Diffuse large B-cell lymphoma
Diffuse large B cell lymphoma, abbreviated DLBCL, is a very common lymphoma with a poor prognosis.
General
- Poor prognosis.
- May arise from follicular lymphoma.
- Most common form of non-Hodgkin lymphoma (in the USA).[1]
Microscopic
- Large lymphoid cells:
- 4-5x the diameter of a small lymphocytes.
- Marked cell-to-cell variation in size and shape.
- Cytoplasm usually basophilic and moderate in abundance.
- +/-Prominent nucleoli, may be peripheral and/or multiple.
- Not follicular - nodular arrangement.
- Follicular arrangement = follicular lymphoma.
Notes:
- Large bizarre cells can occasionally mimic Reed-Sternberg cells, seen in Hodgkin lymphoma.
Images:
Special DLBCL subtypes
- Primary mediastinal B-cell lymphoma (PMBL) - esp. in young adults.
- T-cell/histiocyte-rich large B cell lymphoma.
- Primary DLBCL of the CNS.
- EBV-positive DLBCL of the elderly.
- DLBCL associated with chronic inflammation.
- Intravascular LBCL.
- ALK-positive LBCL.
- Plasmablastic lymphoma.
- LBCL arising in HHV-8 associated multicentric Castleman disease.
- Primary effusion lymphoma.
- Lymphomatoid granulomatosis.
Differential diagnosis
- Carcinoma.
- Anaplastic large cell lymphoma (ALCL).
- Follicular lymphoma.
- If a nodular architecture is present it is follicular lymphoma.
- Post-transplant lymphoproliferative disorder (PTLD) - in organ transplant recipients.
- Primary effusion lymphoma - seen in HIV infections.
- Mixed cellularity Hodgkin lymphoma - esp. for T-cell/histiocyte-rich large B cell lymphoma.
IHC
Subclassification
There is a subclassification based on molecular testing:
- Germinal centre (GC) subtype.
- Non-germinal centre (Non-GC) subtype.
The following IHC algorithm has been subsequently developed to reproduce the molecular categorization:[3]
| DLBCL | |||||||||||||||||||||||||
| CD10 -ve | CD10 +ve GC | ||||||||||||||||||||||||
| BCL6 -ve Non-GC | BCL6 +ve | ||||||||||||||||||||||||
| MUM1 -ve GC | MUM1 +ve Non-GC | ||||||||||||||||||||||||
"UHN panel"
- H&E 2 micrometers.
- CD20 -- B cells.
- CD10 -- follicular lymphoma.
- BCL6 -- follicular lymphoma.
- BCL2 -- follicular lymphoma.
- MUM1 -- B cells.
- CD21 -- highlight FDC networks if present.
- CD23 -- highlight FDC networks if present.
- MIB1 -- proliferative rate.
- EBER -- EBV.
- CD3 -- T cells.
- CD5 -- T cells.
- Unstained x4.
Molecular
- Rearrangements of BCL6.[4]
- Can be assessed with an ISH break apart probe.
- Translocation typical of follicular lymphoma: t(14;18)(q32;q21)/IGH-BCL2.[5]
See also
- Haematopathology.
- Lymph nodes.
- Lymph node pathology.
- Lymphoma.
- Small round cell tumours.
- Post-transplant lymphoproliferative disorder (PTLD).
References
- ↑ 1.0 1.1 Mitchell, Richard; Kumar, Vinay; Fausto, Nelson; Abbas, Abul K.; Aster, Jon (2011). Pocket Companion to Robbins & Cotran Pathologic Basis of Disease (8th ed.). Elsevier Saunders. pp. 321. ISBN 978-1416054542.
- ↑ Cotran, Ramzi S.; Kumar, Vinay; Fausto, Nelson; Nelso Fausto; Robbins, Stanley L.; Abbas, Abul K. (2005). Robbins and Cotran pathologic basis of disease (7th ed.). St. Louis, Mo: Elsevier Saunders. pp. 676 (???). ISBN 0-7216-0187-1.
- ↑ Choi, WW.; Weisenburger, DD.; Greiner, TC.; Piris, MA.; Banham, AH.; Delabie, J.; Braziel, RM.; Geng, H. et al. (Sep 2009). "A new immunostain algorithm classifies diffuse large B-cell lymphoma into molecular subtypes with high accuracy.". Clin Cancer Res 15 (17): 5494-502. doi:10.1158/1078-0432.CCR-09-0113. PMID 19706817.
- ↑ Online 'Mendelian Inheritance in Man' (OMIM) 109565
- ↑ Vitolo U, Ferreri AJ, Montoto S (June 2008). "Follicular lymphomas". Crit. Rev. Oncol. Hematol. 66 (3): 248–61. doi:10.1016/j.critrevonc.2008.01.014. PMID 18359244.