Definition and epidemiology
Non-Hodgkin lymphoma (NHL) encompasses a heterogeneous group of malignancies originating from B lymphocytes (about 85-90% of cases), T lymphocytes, or NK cells, at varying stages of maturation. Unlike Hodgkin lymphoma, NHL lacks Reed-Sternberg cells and tends to spread in a less predictable, often non-contiguous pattern.
NHL is far more common than Hodgkin lymphoma, representing roughly 4% of all cancers in the United States. Incidence increases with age, with a median age at diagnosis in the mid-60s. Risk is higher in males and in individuals with immunodeficiency.
Common subtypes
- Diffuse large B-cell lymphoma (DLBCL) - most common subtype overall, aggressive
- Follicular lymphoma - most common indolent subtype
- Mantle cell lymphoma - aggressive, often advanced at diagnosis
- Burkitt lymphoma - highly aggressive, associated with EBV and MYC translocation
- MALT lymphoma - extranodal marginal zone, associated with chronic inflammation (e.g., H. pylori gastritis)
- Peripheral T-cell lymphomas - less common, generally poorer prognosis
- Excisional lymph node biopsy, not FNA, is required for diagnosis because architecture must be assessed.
- DLBCL is the most common NHL subtype overall; follicular lymphoma is the most common indolent subtype.
- t(14;18) BCL2 is characteristic of follicular lymphoma; t(8;14) MYC defines Burkitt lymphoma; t(11;14) cyclin D1 defines mantle cell lymphoma.
- Burkitt lymphoma shows a 'starry sky' pattern on histology and is associated with EBV.
- Gastric MALT lymphoma is linked to H. pylori and can regress with antibiotic eradication alone.
- R-CHOP is first-line therapy for DLBCL.
- LDH level and the International Prognostic Index (IPI) are key prognostic tools.
- Unlike Hodgkin lymphoma, NHL often spreads in a non-contiguous pattern and has more frequent extranodal involvement.
Etiology and risk factors
Most cases arise from acquired genetic alterations with no single identifiable cause, but several associations are well established.
- Immunosuppression: HIV/AIDS, post-transplant immunosuppression (PTLD), congenital immunodeficiency
- Infections: Epstein-Barr virus (Burkitt lymphoma, some DLBCL), Helicobacter pylori (gastric MALT lymphoma), Human T-lymphotropic virus-1 (adult T-cell leukemia/lymphoma), Hepatitis C (splenic marginal zone lymphoma)
- Autoimmune disease: Sjogren syndrome (MALT lymphoma), celiac disease (enteropathy-associated T-cell lymphoma), Hashimoto thyroiditis
- Chromosomal translocations: t(14;18) BCL2 in follicular lymphoma, t(8;14) MYC in Burkitt lymphoma, t(11;14) cyclin D1 in mantle cell lymphoma
- Environmental exposure: pesticides, prior radiation, certain chemotherapy agents
- Family history of lymphoma or other hematologic malignancy
Pathophysiology
NHL results from malignant clonal proliferation of lymphocytes arrested at a specific stage of differentiation, driven by chromosomal translocations and mutations that disrupt normal apoptosis, proliferation, or differentiation control.
In follicular lymphoma, t(14;18) places BCL2 under the immunoglobulin heavy-chain promoter, causing BCL2 overexpression and resistance to apoptosis. In Burkitt lymphoma, t(8;14) dysregulates MYC, driving unchecked proliferation and producing the classic 'starry sky' histologic pattern from interspersed macrophages. In mantle cell lymphoma, t(11;14) causes cyclin D1 overexpression, accelerating cell cycle progression.
Tumor cells accumulate in lymph nodes and can infiltrate extranodal sites (gastrointestinal tract, skin, bone marrow, CNS), reflecting the normal recirculation pattern of lymphocytes. Aggressive subtypes have high proliferative indices and present with rapidly enlarging masses, while indolent subtypes grow slowly and may be asymptomatic for years.
Clinical features
Presentation varies by subtype and site but shares common patterns.
- Painless lymphadenopathy - most common presentation, often cervical, axillary, or inguinal
- B symptoms - fever, night sweats, unintentional weight loss (more common in aggressive subtypes)
- Fatigue and generalized malaise
- Extranodal involvement - GI tract (abdominal pain, bleeding, obstruction), skin lesions, bone marrow infiltration (cytopenias), CNS symptoms in high-grade disease
- Hepatosplenomegaly in advanced disease
- Superior vena cava syndrome or airway compression from mediastinal masses, seen particularly in lymphoblastic lymphoma and some aggressive subtypes
- Rapidly growing mass suggests aggressive histology (e.g., Burkitt, DLBCL); slowly waxing-and-waning nodes suggest indolent disease (e.g., follicular)
Diagnosis
Definitive diagnosis requires tissue, and the biopsy approach is a frequently tested point.
Biopsy
- Excisional lymph node biopsy is the gold standard - preserves architecture needed to distinguish subtypes
- Fine-needle aspiration is insufficient for definitive classification because it does not show nodal architecture
Workup after biopsy confirmation
- Immunohistochemistry/flow cytometry: CD20 (B cells), CD3 (T cells), cyclin D1 (mantle cell), CD10/BCL6 (germinal center), Ki-67 proliferation index
- Cytogenetics/molecular studies: detect characteristic translocations (BCL2, MYC, cyclin D1)
- Staging: CT or PET-CT of chest, abdomen, pelvis; bone marrow biopsy; lumbar puncture if CNS involvement suspected
- Ann Arbor staging system (same as Hodgkin lymphoma) classifies extent of nodal and extranodal involvement
- Laboratory tests: CBC, LDH (prognostic marker reflecting tumor burden), uric acid, comprehensive metabolic panel, HIV and hepatitis B/C serologies (relevant before immunosuppressive therapy)
- International Prognostic Index (IPI): incorporates age, stage, LDH, performance status, and number of extranodal sites to predict outcome
Differential diagnosis
- Hodgkin lymphoma - contiguous spread, Reed-Sternberg cells on biopsy, often younger bimodal age distribution
- Reactive lymphadenopathy - infectious or inflammatory, typically tender, resolves with treatment of underlying cause
- Chronic lymphocytic leukemia/small lymphocytic lymphoma - clonal lymphocytosis, smudge cells on peripheral smear
- Infectious mononucleosis - EBV-driven, atypical lymphocytes, self-limited
- Tuberculosis or other granulomatous lymphadenitis
- Metastatic carcinoma to lymph nodes - epithelial markers on biopsy differentiate from lymphoma
- Sarcoidosis - non-caseating granulomas, bilateral hilar lymphadenopathy on imaging
Management
Treatment depends heavily on histologic subtype, stage, and aggressiveness; management differs markedly between indolent and aggressive lymphomas.
Aggressive lymphomas (e.g., DLBCL)
- R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone) is standard first-line therapy for most patients
- CNS prophylaxis considered in high-risk cases (testicular, sinus, high IPI)
- CAR T-cell therapy is an option for relapsed/refractory disease
Indolent lymphomas (e.g., follicular lymphoma)
- Early, asymptomatic disease may be managed with watchful waiting
- Symptomatic or advanced disease treated with rituximab-based immunochemotherapy regimens
- Localized disease may be treated with radiotherapy alone
Highly aggressive lymphomas (e.g., Burkitt)
- Intensive, short-duration multi-agent chemotherapy regimens with CNS prophylaxis given the high risk of CNS involvement and tumor lysis syndrome
- Tumor lysis syndrome prophylaxis (hydration, allopurinol or rasburicase) is essential given rapid cell turnover
Special situations
- MALT lymphoma associated with H. pylori: eradication therapy alone can induce remission in early, localized gastric disease
- Relapsed/refractory disease: autologous or allogeneic stem cell transplant, CAR T-cell therapy, or targeted agents (e.g., BTK inhibitors, BCL2 inhibitors) depending on subtype
Guideline consensus (NCCN, ESMO) broadly agrees on rituximab-based chemoimmunotherapy as the backbone for B-cell NHL; specific regimen choice and consolidation strategies vary by subtype and are refined in individual guideline updates.
Complications and prognosis
Prognosis varies widely by subtype, stage, and IPI score.
- DLBCL: potentially curable; roughly 60-70% of patients achieve long-term remission with R-CHOP, though outcomes are worse with high IPI scores
- Follicular lymphoma: generally indolent with long survival (often many years), but considered incurable with standard therapy and can transform to a more aggressive histology (e.g., DLBCL)
- Burkitt lymphoma: highly aggressive but highly curable with intensive chemotherapy, especially in children
- Mantle cell lymphoma: historically poorer prognosis, though outcomes have improved with newer regimens
Key complications
- Tumor lysis syndrome - especially with high-grade, rapidly proliferating lymphomas after treatment initiation
- Transformation of indolent to aggressive histology
- Treatment-related toxicity - cardiotoxicity (anthracyclines), infection risk from immunosuppression, secondary malignancies
- CNS relapse in high-risk aggressive subtypes
- Bone marrow failure from marrow infiltration or treatment
BCL2, MYC, cyclin D1 - 'B cells Love Cycling': BCL2 (follicular, t14;18), MYC (Burkitt, t8;14), cyclin D1 (mantle cell, t11;14) - remember by translocation partner chromosome 14 pairing with 18, 8, and 11 respectively.
Practice questions
1. A 68-year-old man presents with a rapidly enlarging, painless neck mass over the past 6 weeks, along with fevers and a 7-kg weight loss. Excisional biopsy shows diffuse large atypical lymphoid cells with high proliferative index, CD20 positive. Which of the following is the most appropriate initial treatment?
2. A 9-year-old boy in a region endemic for malaria presents with a rapidly growing jaw mass. Biopsy reveals a 'starry sky' pattern with sheets of monotonous intermediate-sized lymphoid cells and numerous tingible-body macrophages. Cytogenetic analysis shows a translocation involving chromosomes 8 and 14. Which gene is dysregulated by this translocation?
3. A 55-year-old woman with longstanding Sjogren syndrome presents with persistent dyspepsia unresponsive to proton pump inhibitors. Endoscopic biopsy of the stomach reveals a low-grade B-cell lymphoid infiltrate, and testing confirms Helicobacter pylori infection. Which of the following is the most appropriate first step in management?
Frequently asked questions
What causes non-Hodgkin lymphoma?
Non-Hodgkin lymphoma results from acquired genetic mutations and chromosomal translocations in B, T, or NK lymphocytes, with no single cause identified in most cases. Known risk factors include immunosuppression (HIV, transplant), infections such as EBV, H. pylori, and HTLV-1, autoimmune diseases, and certain chromosomal translocations like t(14;18) in follicular lymphoma. Age over 60 and male sex also increase risk.
What are the first symptoms of non-Hodgkin lymphoma?
The earliest symptom is usually painless, enlarged lymph nodes, most often in the neck, armpit, or groin, that persist or grow over weeks. Some patients also develop B symptoms including fever, night sweats, and unintentional weight loss, along with fatigue. Aggressive subtypes can present more acutely with rapidly enlarging masses, while indolent subtypes may be noticed incidentally.
How is non-Hodgkin lymphoma diagnosed?
Diagnosis requires an excisional lymph node biopsy to examine tissue architecture, since fine-needle aspiration alone cannot reliably classify the subtype. Immunohistochemistry, flow cytometry, and cytogenetic testing identify the specific cell lineage and characteristic genetic abnormalities. Staging with CT or PET-CT imaging, bone marrow biopsy, and blood tests including LDH complete the workup.
Is non-Hodgkin lymphoma curable?
Curability depends heavily on the subtype. Aggressive lymphomas like diffuse large B-cell lymphoma and Burkitt lymphoma are often curable with intensive chemoimmunotherapy, achieving long-term remission in a majority of patients. Indolent subtypes such as follicular lymphoma typically have long survival but are usually not curable with standard treatment and may require ongoing management over years.
Non-Hodgkin lymphoma vs Hodgkin lymphoma — what is the difference?
Hodgkin lymphoma is defined by the presence of Reed-Sternberg cells and classically spreads in a predictable, contiguous pattern through lymph node chains, with a bimodal age distribution. Non-Hodgkin lymphoma lacks Reed-Sternberg cells, is more heterogeneous in cell origin and behavior, spreads less predictably, more often involves extranodal sites, and is generally more common overall, particularly in older adults.
Key drugs
Related conditions and differentials
Sources and further reading
StatPearls (NCBI Bookshelf)MedlinePlusWHO ICD-10: C85.9
Educational content for medical students, prepared by the WhiteCoat Pro editorial team with AI assistance; every page is reviewed by a second AI model for factual errors. It is not medical advice and does not replace the product label, local guidelines or a clinician.