Overview
Definition
A heterogeneous group of malignancies of lymphoid tissues, originating from B-cells (85%), T-cells, or NK-cells, lacking Reed-Sternberg cells.
Epidemiology
Much more common than Hodgkin lymphoma. Incidence increases with age. Associated with immunodeficiency (HIV, post-transplant) and autoimmune diseases (Sjögren's, Hashimoto's).
Etiology & Risk Factors
- Chromosomal translocations (e.g., t(14;18) in Follicular Lymphoma, t(8;14) in Burkitt Lymphoma)
- Infections: H. pylori (MALT lymphoma), EBV, HTLV-1, HCV
Clinical Symptoms
- Painless lymphadenopathy (often disseminated, non-contiguous spread)
- Systemic B symptoms (fever, night sweats, weight loss)
- Extranodal symptoms: GI tract (abdominal pain, early satiety), skin, or CNS involvement
- Fatigue, anemia
Clinical Approach
Diagnosis
- Excisional lymph node biopsy showing follicular or diffuse proliferation of malignant lymphocytes
- Immunophenotyping to identify lineage (B-cell vs T-cell)
- Staging with PET/CT and bone marrow biopsy
Management
- Indolent (e.g., Follicular): Often asymptomatic, manage with observation or Rituximab alone
- Aggressive (e.g., Diffuse Large B-Cell): R-CHOP chemotherapy (Rituximab, Cyclophosphamide, Doxorubicin, Vincristine, Prednisone)
- Highly aggressive (e.g., Burkitt): Intensive chemotherapy + intrathecal prophylaxis
Complications
- Tumor lysis syndrome
- Spinal cord compression / SVC syndrome
- Cytopenias from bone marrow infiltration