Difference between revisions of "Follicular lymphoma"
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'''Follicular lymphoma''', abbreviated '''FL''', is a very common non-Hodgkin lymphoma. It is a [[small cell lymphoma]] and usually has an indolent behaviour. | |||
==General== | |||
*A very common type of lymphoma. | |||
*Expresses BCL2,<ref name=pmid18359244>{{cite journal |author=Vitolo U, Ferreri AJ, Montoto S |title=Follicular lymphomas |journal=Crit. Rev. Oncol. Hematol. |volume=66 |issue=3 |pages=248–61 |year=2008 |month=June |pmid=18359244 |doi=10.1016/j.critrevonc.2008.01.014 |url=}}</ref> like many other small cell lymphomas. | |||
==Microscopic== | |||
Features (lymph node): | |||
*Abundant abnormally-shaped lymphoid follicles - '''key feature''' - including some of the following: | |||
**Non-polarized mantle zone (normal mantle zone is usu. thicker at capsular aspect). | |||
**Non-polarized germinal center (normal germinal center has dark & light area). | |||
**Loss of tingible body macrophages. | |||
**Sinuses effaced (lost). | |||
Note: | |||
*The intrafollicular component of the lymph node is compressed - follicles are often described as "kissing", as they nearly touch. | |||
*In [[bone marrow]] specimens the neoplastic cells classically have a paratrabecular arrangement,<ref name=pmid17284114>{{Cite journal | last1 = Iancu | first1 = D. | last2 = Hao | first2 = S. | last3 = Lin | first3 = P. | last4 = Anderson | first4 = SK. | last5 = Jorgensen | first5 = JL. | last6 = McLaughlin | first6 = P. | last7 = Medeiros | first7 = LJ. | title = Follicular lymphoma in staging bone marrow specimens: correlation of histologic findings with the results of flow cytometry immunophenotypic analysis. | journal = Arch Pathol Lab Med | volume = 131 | issue = 2 | pages = 282-7 | month = Feb | year = 2007 | doi = 10.1043/1543-2165(2007)131[282:FLISBM]2.0.CO;2 | PMID = 17284114 }}</ref> i.e. the lymphoma cells are found adjacent to the bone spicules. | |||
DDx: | |||
*Reactive follicular hyperplasia. | |||
*[[Diffuse large B-cell lymphoma]] - esp. for the grade 3B. | |||
===Images=== | |||
*[http://www.flickr.com/photos/euthman/3311641845/ Follicular lymphoma - bone marrow (flickr.com)]. | |||
*[http://library.med.utah.edu/WebPath/HEMEHTML/HEME034.html Follicular lymphoma (utah.edu)]. | |||
===Grading=== | |||
*Grade 1-2: <= 22 centroblasts / HPF; where 1 HPF ~= 0.2376 mm^2 (22 mm eye piece @ 40X objective). | |||
*Grade 3A: >22 centroblasts / HPF; where 1 HPF ~= 0.2376 mm^2 (22 mm eye piece @ 40X objective). | |||
*Grade 3B: only centroblasts (within a nodular architecture). | |||
Notes: | |||
*Significant interobserver variability.<ref>DG. 17 August 2010.</ref> | |||
*Grade 1 & Grade 2 lumped together. | |||
*One should evaluate 10 HPFs. | |||
*''Only'' centroblasts ''without'' a nodular architecture is ''[[Diffuse large B cell lymphoma]]'' ([[DLBCL]]). | |||
The usual cut points mentioned by people with [[HPFitis]] are:<ref name=Ref_Sternberg4_813>{{Ref Sternberg4|813}}</ref> | |||
*Grade 1: 0-5 centroblasts / HPF. | |||
*Grade 2: 5-15 centroblasts / HPF. | |||
*Grade 3: >15 centroblasts / HPF. | |||
==IHC== | |||
Features:<ref name=pmid18359244/> | |||
*CD10 +ve. | |||
*BCL6 +ve. | |||
Others: | |||
*CD5 -ve. | |||
**+ve in mantle cell lymphoma. | |||
*CD23 -ve/+ve. | |||
**+ve in CLL. | |||
*CD43 -ve. | |||
**+ve in mantle cell lymphoma, marginal zone lymphoma. | |||
*CD11c -ve -- flow cytometry only. | |||
*CD21 -ve in tumour cells; highlights follicular dendritic cells. | |||
Image: | |||
*[http://www.pathpedia.com/education/eatlas/histopathology/lymph_node/follicular_lymphoma/follicular-lymphoma-%5B16-ln021_cd21%5D.jpeg Follicular lymphoma - CD21 (pathpedia.com)]. | |||
A panel to work-up: | |||
*BCL2, BCL6, CD3, CD5, CD10, CD20, CD23, cyclin D1. | |||
==Molecular== | |||
*t(14;18)(q32;q21)/IGH-BCL2 in 70-95% of cases.<ref name=pmid18359244/> | |||
**Should not be confused with t(14;18)(q32;q21)/IGH-MALT1 seen in MALT lymphomas.<ref name=pmid16950858>{{cite journal |author=Bacon CM, Du MQ, Dogan A |title=Mucosa-associated lymphoid tissue (MALT) lymphoma: a practical guide for pathologists |journal=J. Clin. Pathol. |volume=60 |issue=4 |pages=361–72 |year=2007 |month=April |pmid=16950858 |pmc=2001121 |doi=10.1136/jcp.2005.031146 |url=}}</ref> | |||
==Sign out== | |||
<pre> | |||
RETROPERITONEAL MASS, RIGHT, CORE BIOPSIES: | |||
- NON-HODGKIN B-CELL LYMPHOMA, FAVOUR FOLLICULAR LYMPHOMA. | |||
COMMENT: | |||
Morphology: | |||
-Small cells: size ~ mature lymphocytes, quantity - many, angular and round. | |||
-Large cells (intermixed with small cells): size ~1.5-2x mature lymphocyte, | |||
small nucleoli, moderate quantity of grey/basophilic cytoplasm, moderate | |||
nuclear pleomorphism. | |||
-Architecture: no gland formation, discohesive, no follicles apparent, no sheets | |||
of large cells. | |||
-Mitoses are uncommon. | |||
Immunohistochemical stains (tumour cells): | |||
Positive: CD45 (strong, membranous/cytoplasmic), CD20 (strong, membranous/cytoplasmic), | |||
BCL-2 (strong, membranous/cytoplasmic), CD10 (strong, membranous), BCL-6 (moderate, | |||
patchy, nuclear). | |||
Negative: pankeratin, CD3, CD5, CD30, CD21 (follicular dendritic cells not apparent), | |||
CD23 (scattered, rare). | |||
Ki-67: highlights the large cells, primarily -- 5-35% of cells within the core. | |||
The findings favour a follicular lymphoma, based on the cellular morphology and | |||
immunostains; however, they are limited by the type of tissue sampling (core biopsy). | |||
Clinical correlation is suggested. | |||
</pre> | |||
==See also== | |||
*[[Small cell lymphomas]]. | |||
*[[Lymphoma]]. | |||
*[[Lymph node pathology]]. | |||
==References== | |||
{{Reflist|2}} | |||
[[Category:Diagnosis]] | [[Category:Diagnosis]] | ||
[[Category:Small cell lymphomas]] |
Revision as of 22:46, 29 December 2013
Follicular lymphoma, abbreviated FL, is a very common non-Hodgkin lymphoma. It is a small cell lymphoma and usually has an indolent behaviour.
General
- A very common type of lymphoma.
- Expresses BCL2,[1] like many other small cell lymphomas.
Microscopic
Features (lymph node):
- Abundant abnormally-shaped lymphoid follicles - key feature - including some of the following:
- Non-polarized mantle zone (normal mantle zone is usu. thicker at capsular aspect).
- Non-polarized germinal center (normal germinal center has dark & light area).
- Loss of tingible body macrophages.
- Sinuses effaced (lost).
Note:
- The intrafollicular component of the lymph node is compressed - follicles are often described as "kissing", as they nearly touch.
- In bone marrow specimens the neoplastic cells classically have a paratrabecular arrangement,[2] i.e. the lymphoma cells are found adjacent to the bone spicules.
DDx:
- Reactive follicular hyperplasia.
- Diffuse large B-cell lymphoma - esp. for the grade 3B.
Images
Grading
- Grade 1-2: <= 22 centroblasts / HPF; where 1 HPF ~= 0.2376 mm^2 (22 mm eye piece @ 40X objective).
- Grade 3A: >22 centroblasts / HPF; where 1 HPF ~= 0.2376 mm^2 (22 mm eye piece @ 40X objective).
- Grade 3B: only centroblasts (within a nodular architecture).
Notes:
- Significant interobserver variability.[3]
- Grade 1 & Grade 2 lumped together.
- One should evaluate 10 HPFs.
- Only centroblasts without a nodular architecture is Diffuse large B cell lymphoma (DLBCL).
The usual cut points mentioned by people with HPFitis are:[4]
- Grade 1: 0-5 centroblasts / HPF.
- Grade 2: 5-15 centroblasts / HPF.
- Grade 3: >15 centroblasts / HPF.
IHC
Features:[1]
- CD10 +ve.
- BCL6 +ve.
Others:
- CD5 -ve.
- +ve in mantle cell lymphoma.
- CD23 -ve/+ve.
- +ve in CLL.
- CD43 -ve.
- +ve in mantle cell lymphoma, marginal zone lymphoma.
- CD11c -ve -- flow cytometry only.
- CD21 -ve in tumour cells; highlights follicular dendritic cells.
Image:
A panel to work-up:
- BCL2, BCL6, CD3, CD5, CD10, CD20, CD23, cyclin D1.
Molecular
- t(14;18)(q32;q21)/IGH-BCL2 in 70-95% of cases.[1]
- Should not be confused with t(14;18)(q32;q21)/IGH-MALT1 seen in MALT lymphomas.[5]
Sign out
RETROPERITONEAL MASS, RIGHT, CORE BIOPSIES: - NON-HODGKIN B-CELL LYMPHOMA, FAVOUR FOLLICULAR LYMPHOMA. COMMENT: Morphology: -Small cells: size ~ mature lymphocytes, quantity - many, angular and round. -Large cells (intermixed with small cells): size ~1.5-2x mature lymphocyte, small nucleoli, moderate quantity of grey/basophilic cytoplasm, moderate nuclear pleomorphism. -Architecture: no gland formation, discohesive, no follicles apparent, no sheets of large cells. -Mitoses are uncommon. Immunohistochemical stains (tumour cells): Positive: CD45 (strong, membranous/cytoplasmic), CD20 (strong, membranous/cytoplasmic), BCL-2 (strong, membranous/cytoplasmic), CD10 (strong, membranous), BCL-6 (moderate, patchy, nuclear). Negative: pankeratin, CD3, CD5, CD30, CD21 (follicular dendritic cells not apparent), CD23 (scattered, rare). Ki-67: highlights the large cells, primarily -- 5-35% of cells within the core. The findings favour a follicular lymphoma, based on the cellular morphology and immunostains; however, they are limited by the type of tissue sampling (core biopsy). Clinical correlation is suggested.
See also
References
- ↑ 1.0 1.1 1.2 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.
- ↑ Iancu, D.; Hao, S.; Lin, P.; Anderson, SK.; Jorgensen, JL.; McLaughlin, P.; Medeiros, LJ. (Feb 2007). "Follicular lymphoma in staging bone marrow specimens: correlation of histologic findings with the results of flow cytometry immunophenotypic analysis.". Arch Pathol Lab Med 131 (2): 282-7. doi:10.1043/1543-2165(2007)131[282:FLISBM]2.0.CO;2. PMID 17284114.
- ↑ DG. 17 August 2010.
- ↑ Mills, Stacey E; Carter, Darryl; Greenson, Joel K; Oberman, Harold A; Reuter, Victor E (2004). Sternberg's Diagnostic Surgical Pathology (4th ed.). Lippincott Williams & Wilkins. pp. 813. ISBN 978-0781740517.
- ↑ Bacon CM, Du MQ, Dogan A (April 2007). "Mucosa-associated lymphoid tissue (MALT) lymphoma: a practical guide for pathologists". J. Clin. Pathol. 60 (4): 361–72. doi:10.1136/jcp.2005.031146. PMC 2001121. PMID 16950858. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2001121/.