Lymphoma and Multiple Myeloma

Lymph Nodes and Lymphomas

Lymph Node Characteristics

1. Normal Lymph Node Appearance

   • Size and Texture: Should normally be soft, pink, and relatively small.

   • Clinical Condition: An example includes a lymph node from a patient with lymphadenopathy, which appears enlarged.

   • Disease Association: Enlarged nodes may indicate diseases such as Hodgkin's disease or non-Hodgkin's lymphoma.

Hodgkin's Disease

1. Reed-Sternberg Cells

   • Characteristics:

     • Large cells with large, pale nuclei containing large purple nucleoli, often referred to as the "owl's eye."

     • Indicative of Hodgkin's disease.

   • Cellular Composition: Most of the lymph node's cellular content consists of reactive lymphoid cells.

Non-Hodgkin's Lymphomas

1. General Characteristics

   • Demographics: Usually afflicts males over 40 years old.

   • Cell Origin: 70% of cases are of B cell origin.

   • Immunological Impact: Leads to impaired or decreased antibody production.

   • Spread Pattern: Diffuse pattern of cellular spreading within the node, often involving bone marrow.

2. Symptoms

   • Lymphadenopathy: Painless diffuse lymphadenopathy.

   • Mediastinal Involvement: Can lead to lung involvement.

   • Retroperitoneal Involvement: May cause gastrointestinal (GI) involvement.

   • Additional Symptoms: Fever and night sweats.

3. Treatment Options

   • Therapies:

     • Radiation therapy

     • Chemotherapy

     • Immunotherapy

     • CAR-T therapy

Comparison of Hodgkin’s Disease and Non-Hodgkin’s Lymphoma

1. Hodgkin's Disease

   • Localization: More often localized to a single axial group of nodes (cervical, mediastinal, para-aortic).

   • Spread Pattern: Orderly spread by contiguity.

   • Involvment of Specific Nodes: Rarely involves mesenteric nodes and Waldeyer's ring (pharynx).

   • Extranodal Involvement: Uncommon.

2. Non-Hodgkin's Lymphoma

   • Node Involvement: More frequent involvement of multiple peripheral nodes.

   • Spread Pattern: Non-contiguous spread.

   • Involvement of Specific Nodes: Commonly involves Waldeyer's ring and mesenteric nodes.

   • Extranodal Involvement: Common.

Multiple Myeloma

Multiple myeloma is defined as a plasma cell cancer (plasmacytoma) originating in the bone marrow, characterized by involvement of the skeleton at multiple sites.

Pathology of Multiple Myeloma

1. Cell Transformation

   • Origin: Arises from the transformation of a pluripotent stem cell in bone marrow.

   • Differentiation: Predominantly follows the B cell-plasma pathway.

2. Clinical Features

   • Immunoglobulin Production: High levels of non-functional immunoglobulins (specifically IgG and IgA) are produced.

   • Tumor Dependency: Tumor is dependent on the cytokine interleukin-6.

   • Bone Localizations:

     • Localizes to bone, leading to significant bone destruction.

     • X-ray results show a "soap-bubble appearance" of affected bone.

   • Consequences:

     • Hypercalcemia due to bone resorption.

     • Depressed humoral mediated immunity, leading to increased infection risk.

     • Hyperviscosity syndrome due to increased levels of immunoglobulins in the blood.

     • Bence-Jones Proteins: Free immunoglobulin light chains found in plasma that are toxic to renal tubular cells, resulting in renal insufficiency and failure.

   • Radiographic Findings: The skull typically shows characteristic rounded "punched out" lesions, appearing as lucent areas on x-ray.

   • Histological Findings:

     • Abnormal plasma cells occupy the bone marrow cavity.

     • Plasma cells are usually differentiated enough to retain some immunoglobulin production.

     • Myelomas can be identified through an immunoglobulin "spike" on protein electrophoresis of serum or the presence of Bence-Jones proteins in urine.

Treatment of Multiple Myeloma

1. Therapeutic Approaches

   • Intensive chemotherapy followed by bone marrow transplantation.

   • CAR-T therapy is also a noted treatment approach for applicable cases.