Lymphoma Classification

 Many classification systems have been used over the years. Presented here is only the current commonly used REAL/WHO classification system since it is the one currently used by most pathologists. There is a link at the bottom of this page to older systems. The WHO modification of the REAL classification recognizes 3 major categories of lymphoid malignancies based on morphology and cell lineage: B-cell neoplasms, T-cell/natural killer (NK)-cell neoplasms, and Hodgkin's lymphoma. Both lymphomas and lymphoid leukaemias are included in this classification because both solid and circulating phases are present in many lymphoid neoplasms and distinction between them is artificial.

For example, B-cell chronic lymphocytic leukemia and B-cell small lymphocytic lymphoma are simply different manifestations of the same neoplasm, as are lymphoblastic lymphomas and acute lymphocytic leukaemias. Within the B- and T-cell categories, 2 subdivisions are recognized: precursor neoplasms which correspond to the earliest stages of differentiation and more mature differentiated neoplasms.

Click here to read an article about the classification and staging of NHL over the years.

-- Updated REAL/WHO Classification --

NOTE: The WHO has recently adopted a new classification system for cutaneous lymphomas. The classification system below is still the current one used, but it will eventually be integrated with these new changes to the cutaneous lymphomas.

Click here to read about the new cutaneous classification.

B-cell neoplasms    

• I. Precursor B-cell neoplasm: precursor B-acute lymphoblastic leukemia/lymphoblastic lymphoma (B-ALL, LBL)    
• II. Peripheral B-cell neoplasms        
  • A. B-cell chronic lymphocytic leukemia/small lymphocytic lymphoma        
  • B. B-cell prolymphocytic leukemia        
  • C. Lymphoplasmacytic lymphoma/immunocytoma        
  • D. Mantle cell lymphoma        
  • E. Follicular lymphoma        
  • F. Extranodal marginal zone B-cell lymphoma of MALT type        
  • G. Nodal marginal zone B-cell lymphoma (+/- monocytoid B-cells)
  • H. Splenic marginal zone lymphoma (+/- villous lymphocytes)    
  • I. Hairy cell leukemia        
  • J. Plasmacytoma/plasma cell myeloma        
  • K. Diffuse large B-cell lymphoma
  • Primary mediastinal B-cell lymphoma             
  • Primary effusion lymphoma        
  • L. Burkitt's lymphoma

T-cell and putative NK-cell neoplasms    

• I. Precursor T-cell neoplasm: precursor T-acute lymphoblastic leukemia/lymphoblastic lymphoma (T-ALL, LBL)     
• II. Peripheral T-cell and NK-cell neoplasms         
  • A. T-cell chronic lymphocytic leukemia/prolymphocytic leukemia 
  • B. T-cell granular lymphocytic leukemia         
  • C. Mycosis fungoides/Sezary's syndrome         
  • D. Peripheral T-cell lymphoma, not otherwise characterized 
  • E. Hepatosplenic gamma/delta T-cell lymphoma         
  • F. Subcutaneous panniculitis-like T-cell lymphoma         
  • G. Angioimmunoblastic T-cell lymphoma         
  • H. Extranodal T-/NK-cell lymphoma, nasal type         
  • I. Enteropathy-type intestinal T-cell lymphoma         
  • J. Adult T-cell lymphoma/leukemia (HTLV 1+)         
  • K. Anaplastic large cell lymphoma, primary systemic type
  • L. Anaplastic large cell lymphoma, primary cutaneous type
  • M. Aggressive NK-cell leukemia Hodgkin's lymphoma

(Hodgkin's disease)     

• I. Nodular lymphocyte-predominant Hodgkin's lymphoma
• II. Classical Hodgkin's lymphoma
  • A. Nodular sclerosis Hodgkin's lymphoma
  • B. Lymphocyte-rich classical Hodgkin's lymphoma
  • C. Mixed cellularity Hodgkin's lymphoma.
  • D. Lymphocyte depletion Hodgkin's lymphoma

The chart below outlines what types of lymphoma correspond with what stage of B-cell development.  

Indolent / Aggressive classification

The following table classifies all the lymphoproliferative disorders according to whether they belong to the indolent (slow growing) or aggressive subtype. This includes lymphomas, leukaemias, and myelomas.

Indolent lymphoma/leukemia

• A. Follicular lymphoma (follicular small cleaved cell [grade 1], follicular mixed small cleaved and large cell [grade 2], diffuse small cleaved cell)
• B. Chronic lymphocytic leukemia/small lymphocytic lymphoma
• C. Lymphoplasmacytic lymphoma (Waldenstrom's macroglobulinemia)
• D. Extranodal marginal zone B-cell lymphoma (MALT lymphoma
• E. Nodal marginal zone B-cell lymphoma (monocytoid B-cell lymphoma)
• F. Splenic marginal zone lymphoma (splenic lymphoma with villous lymphocytes)
• G. Hairy cell leukemia
• H. Mycosis fungoides/Sezary syndrome
• I. T-cell granular lymphocytic leukemia
• J. Primary cutaneous anaplastic large cell lymphoma/lymphomatoid papulosis (CD30+)
• K. Nodular lymphocyte predominant Hodgkin's lymphoma  

Aggressive lymphoma/leukemia

• A. Diffuse large cell lymphoma (includes diffuse mixed cell, diffuse large cell, immunoblastic, T-cell rich large B-cell lymphoma) Distinguish:
  • 1. Mediastinal large B-cell lymphoma
  • 2. Follicular large cell lymphoma (grade 3)
  • 3. Anaplastic large cell lymphoma (CD30+)
  • 4. Extranodal NK/T-cell lymphoma, nasal type
  • 5. Lymphomatoid granulomatosis (angiocentric pulmonary B-cell lymphoma)
  • 6. Angioimmunoblastic T-cell lymphoma
  • 7. Peripheral T-cell lymphoma, unspecified
  • 8. Subcutaneous panniculitis-like T-cell lymphoma
  • 9. Hepatosplenic T-cell lymphoma
  • 10. Enteropathy-type T-cell lymphoma
  • 11. Intravascular large B-cell lymphoma
• B. Burkitt lymphoma/Burkitt cell leukaemia/Burkitt-like lymphoma
• C. Precursor B- or T-cell lymphoblastic lymphoma/leukaemia
• D. Primary CNS lymphoma
• E. Adult T-cell leukaemia/lymphoma (HTLV 1+)
• F. Mantle cell lymphoma
• G. Polymorphic post-transplantation lymphoproliferative disorder (PTLD)
• H. AIDS-related lymphoma
• I. True histiocytic lymphoma
• J. Primary effusion lymphoma
• K. Aggressive NK-cell leukemia/blastic NK-cell lymphoma
• L. B- or T-cell prolymphocytic leukemia  

Click here to view older classification systems