Non-Hodgkin lymphoma

Non-Hodgkin lymphomas (NHLs) are a heterogeneous group of malignancies of the lymphoid system.

Clinical history and presenting signs/symptoms depend on the type and location of lymphoma, and stage at presentation.

Diagnosis is confirmed by histopathology (e.g., biopsy of lymph node or extranodal sites) and immunophenotyping.

Diffuse large B-cell lymphoma is the most common type of NHL.

Treatment is based on the histologic subtype and stage; symptom severity informs decisions about when to start therapy.

CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) is the most commonly used chemotherapy regimen.

NHLs are a heterogeneous group of malignancies of the lymphoid system.[1]Armitage JO. Treatment of non-Hodgkin's lymphoma. N Engl J Med. 1993 Apr 8;328(14):1023-30. http://www.ncbi.nlm.nih.gov/pubmed/8450856?tool=bestpractice.com This heterogeneity (>30 entities) stems from the functions of the lymphoid arm of the immune system, which employs various types of lymphocytes to defend against infection and disease.

Lymphoid malignancies can originate from B cells, T cells, or natural killer (NK) cells.

Malignant lymphoid cells retain many qualities of their normal counterparts (B cells to produce immunoglobulins, T cells to travel to extranodal sites such as skin and central nervous system).

This topic does not cover the following NHLs:

• Mycosis fungoides/Sézary syndrome (see  Cutaneous T-cell lymphoma)

• Chronic lymphocytic leukemia/small lymphocytic lymphoma (see  Chronic lymphocytic leukemia)

• Hairy cell leukemia (see  Hairy cell leukemia)

• Waldenström macroglobulinemia (see Waldenström macroglobulinemia)