathogenesis transforming event(s) loss of apoptosis EBV? germinal centre B cell RS cell cytokines inflammatory response