Lymphoma

Hodgkin Lymphoma (HL) is characterized by the presence of Reed-Sternberg (RS) cells and typically follows an orderly spread through lymph node chains. It has a bimodal age distribution (peaks at 20-30 and 70-80). Non-Hodgkin Lymphoma (NHL) is a more heterogeneous group (85% B-cell, 15% T-cell) and includes indolent types like Follicular Lymphoma and aggressive types like Diffuse Large B-Cell Lymphoma (DLBCL) or Burkitt Lymphoma. Staging for both is conducted using the Ann Arbor system. Presentation often includes painless, rubbery lymphadenopathy, fever, night sweats, and weight loss (B-symptoms). In HL, pain in lymph nodes after drinking alcohol is a rare but classic symptom. Diagnosis requires an excision node biopsy; fine-needle aspiration (FNA) is usually insufficient for architecture assessment.

Lymphomas result from genetic mutations in lymphocytes at various stages of maturation. HL involves a small number of malignant B-cells (Reed-Sternberg cells) surrounded by a massive infiltrate of reactive non-malignant inflammatory cells. RS cells are typically CD15 and CD30 positive. NHL involves the clonal expansion of B-cells or T-cells. Risk factors include immunosuppression (HIV, post-transplant), autoimmune diseases (Sjogren's, Hashimoto's), and viral infections (EBV for HL and Burkitt; HTLV-1 for Adult T-cell leukaemia/lymphoma; H. pylori for MALT lymphoma). Burkitt lymphoma involves the c-myc oncogene.

Painless lymphadenopathy is the most common presentation, often cervical. B-symptoms are significant for prognosis and staging. HL: Mediastinal masses are common (can cause SVC obstruction) and pruritus is a frequent symptom. NHL: Variable presentation; aggressive types present with rapidly enlarging nodes; indolent types with years of waxing and waning nodes. Extranodal involvement (skin, GI tract, brain) is more common in NHL. Burkitt lymphoma (endemic form) typically presents with a jaw mass.

Bedside: Full physical exam of all node stations and organomegaly. Bloods: FBC, ESR (prognostic in HL), LDH (marker of cell turnover and prognostic in NHL), Liver function, HIV/HBV/HCV screening. Gold Standard: Lymph node excision biopsy (Morphology and Immunohistochemistry). Imaging: CT Chest/Abdomen/Pelvis and PET-CT for staging (PET is essential in HL). Bone marrow biopsy: To assess for Stage IV disease.

Hodgkin Lymphoma: ABVD chemotherapy (Adriamycin, Bleomycin, Vinblastine, Dacarbazine) + Radiotherapy for early stage. Risk of long-term radiotherapy complications (breast cancer, lung cancer, hypothyroidism). Non-Hodgkin Lymphoma (Aggressive): R-CHOP (Rituximab, Cyclophosphamide, Hydroxydaunorubicin, Oncovin/Vincristine, Prednisolone). Non-Hodgkin Lymphoma (Indolent): Often 'watch and wait' if asymptomatic; Rituximab + chemotherapy (e.g., Bendamustine) when progressive. Supportive: Flu vaccine, prophylactic acyclovir/co-trimoxazole during chemo.