1 History of Lymphoma Classification.- 1.1 Introduction.- 1.2 The Kiel Classification.- 1.3 The REAL Classification Proposal.- 1.4 The WHO Classification.- References.- 2 Current Status of Lymphoma Classification.- 2.1 Introduction.- 2.2 Small- and Large-Cell Versus Low- and High-Grade.- 2.3 Primary Versus Secondary Lymphoma.- 2.4 Definition of Immunocytoma and Its Border with Marginal Zone B-Cell Lymphoma.- 2.5 Indistinct Border Between Nodal Marginal Zone B-Cell Lymphoma and Follicular Lymphoma with Marginal Zone Differentiation.- 2.6 Grading of Follicular Lymphoma.- 2.7 Distinction Between Diffuse Large B-Cell Lymphoma and Burkit’s Lymphoma: Reproducibility and Value of Subclassification.- 2.8 Problems in Reproducibly Recognizing Anaplastic Large-Cell Lymphoma and Lymphoblastic Lymphoma on Purely Morphological Grounds.- 2.9 Is Peripheral T-Cell Lymphoma, Unspecified a Distinct Clinicopathological Entity or a Catchall Term?.- 2.10 Neither the WHO nor the EORTC Classification of Cutaneous Lymphoma Covers Today’s Knowledge.- References.- 3 Epidemiology.- 3.1 Introduction.- 3.2 Statistical Data of the Kiel Lymphoma Registry.- 3.2.1 Age and Sex Distribution.- Malignant Lymphoma of Childhood.- References.- 4 Nodal B-Cell Lymphoma.- 4.1 Precursor B-Cell Lymphoblastic Leukemia.- 4.2 Peripheral B-Cell Lymphoma.- 4.2.1 Small-B-Cell Lymphoma.- 4.2.1.1 Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma.- 4.2.1.2 Lymphoplasmacytic Lymphoma — Partially Corresponding to Macroglobulinemia Waldenström.- 4.2.1.3 Hairy Cell Leukemia.- 4.2.1.4 Plasmacytoma.- 4.2.1.5 Nodal Marginal Zone B-Cell Lymphoma.- 4.2.1.6 Follicular Lymphoma.- 4.2.1.7 Mantle Cell Lymphoma.- 4.2.2 Large-B-Cell Lymphoma.- 4.2.2.1 Diffuse Large-B-Cell Lymphoma — Common Features.- 4.2.2.2 Diffuse Large-B-Cell Lymphoma — Morphological Variants.- 4.2.2.3 Diffuse Large-B-Cell Lymphoma — Clinical Variants.- 4.2.3 Burkitt’s Lymphoma.- References.- 5 Nodal and Leukemic NK/T-Cell Lymphoma.- 5.1 Precursor T-Lymphoblastic Leukemia/Lymphoma.- 5.2 Peripheral NK/T-Cell Lymphoma.- 5.2.1 Peripheral NK/T-Cell Lymphoma — Predominately Leukemic.- 5.2.1.1 T-Cell Chronic Lymphocytic/Prolymphocytic Leukemia.- 5.2.1.2 Adult T-Cell Leukemia/Lymphoma.- 5.2.2 Peripheral NK/T-Cell Lymphoma Predominately Nodal.- 5.2.2.1 Angioimmunoblastic T-Cell Lymphoma.- 5.2.2.2 Peripheral T-Cell Lymphoma, Unspecified.- 5.2.2.3 Mycosis Fungoides/Sézary’s Syndrome Secondary to the Lymph Node.- 5.2.2.4 Anaplastic Large-Cell Lymphoma (T and Null Types).- References.- 6 Extranodal Lymphoma.- 6.1 Introduction.- 6.2 Gastrointestinal Lymphoma.- 6.2.1 B-Cell Lymphoma.- 6.2.1.1 Extranodal Marginal Zone B-Cell Lymphoma of MALT.- 6.2.1.2 Intestinal Follicular Lymphoma.- 6.2.1.3 Multiple Lymphomatous Polyposis — Intestinal Mantle Cell Lymphoma.- 6.2.1.4 Diffuse-Large-B-Cell Lymphoma of Gastrointestinal Tract.- 6.2.1.5 Burkitt’s Lymphoma of the Gastrointestinal Tract.- 6.2.2 Primary Gastrointestinal T-Cell Lymphoma.- 6.2.2.1 Enteropathy-Type T-Cell Lymphoma.- 6.2.2.2 NK/T-Cell Lymphoma, Nasal Type.- 6.2.2.3 Anaplastic Large-Cell Lymphoma.- 6.3 Lymphoma of the Upper Aerodigestive Tract.- 6.3.1 Lymphoma of the Oral Cavity.- 6.3.2 Lymphoma of Waldeyer’s Ring and the Pharynx.- 6.3.3 Lymphoma of the Nasal Cavity and Paranasal Sinuses.- 6.3.3.1 B-Cell Lymphoma.- 6.3.3.2 Extranodal NK/T-Cell Lymphoma — Nasal Type.- 6.3.4 Lymphoma of the Larynx and Trachea.- 6.4 Malignant Lymphoma of the Major Salivary Glands.- 6.5 Lymphoma of the Eye, Lachrymal Glands, and Orbit.- 6.5.1 Lymphoma of the Conjunctiva, Eyelids, Lachrymal Glands, and Orbit.- 6.5.2 Lymphoma of the Uvea and Retina (Similar to CNS Lymphoma).- 6.5.3 Primary Lymphoma of the Eye, Lachrymal Glands, and Orbit.- 6.6 Lymphoma of the Mediastinum.- 6.6.1 Mediastinal (Thymic) Large-B-Cell Lymphoma.- 6.6.2 Extranodal Marginal Zone B-Cell Lymphoma of the Thymus.- 6.6.3 Mediastinal Involvement in Precursor T- or B-Cell Lymphoblastic Lymphoma.- 6.6.4 Mediastinal Involvement in Small-B-Cell Lymphoma.- 6.6.5 Mediastinal Involvement in Large-B-Cell Lymphoma Other Than Primary Mediastinal Large-B-Cell Lymphoma and Burkitt’s Lymphoma.- 6.6.6 Mediastinal Involvement in NK/T-Cell Lymphoma.- 6.7 Lymphoma of the Lung.- 6.7.1 Primary Lymphoma of the Lung.- 6.7.1.1 Extranodal Marginal Zone B-Cell Lymphoma of MALT.- 6.7.1.2 Primary Diffuse Large-B-Cell Lymphoma of the Lung.- 6.7.1.3 Primary Lung Intravascular Large-B-Cell Lymphoma.- 6.7.1.4 Large B-Cell Lymphoma Secondary to Liebow’s Lymphomatoid Granulomatosis.- 6.7.1.5 Primary Lung Plasmacytoma.- 6.7.1.6 Primary NK/T-Cell Lymphoma of the Lung.- 6.8 Lymphoma of the Pleura.- 6.8.1 Primary Lymphoma of the Pleura.- 6.8.1.1 Primary Effusion Lymphoma.- 6.8.1.2 Pyothorax-Associated Primary Lymphoma.- 6.8.2 Secondary Pleural Lymphoma.- 6.9 Lymphoma of the Heart.- 6.9.1 Primary Cardiac Lymphoma.- 6.10 Splenic Lymphoma.- 6.10.1 Primary Splenic Lymphoma or Lymphoma with a Splenic Predominance.- 6.10.1.1 Hairy Cell Leukemia.- 6.10.1.2 Splenic Marginal Zone Lymphoma.- 6.10.1.3 Primary Splenic Lymphoplasmacytic Lymphoma.- 6.10.1.4 Plasmacytoma.- 6.10.1.5 B-Prolymphocytic Leukemia.- 6.10.1.6 Large B-Cell Lymphoma of the Spleen.- 6.10.1.7 Hepatosplenic T-Cell Lymphoma.- 6.10.1.8 T-Cell Large Granular Lymphocytic Leukemia.- 6.10.1.9 Other Types of Lymphoma.- 6.10.2 Secondary Splenic Lymphoma.- 6.10.2.1 Small-B-Cell Lymphoma.- 6.10.2.2 Other Types of B-Cell Lymphoma.- 6.10.2.3 Peripheral NK/T-Cell Lymphoma.- 6.10.2.4 Precursor Cell Neoplasias: B- and T-Lymphoblastic Lymphoma.- 6.11 Lymphoma of the Liver.- 6.11.1 Primary Lymphoma of the Liver.- 6.11.1.1 Primary Lymphoma Presenting as a Tumorous Infiltrate of the Liver.- 6.11.1.2 Primary Hepatic Lymphoma Presenting as Severe Hepatic Disease.- 6.11.2 Secondary Lymphoma of the Liver.- 6.12 Lymphoma of the Breast, Reproductive, and Urinary Systems.- 6.12.1 Malignant Lymphoma of the Breast.- 6.12.1.1 Primary Lymphoma of the Breast.- 6.12.1.2 Secondary Lymphoma of the Breast.- 6.12.2 Malignant Lymphoma of the Uterus.- 6.12.2.1 Primary Uterine Lymphoma.- 6.12.2.2 Addendum: Primary Lymphoma of the Vagina.- 6.12.2.3 Secondary Uterine and Vaginal Lymphoma.- 6.12.3 Malignant Lymphoma of the Ovary.- 6.12.3.1 Primary Lymphoma of the Ovary.- 6.12.3.2 Secondary Lymphoma of the Ovary.- 6.12.4 Lymphoma of Testis.- 6.12.5 Malignant Lymphoma of the Prostate.- 6.12.6 Lymphoma of the Kidney.- 6.12.6.1 Primary Lymphoma of the Kidney.- 6.12.6.2 Secondary Kidney Lymphoma.- 6.12.7 Malignant Lymphoma of the Urinary Bladder.- 6.13 Endocrine Gland Lymphoma.- 6.13.1 Malignant Lymphoma of the Thyroid Gland.- 6.13.2 Malignant Lymphoma of the Adrenal Gland.- 6.14 Cutaneous Lymphoma.- 6.14.1 Primary Cutaneous B-Cell Lymphoma.- 6.14.1.1 Cutaneous Marginal Zone B-Cell Lymphoma/SALT.- 6.14.1.2 Follicular Lymphoma.- 6.14.1.3 Plasmacytoma.- 6.14.1.4 Diffuse Large-B-Cell Lymphoma.- 6.14.2 Cutaneous T-Cell Lymphoma.- 6.14.2.1 Mycosis Fungoides — Classical Type.- 6.14.2.2 Sézary’s Syndrome.- 6.14.2.3 Primary Cutaneous CD30+ T-Cell Lymphoproliferative Disorders.- 6.14.2.4 Primary Cutaneous NK/T-Cell Lymphoma.- 6.15 Lymphoma of Soft Tissues.- 6.16 Lymphoma of the Bone.- 6.16.1 Primary Lymphoma of Bone.- 6.16.2 Secondary Bone Lymphoma.- 6.17 Lymphoma of the Central Nervous System.- 6.18 Intravascular Large-B-Cell Malignant Lymphoma.- References.- 7 Plasma Cell Proliferations.- 7.1 Plasma Cell Myeloma/Bone Marrow Plasmacytoma.- 7.1.1 Clinical Variants.- 7.1.1.1 Diffuse Decalcifying Myelomatosis.- 7.1.1.1 Osteosclerotic Myeloma.- 7.1.1.1 Nonsecretory Myeloma.- 7.1.1.1 Solitary Myeloma.- 7.1.1.1 Plasma Cell Leukemia.- 7.1.1.1 Variants with Peculiar Clinical Behavior.- 7.2 Extraosseous (Extramedullary) Plasmacytoma.- 7.3 Associated Diseases.- 7.3.1 Castleman’s Disease.- 7.3.2 POEMS Syndrome.- 7.3.3 Primary Amyloidosis.- 7.3.4 Light- and/or Heavy-Chain Deposition Diseases.- 7.4 Heavy-Chain Diseases.- References.- 8 Lymphoma Occurring in a Setting of Immunodeficiency.- 8.1 Lymphoproliferative Disorders Associated with Congenital Immunodeficiencies.- 8.1.1 Ataxia-Telangiectasia.- 8.1.2 Wiskott-Aldrich Syndrome.- 8.1.3 Common Variable Immunodeficiency Disorder.- 8.1.4 Severe Combined Immunodeficiency.- 8.1.5 X-linked Lymphoproliferative Disorder.- 8.1.6 Hyper-IgM Syndrome.- 8.1.7 JOB Syndrome.- 8.1.8 Nijmegen Breakage Syndrome.- 8.2 Lymphoma and Lymphoproliferative Disorders Associated with Acquired Immunodeficiency.- 8.2.1 HIV-Related Lymphoma.- 8.2.2 Post-transplant Lymphoproliferative Disorders.- 8.2.2.1 Plasmacytic Hyperplasia and Infectious-Mononucleosis-like PTLD.- 8.2.2.2 Polymorphic PTLD.- 8.2.2.3 Monomorphic B-Cell PTLD.- 8.2.2.4 Monomorphic T-Cell PTLD.- 8.2.2.5 Hodgkin’s-Like PTLD.- References.- 9 Practical Guidelines for Lymphoma Diagnosis in Bone Marrow.- 9.1 Patterns of Involvement.- 9.1.1 Paratrabecular Infiltrates.- 9.1.2 Intertrabecular Infiltrates.- 9.1.2.1 Interstitial Infiltrate.- 9.1.2.2 Nodular Infiltrate.- 9.1.2.3 Massive Infiltrate.- 9.1.2.4 Monocellular Dispersion.- 9.1.3 Intrasinusoidal Infiltrate.- 9.2 Associated Lesions or Modifications.- 9.2.1 Reticulum Fibers Framework.- 9.2.2 Vascular Modifications.- 9.2.3 Reactive Changes.- Interstitial Edema.- Polyclonal Plasmacytosis.- Reactive Lymphoid Nodules.- Chronic Inflammation.- Eosinophilic Necrosis.- Modifications of the Normal Hematopoietic Cell Lines.- 9.3 Diagnosis of Bone Marrow Involvement According to the Different Types of Lymphoma.- 9.3.1 Small B-Cell Lymphoma (Kroft et al. 1995).- 9.3.1.1 B-Cell Chronic Lymphocytic Leukemia.- 9.3.1.2 B-Prolymphocytic Leukemia.- 9.3.1.3 Lymphoplasmacytic Lymphoma.- 9.3.1.4 Follicular Lymphoma.- 9.3.1.5 Mantle Cell Lymphoma.- 9.3.1.6 Primary Splenic and Nodal and Extranodal Marginal Zone Lymphoma.- 9.3.1.7 Hairy Cell Leukemia.- 9.3.1.8 Myeloma.- 9.3.1.9 Differential Diagnosis.- 9.3.2 Large B-Cell Lymphoma.- 9.3.2.1 T-Cell-Rich/Histiocyte-Rich Large-B-Cell Lymphoma.- 9.3.2.2 Intravascular Large B-Cell Lymphoma.- 9.3.3 Burkitt’s Lymphoma.- 9.3.4 Precursor Cell Lymphoma (B- and T-Cell Lymphoblastic Lymphoma or Acute Leukemia).- 9.3.5 NK/T-Cell Lymphoma.- 9.3.5.1 T-Prolymphocytic Leukemia.- 9.3.5.2 T-Cell Large Granular Lymphocytic Leukemia.- 9.3.5.3 Peripheral T-Cell Leukemia Lymphoma, Unspecified.- 9.3.5.4 Peripheral T-Cell-Lymphoma, Angioimmunoblastic.- 9.3.5.5 Anaplastic Large-Cell Lymphoma.- 9.3.5.6 Hepatosplenic T-Cell Lymphoma.- 9.3.5.7 General Comments.- 9.4 Differential Diagnosis.- 9.4.1 Reactive Lymphoid Nodules.- 9.4.2 Reactive Intravascular Lymphocytosis.- 9.4.3 Hodgkin’s Lymphoma.- 9.4.4 Non-lymphoid Acute Leukemia.- 9.4.5 Systemic Mastocytosis.- 9.4.6 Undifferentiated Carcinoma.- References.- 10 Practical Advice: Methods for the Diagnosis of Malignant Lymphoma.- 10.1 The Diagnosis of Malignant Lymphoma.- 10.1.1 Practical Tips.- 10.2 Immunohistochemistry and Molecular Clonality Analysis in the Diagnosis of Lymphoma.- References.