Lymphoma

Types of Lymphoma

• Hodgkin Lymphoma (HL): A rare form of lymphoma marked by the presence of Reed–Sternberg cells, which are large, abnormal cells derived from B lymphocytes. Hodgkin lymphoma often affects younger people, though it can occur at any age. It typically spreads from one lymph node to the next in an orderly pattern, which can make staging more predictable.
• Non-Hodgkin Lymphoma (NHL): A group of more than 60 different subtypes of lymphoma affecting lymphoid tissues. NHL is much more common than Hodgkin lymphoma and may arise from B cells or T cells. It can spread unpredictably and involve organs such as the liver, spleen, bone marrow, and others.
  
  NHL is further classified into:
  • Indolent (slow-growing) lymphomas
  • Aggressive (fast-growing) lymphomas
  Some indolent types may not require immediate treatment, while aggressive forms require prompt intensive therapy.

Symptoms of Lymphoma

• Painless swollen lymph nodes (neck, underarms, groin)
• Unexplained weight loss
• Fever without obvious infection
• Night sweats (often drenching)
• Persistent fatigue
• Itchy skin (pruritus)
• Abdominal pain or fullness from enlarged spleen or lymph nodes
• Chest pain or difficulty breathing if the chest is affected

Causes and Risk Factors

• Age: Some lymphomas occur more often in older adults, others in younger people
• Weakened immune system: HIV/AIDS, immunosuppressive drugs, or organ transplant
• Autoimmune diseases: e.g., rheumatoid arthritis or lupus
• Family history: Increased risk with close relatives affected
• Infections: Epstein–Barr virus (EBV), Hepatitis C, Helicobacter pylori
• Chemical or radiation exposure: Pesticides, solvents, radiation

Diagnosis of Lymphoma

• Physical examination: Evaluation of lymph nodes, spleen, liver, and symptoms
• Blood tests: May show anaemia, low platelets, or abnormal markers
• Imaging: CT scans and PET scans to assess lymph node and organ involvement
• Lymph node biopsy: Essential for diagnosis; tissue examined for cancer cells
• Bone marrow or spleen biopsy: In selected cases to check disease spread
• Genetic and molecular testing: Helps classify lymphoma subtype and guide treatment

Staging of Lymphoma (Ann Arbor System)

• Stage I: Single lymph node or group of nodes
• Stage II: Two or more node groups on the same side of the diaphragm
• Stage III: Lymph nodes on both sides of the diaphragm
• Stage IV: Spread to organs outside the lymphatic system

Additional “B symptoms” (fever, night sweats, weight loss) help refine staging and prognosis.

Treatment of Lymphoma

• Chemotherapy: First-line treatment for many lymphomas (e.g., ABVD for Hodgkin lymphoma; R-CHOP for many non-Hodgkin lymphomas)
• Radiation therapy: Used for localised disease or combined with chemotherapy
• Immunotherapy: Monoclonal antibodies such as rituximab targeting CD20 on B cells
• Targeted therapies: Drugs targeting specific pathways (e.g., BTK inhibitors, B-cell receptor signalling)
• Stem cell transplant: Considered in relapsed or refractory lymphoma
• CAR T-cell therapy: Advanced immunotherapy for aggressive, relapsed lymphomas

Prognosis

• Hodgkin lymphoma: Excellent prognosis; cure rates >80% in early stages
• Non-Hodgkin lymphoma: Prognosis varies widely by subtype
  • Indolent forms may be controlled for years
  • Aggressive forms can be cured but may relapse
• Better outcomes with early-stage disease and good treatment response