Non-Hodgkin lymphoma
Non-Hodgkin lymphoma is a heterogeneous group of B-cell (about 85%) and T-cell lymphoid malignancies that spread noncontiguously and often involve extranodal sites, ranging from indolent follicular lymphoma to aggressive diffuse large B-cell lymphoma to highly aggressive Burkitt lymphoma. Diagnosis requires excisional or core biopsy with flow cytometry and cytogenetics, Ann Arbor staging with PET-CT, and treatment is subtype-specific, from observation to R-CHOP to intensive Burkitt regimens with aggressive tumor lysis and CNS prophylaxis.
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What this article covers
- Overview
Definition: non-Hodgkin lymphoma (NHL) is a heterogeneous group of malignancies arising from B lymphocytes (about 85%) or T lymphocytes (about 15%), distinguished from Hodgkin lymphoma by absence of…
- Epidemiology
Peak incidence: ages 65 to 75 years for NHL overall, later than the median age of Hodgkin lymphoma.
- Risk factors
Immunosuppression: HIV infection, transplantation, and inherited immunodeficiencies raise risk, particularly for aggressive and Burkitt-type lymphoma (acute HIV infection).
- Pathophysiology
Malignant clonal proliferation of lymphoid cells arrested at a specific stage of B- or T-cell development, with phenotype and genetics defining the subtype.
- Clinical features
Painless, progressive lymphadenopathy: most common finding, but NHL more often presents with widespread or extranodal disease than the localized cervical onset typical of Hodgkin lymphoma.
- Differential diagnosis
Hodgkin lymphoma: Reed-Sternberg cells on biopsy, bimodal age distribution, contiguous nodal spread with rare extranodal disease (hodgkin lymphoma).
- Diagnosis
Diagnosis is established by excisional or core needle lymph node biopsy showing abnormal architecture, confirmed with flow cytometry and cytogenetic/molecular testing (t(14;18) follicular, t(11;14)…
- Management
Confirm subtype before treating, because management is entirely subtype-driven; do not start chemotherapy before biopsy, flow cytometry, and cytogenetics return, except for a true emergency (airway…
- Complications
Tumor lysis syndrome: hyperuricemia, hyperkalemia, hyperphosphatemia, secondary hypocalcemia, and acute kidney injury, most likely with Burkitt lymphoma, and can occur spontaneously before treatment (tumor lysis syndrome).
- Prognosis
Highly subtype-dependent rather than stage-dependent alone: aggressive and highly aggressive lymphomas have greater cure potential than indolent lymphomas, which are treatable but not curable and relapse over years.
- Prevention
No general primary prevention exists for most NHL subtypes; efforts instead target known drivers of specific subtypes.
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Related articles
- Hodgkin lymphoma
Hodgkin lymphoma is a B-cell malignancy defined by Reed-Sternberg cells that classically presents with painless, contiguously spreading cervical or mediastinal lymphadenopathy in a young adult, and it is confirmed by excisional lymph node biopsy. Ann Arbor/Lugano stage and interim PET response drive risk-adapted ABVD chemotherapy with or without radiation, and most patients are cured.
- Chronic lymphocytic leukemia
Chronic lymphocytic leukemia is the most common adult leukemia, a clonal proliferation of mature B lymphocytes usually discovered as incidental lymphocytosis in older adults with smudge cells on smear. Diagnosis rests on absolute B-lymphocytosis with a characteristic flow cytometry immunophenotype, and asymptomatic early-stage disease is observed while symptomatic or progressive disease is treated with targeted agents such as ibrutinib and venetoclax.
- Cutaneous T-cell lymphoma
Cutaneous T-cell lymphoma is a non-Hodgkin lymphoma of malignant CD4+ T cells that homes to the skin, most often as mycosis fungoides progressing through patch, plaque, and tumor stages, with Sezary syndrome as its aggressive leukemic, erythrodermic variant. Diagnosis rests on skin biopsy showing epidermotropic atypical lymphocytes with Pautrier microabscesses plus clonal T-cell receptor gene rearrangement, and management is staged, from skin-directed therapy in limited disease to systemic agents and extracorporeal photopheresis in advanced or leukemic disease.
- Hairy cell leukemia
Hairy cell leukemia is a rare, indolent mature B-cell neoplasm of older men that produces pancytopenia, massive splenomegaly without lymphadenopathy, and recurrent infection, with circulating hairy cells and a dry marrow tap on aspiration. Diagnosis is confirmed by flow cytometry and treatment with a single course of a purine nucleoside analog, typically cladribine, produces durable remission in most patients.
- Tumor lysis syndrome (TLS)
Tumor lysis syndrome is a metabolic oncologic emergency in which massive tumor cell breakdown, spontaneous or chemotherapy-induced, releases potassium, phosphate, and nucleic acids into the blood, producing hyperuricemia, hyperkalemia, hyperphosphatemia, and secondary hypocalcemia that can precipitate acute kidney injury, arrhythmia, seizure, and death. Risk-stratified prophylaxis with hydration plus allopurinol or rasburicase before chemotherapy, and aggressive correction of electrolytes with renal replacement therapy when needed, are the cornerstones of management.
- Acute HIV infection
Acute HIV infection, also called the acute retroviral syndrome, is the symptomatic viremic phase in the days to weeks after HIV acquisition, presenting with fever, fatigue, myalgia, rash, and pharyngitis at a time when antibody testing may still be negative. Diagnosis requires an HIV RNA viral load, and antiretroviral therapy should begin as soon as the patient is ready, regardless of CD4 count.