Lymphoma and Myeloma Flashcards

Lymphoma and Myeloma

Overview of Hematologic Malignancies

Definition

  • Leukemia: Malignancy of hematopoietic cells that starts in the bone marrow and can spread to blood and lymph nodes. Types include myeloid or lymphoid and can be acute or chronic.

  • Lymphoma: Malignancy specific to lymphoid cells, beginning in lymph nodes and can spread to blood and bone marrow. Types include Hodgkin and non-Hodgkin lymphoma.

Types of Hematologic Malignancies

Leukemias

  • Acute Leukemias: Rapid progression, requires prompt treatment.

  • Chronic Leukemias: Slower progression, might not need immediate intervention.

  • Subcategories include:

    • Myeloid Leukemias

    • Lymphoid Leukemias

Lymphomas

  • Hodgkin Lymphoma: Characterized by the presence of Reed-Sternberg cells.

  • Non-Hodgkin Lymphoma (NHL): More varied types and presentations.

Pathophysiology of Lymphoid and Myeloid Cells

Stem Cells

  • Myeloid Stem Cell Differentiation:

    • Myeloblast → Promyelocyte → Myelocyte → Metamyelocyte → Band → Mature cells (Neutrophil, Eosinophil, Basophil, Monocyte, Platelets, Erythrocyte)

  • Lymphoid Stem Cell Differentiation:

    • Lymphoblast → Mature Lymphocyte

Signs and Symptoms

Lymphadenopathy

  • Definition: Enlarged lymph nodes that may indicate a reaction to infection or malignancy.

  • Common Causes:

    • Benign: Infection.

    • Malignant: Metastatic carcinoma.

Lymph Node Anatomy

Structures of Lymph Nodes

  • Fibrous Capsule: Protective outer covering

  • Afferent Lymphatics: Channels bringing lymph into the node

  • Subcapsular Sinus: Initial area where lymph drains

  • Paracortex: Area for T-cell activation

  • Secondary Follicle: Germinal center for B-cell maturation

  • Medullary Cords & Sinuses: Provide a channel for drained lymph to exit

Non-Hodgkin Lymphoma (NHL)

Presentation and Symptoms

  • Commonly presents as painless, firm lymphadenopathy

  • Possible extranodal manifestations and "B" symptoms:

    • Weight loss

    • Night sweats

    • Fever

Types of Non-Hodgkin Lymphoma (NHL)

Categorization by Grade

  • Low-Grade (Indolent):

    • Small Lymphocytic Lymphoma

    • MALT Lymphoma

    • Follicular Lymphoma

    • Mycosis Fungoides

  • High-Grade (Aggressive):

    • Large Cell Lymphoma

    • Lymphoblastic Lymphoma

    • Burkitt Lymphoma

Clinical Features of Specific Lymphomas

Small Lymphocytic Lymphoma

  • Identical to Chronic Lymphocytic Leukemia (CLL), characterized by the expression of CD5+ B cell marker and BCL2 (inhibits apoptosis).

MALT Lymphoma

  • Associated with Helicobacter pylori; treatable with antibiotics if diagnosed early.

Follicular Lymphoma

  • Characterized by small cleaved cells; average survival dependent on staging. t(14;18) indicates gene rearrangement with bcl-2.

Diffuse Large Cell Lymphoma

  • Most common type of adult lymphoma, rapid growth with poor prognosis.

Hodgkin Lymphoma

Clinical Features

  • Typical in younger patients with localized disease and good prognosis. Risks include secondary malignancies due to treatment.

Reed-Sternberg Cells

  • Characteristic cells used in the diagnosis of Hodgkin lymphoma.

Multiple Myeloma

Definition and Symptoms

  • Malignant proliferation of plasma cells resulting in:

    • Monoclonal gammopathy

    • Commonly secretes IgG.

    • Symptoms:

      • Weakness

      • Infections

      • Renal failure

      • Bone pain; linked to osteolytic lesions.

Treatment of Multiple Myeloma

Interventions

  • Chemo and radiation therapy

  • Bone marrow transplant

  • 5-year survival rate with chemotherapy alone around 20%.