The Concept of the Disease
This is a generic terms for a clinical aggressive tumour of B-cells that does not fall into one the definitive disease categories such as Burkitt Lymphoma or Mediastinal B-cell Lymphoma. This is recognised to be a highly heterogeneous group.
How is it Diagnosed?
Lymph Node or other tissue biopsy
- DLBCL consists of a population of highly proliferative large lymphoid cells which invade and destroy the normal structure of the lymph node or other tissues. About a third of cases present in sites other than a lymph node.
- Almost all cases have an abnormal immunophenotype by flow cytometry and immunocytochemistry.
- Monoclonality is demonstrated by antibody or PCR based techniques.
- Translocations involving MYC, BCL2 and BCL6 are commonly demonstrated using FISH. Abnormalities of a wide range of genes, particularly those involving the NFkB pathway are described.
Lymph Node Morphology
Bone Marrow Trephine Morphology
FISH – BCL2 Amplification
What is the Clinical Outcome?
50% of patients treated with R-CHOP chemotherapy are ultimately cured of their disease. However, this masks considerable heterogeneity of outcome.
The International prognostic index (IPI) is the standard method of assessing prognosis at presentation.
|Score||IPI Risk Group|
|0 – 1||Low|
|Risk Factor||Score +0||Score +1|
|Stage (Ann Arbor)||I or II||II or IV|
|Number of extranodal sites||0 or 1||>1|
|Performance Status (ECOG)||0 or 1||>1|
Genetic abnormalities such as translocations involving MYC and the sub-classification of the tumour in germinal centre and activated B-cell types using gene expression profiling are also important determinants of outcome.