Lymphoma Types Quiz

Lymphoproliferative Disorders

• Mantle Cell Lymphoma: characterized by medium-sized lymphoid cells with irregular nuclear outlines, replacement of normal nodal architecture with a diffuse proliferation of monotonous, medium-sized lymphoid cells.
• Follicular Lymphoma: originates from germinal center B cells, recapitulates follicular architecture, and is characterized by numerous closely spaced follicles replacing normal nodal architecture.
• Burkitt Lymphoma: characterized by medium-sized, highly proliferating lymphoid cells with basophilic vacuolated cytoplasm, a diffuse lymphoid proliferation with a "starry sky" pattern, and three variants (endemic, sporadic, and immunodeficiency-associated).

Cutaneous Lymphoma

• Mycosis Fungoides & Sézary Syndrome: affects T lymphocytes, characterized by small to medium-sized lymphoid cells with irregular nuclear outlines (cerebriform nuclei), and peripheral blood smear and bone marrow showing predominance of myeloblasts.

Acute Leukemia

• M2: characterized by fatigue, symptoms of bleeding, hepatomegaly, splenomegaly, and lymphadenopathy, with myeloblasts predominant in peripheral blood smears.
• M3 (Acute Promyelocytic Leukemia): characterized by a balanced reciprocal translocation between chromosomes 15 and 17, associated with DIC, and a severe bleeding tendency with a fatal course.
• Duration: classified into acute (days to 6 months), subacute (2 to 6 months), and chronic (1 or 2 years or more) leukemia.

Lymphoma

• General: a malignancy that starts in the lymph system, mainly the lymph nodes, with two main types: Hodgkin lymphoma and non-Hodgkin lymphoma.

Myeloma

• A form of cancer: affecting plasma cells, characterized by overgrowth, forming a mass or tumor in the bone marrow.

Other Lymphoproliferative Disorders

• Hairy Cell Leukemia: characterized by small B lymphocytes with abundant cytoplasm and fine ("hairy") cytoplasmic projections, more common in males than females, with clinical findings of fatigue, anemia, leukocytopenia, thrombocytopenia, splenomegaly, and marrow fibrosis.
• Hodgkin's Lymphoma: a malignant lymphoma distinguished by the presence of Reed-Sternberg cells, divided into classical Hodgkin and nodular lymphocyte-predominant Hodgkin.
• Myeloproliferative Disorders/Neoplasms: characterized by excessive proliferation of one or more mature myeloid cell lines, with the propensity to transform into other MPNs or progress into acute leukemias.

Leukemia

• Recognized as a distinct clinical disorder by Virchow between 1839 and 1845
• Named "leukemia" due to the white appearance of blood from patients with fever, weakness, and lymphadenopathy
• Abnormal, uncontrolled proliferation and accumulation of one or more hematopoietic cells

Symptoms of Leukemia

• Fatigue and weakness
• Increased infections
• Bleeding and bruising
• Anemia
• Swollen lymph nodes
• Enlarged spleen or liver
• Bone pain or tenderness

Leukemia vs Lymphoma vs Myeloma

• Leukemia: a disease of the blood and bone marrow, characterized by overproduction of immature or mature leukocytes
• Lymphoma: a malignancy that starts in the lymph system, mainly the lymph nodes
• Myeloma: a form of cancer of the plasma cells, characterized by the overgrowth of cells, forming a mass or tumor in the bone marrow

Classification of Leukemia

• Duration: acute (days to 6 months), subacute (2 to 6 months), and chronic (1 or 2 years or more)
• Number of white blood cells present in peripheral blood (PBS)
• World Health Organization (WHO) classification: acute leukemia (>20% peripheral blood and bone marrow blasts)

Subclassification of Leukemia

• Cellular morphology
• Cytochemical stains (cytochemistry)
• Immunophenotyping (flow cytometry)
• Cytogenetic abnormalities
• Clinical syndrome

Cytogenetic Analysis

• Laboratory study of visible chromosome abnormalities (e.g., deletions, translocations, aneuploidy)
• Identifies abnormalities in the number or structure of chromosomes

Cytochemistry

• Uses specialized stains to detect cellular enzymes and other chemicals in peripheral blood films and bone marrow aspirate smears
• Used to differentiate hematologic diseases, especially leukemias

Immunophenotyping (Flow Cytometry)

• Identifies cells based on the types of markers or antigens present on the cell's surface, nucleus, or cytoplasm
• Uses antibodies to detect markers or antigens on the cells

Acute Lymphoblastic Leukemia (FAB Classification)

• ALL L1: small and homogenous lymphoblasts, scanty cytoplasm, and inconspicuous nucleoli
• ALL L2: large and heterogenous lymphoblasts, abundant cytoplasm, and nucleoli present
• ALL L3: Burkitt-type, large and homogenous lymphoblasts, vacuolated

Acute Myeloid Leukemia (FAB Classification)

• MO: acute myeloid leukemia, minimally differentiated
• M1: acute myeloid leukemia without maturation
• M2: acute myeloid leukemia with maturation
• M3: acute promyelocytic leukemia
• M4: acute myelomonocytic leukemia
• M5B: acute monoblastic leukemia with maturation

Lymphoproliferative Disorders

• Hairy cell leukemia: characterized by small B lymphocytes with abundant cytoplasm and fine (“hairy”) cytoplasmic projections.
• More common in males than in females.
• Bone marrow produces too many abnormal B-lymphocytes.
• Cytochemical feature: strong acid phosphatase reaction that is not inhibited by tartaric acid or tartrate-resistant acid phosphatase (TRAP) stain.

Mantle Cell Lymphoma

• Affects B-cells within the lymph nodes, particularly the "mantle zone".
• Subtype of non-Hodgkin lymphoma (NHL).
• Considered fast-growing compared to other lymphomas.
• Originates from B-cells in the lymph nodes.
• Characterized by medium-sized lymphoid cells with irregular nuclear outlines.
• Derived from the follicular mantle zone.

Follicular Lymphoma

• Originates from germinal center B cells and recapitulates follicular architecture.
• Numerous closely spaced follicles replace the normal nodal architecture.

Burkitt Lymphoma

• Characterized by medium-sized, highly proliferating lymphoid cells with basophilic vacuolated cytoplasm.
• Lymphoid proliferation is diffuse and shows a prominent “starry sky” pattern at low magnification.
• Three variants: endemic (occurring predominantly in Africa), sporadic, and immunodeficiency-associated.

Mycosis Fungoides & Sezary Syndrome

• Mycosis fungoides is the most common cutaneous lymphoma.
• Affects T lymphocytes.
• Sezary cells: small to medium-sized lymphoid cells with irregular nuclear outlines (cerebriform nuclei).

Myeloproliferative Disorders / Neoplasms

• Characterized by excessive proliferation of one or more mature myeloid cell lines (granulocytes, erythrocytes, megakaryocytes, or mast cells)
• Clonal hematopoietic stem cell disorders
• Involve abnormal Janus kinase 2 (JAK2) protein, leading to uncontrolled blood cell growth and division

JAK2 Gene and Mutation

• Provides instructions for making Janus kinase 2 protein, involved in cellular signaling pathway regulating blood cell growth and division in the bone marrow
• JAK2V617F mutation leads to abnormal JAK2 protein, promoting uncontrolled growth and division of blood cells

Types of Myeloproliferative Neoplasms

• Essential Thrombocythemia (ET)
• Polycythemia Vera (PV)
• Idiopathic Myelofibrosis (IMF)
• Chronic Myelogenous Leukemia (CML)
• Chronic Neutrophilic Leukemia (CNL)
• Varies Nucleated Erythrocytes/Megakaryocytes in Myeloproliferation (VNEL)

Chronic Myelogenous Leukemia (CML)

• Affecting granulocytic, monocytic, erythrocytic, and megakaryocytic cell lines
• 90% of cases involve Philadelphia chromosome (chromosome 22 translocated to chromosome 9)
• Associated with BCR/ABL1 abnormality
• Poorer prognosis for patients without Philadelphia chromosome

Myelofibrosis with Myeloid Metaplasia

• Primary Myelofibrosis (PMF)
• Agnogenic Myelofibrosis
• Characterized by fibrosis and granulocytic hyperplasia of the bone marrow
• Granulocytic and megakaryocytic proliferation in the liver and spleen
• Associated with splenomegaly, ineffective hematopoiesis, and JAK2 V617F mutation (65% of PMF patients)

Essential Thrombocythemia (ET)

• Chronic MPD characterized by thrombocytosis (> 1000 x 10^9/L)
• Functionally abnormal platelets, leading to hemorrhage, platelet dysfunction, and thrombosis
• JAK2 V617F mutation found in 50-60% of ET patients
• Supports diagnosis of ET

Polycythemia Vera (PV)

• Characterized by absolute increase in RBC, WBC, and platelets
• JAK2 V617F mutation found in 90-97% of PV patients
• Primary absolute polycythemia, also known as polycythemia Rubra vera
• Patients exhibit ruddy skin coloration due to increased RBC concentration and blood viscosity

Pathophysiological Classification of Polycythemia

• Relative Polycythemia: normal RBC mass, increased hematocrit, normal EPO, decreased plasma volume (dehydration, diarrhea, burns, shock)
• Absolute Polycythemia:
  • Primary Absolute Polycythemia: Polycythemia Vera
  • Secondary Polycythemia with appropriately increased EPO: hypoxia, high altitudes, pulmonary disease, cyanotic heart disease, carboxyhemoglobinemia, high oxygen hemoglobinopathy, 2-3DPG deficiency
  • Secondary Polycythemia with inappropriately increased EPO: neoplasms, acute hepatitis, hepatoma, renal carcinoma, post-renal transplant, Wilms' tumor
  • Genetic Polycythemia/Congenital Secondary Polycythemia: primary familial congenital polycythemia, Chuvash polycythemia

Myelodysplastic Syndromes (MDS)

• Group of disorders resulting from clonal abnormalities of hematopoietic pluripotential stem cells
• Characterized by a hypercellular bone marrow and abnormalities in the cellular maturation of erythroid cells, granulocytes, and megakaryocytes
• Acquired clonal hematologic disorders characterized by progressive cytopenias in the peripheral blood, reflecting defects in erythroid, myeloid, and/or megakaryocytic maturation

Historical Context

• Historically referred to as refractory anemia, smoldering leukemia, oligoblastic leukemia, or preleukemia

Demographics

• Median age at diagnosis: 70

Traditional FAB Cooperative Group Classification of MDS

• Refractory anemia (RA): no specific characteristics mentioned
• Note: The classification table provided is incomplete, and further information is needed to fully understand the classification of MDS.