Difference between revisions of "Lymphoma"
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==Cutaneous T cell lymphoma== | ==Cutaneous T cell lymphoma== | ||
:See ''[[Dermatologic_neoplasms#Cutaneous_T_cell_lymphoma]]''. | |||
===General=== | ===General=== | ||
*Abbreviated as ''CTCL''. | *Abbreviated as ''CTCL''. |
Revision as of 19:38, 19 August 2010
Lymphoma is almost a specialty for itself. It can be subclassified a number of ways.
This article is an introduction to lymphoma. An introduction to lymph nodes and lymph node pathology that is not lymphoma are in the articles lymph node and lymph node pathology.
Lymphoma classification
Lymphomas can be divided into:
- Hodgkin's lymphoma.
- Non-Hodgkin's lymphoma (NHL).
Other categorizations:
- T cell lymphomas (rare).
- B cell lymphomas (more common).
Two most common NHLs:
- Follicular lymphoma (FL).
- Diffuse large B-cell lymphoma (DLBCL).
Leukemia as a med student
- Acute lymphoid leukemia (ALL) - predominantly in smALL people, i.e. children.
- Acute myeloid leukemia (AML).
- Chronic myeloid leukemia (CML).
- Chronic lymphoid leukemia (CLL) - relatively good prognosis.
Histologic classification
- "Size".
- Nodularity.
"Size"
- The single most important factor for classifying lymphomas.
- Not really based on size.
"Large" | "Small" | Utility | |
Nucleoli | present | absent | most discriminative |
Size | >2x RBC dia. | <2x RBC dia. | moderate |
Chromatin pattern | "open" (pale) | "closed" | moderate/minimal |
Cytoplasm | mold-minimal basophilic cytoplasm |
scant cytoplasm | minimal |
Histologic terms
- Lymphomas = cells look discohesive, may be difficult to differentiate from poor differentiated carcinoma.
- Auer rods = Acute myeloid leukemia.
- Granular cytoplasmic rod (0.5-1 x4-6 micrometres).
- Reed-Sternberg cells = Hodgkin's lymphoma.
- Large cell - very large nucleus.
- Classically binucleated.
- Large cell - very large nucleus.
- Russell bodies = Plasmacytoma (+others).
- Effacement of nodal architecture.
- Loss of proliferation centers.
IHC
General
- CD45.
- AKA common lymphocyte antigen.
- Useful to differentiate from carcinomas (e.g. small cell carcinoma).
T cell markers
- CD2 -- T cell marker (all T cells).
- CD3 -- T cell marker (all T cells).
- CD4 -- subset of T cells.
- CD8 -- subset of T cells.
- CD7 -- often lost first in T cell lymphomas.
- CD5 -- +ve in CLL & mantle cell lymphoma.
- CD43 -- +ve in mantle cell lymphoma
- Alk1.
- TIA1.[2]
- Granzyme B.
B cell markers
- CD20 -- B cell marker.
- CD19 -- B cell marker - used for flow cytometry.
- PAX5 -- nuclear staining.[3]
- Image: PAX5 in Hodgkin's lymphoma.
- CD79a.
- CD10 -- follicle center.
- BCL6 -- follicle center.
- BCL2 -- small B cell lymphomas; T cell marker.
- MUM1.
Follicular dendritic cells
- CD23 -- follicular dendritic cells.
- CD21 -- follicular dendritic cells.
Hodgkin's lymphoma
Classic
- CD30 -- Hodgkin's lymphoma (most sensitive).
- CD15.
Hodgkin's lymphoma
General
- Abbreviated HL.
Microscopic
By definition, HL has Reed-Sternberg cells (RSCs).
Classical HL
Features (classic HL):
- Reed-Sternberg cell.
- Large binucleated cell.
- May be multinucleated.
- May have a horseshoe-like shape.
- Macronucleolus - approximately the size of a RBC (~8 micrometers).
- Well-defined cell border.
- Large binucleated cell.
Notes:
- Large mononuclear cells are common (so called "mononuclear RSCs") but not diagnostic.
Images (classic HL):
- HL mixed cellularity - cytology (WC).
- HL mixed cellularity - cytology (WC).
- HL mixed cellularity (WC).
Subtypes
There are four CHL subtypes:[4]
- Nodular sclerosis CHL - ~70% of CHL.
- Mixed cellular background - T cell, plasma cells, eosinophils, neutrophils and histiocytes.
- Nodular sclerosing fibrosis - thick strands fibrosis.
- Mixed cellularity CHL - ~20-25% of CHL.
- Like nodular sclerosis - but no fibrosis.
- May be associated with HIV infection.[5]
- Lymphocyte-rich CHL - rare.
- T lymphocytes only (no mix of cells).
- Lymphocyte-depleted CHL - rare.
- May be associated with HIV infection.[5]
Memory device:
- The subtypes prevalence is in reverse alphabetical order.
Nodular lymphocyte-predominant HL
Features (nodular lymphocyte-predominant Hodgkin's lymphoma):
- Popcorn cell (previously known as Lymphocytic & histiocytic cell (L&H cell)[6]) - variant of RSC:
- Cells (relatively) small (compared to classic RSCs).
- Lobulated nucleus - key feature.
- Small nucleoli.
- Subtle nodularity at low power (2.5x or 5x objective).
Images (NLPHL):
Follicular lymphoma
Diffuse large B-cell lymphoma
General
- Abbreviated DLBCL.
Microscopic
Features:[7]
- Large cells -- 4-5 times the diameter of a small lymphocytes.
- Typically have marked cell-to-cell variation in size and shape.
- Cytoplasm usu. basophilic and moderate in abundance.
- +/-Prominent nucleoli, may be peripheral and/or multiple.
Notes:
- Large bizarre cells can occasionally mimic Reed-Sternberg cells, seen in Hodgkin lymphoma.
Burkitt's lymphoma
General
- Abbreviated BL.
- Subtyped by etiology.
Microscopic
Features:
- "Starry-sky pattern":
- The stars in the pattern are: tingible-body macrophages.
- Tingible-body macrophages = macrophages containing apoptotic tumour cells.
- The tumour cells are the sky.
- The stars in the pattern are: tingible-body macrophages.
- Tumour cells:[8]
- Medium-sized (~1.5-2x the size of a RBC) with uniform size ("monotonous") -- key feature.
- Round nucleus.
- Small nucleoli.
- Relatively abundant cytoplasm.
- Brisk mitotic rate.
Image: Starry-sky pattern - Ed Uthman (WC).
Plasmacytoma
General
- AKA plasma cell myleoma.
- Malignancy derived from the plasma cells.
- Histologic component of multiple myeloma; to diagnose multiple myeloma other (non-pathology) criteria are needed.
- Prognosis: poor.
Microscopic
Features:
- Abundant eosinophilic cytoplasm.
- Eccentrically placed nucleus.
- Usually with "clock face" morphology.
- "Clock face" morphology = chromatin clumps around the edge of the nucleus, like the numbers on a clock face.
- May have nucleoli.
- Usually with "clock face" morphology.
- Russell bodies:
- Eosinophilic, large (10-15 micrometres), homogenous immunoglobulin-containing inclusions.
- Dutcher bodies - intranuclear crystalline rods.
- Dutcher bodies are PAS stain +ve.[9]
- Image Dutcher bodies (hematologylibrary.org).
- Prominent perinuclear hof - cytoplasmic crescent shaped lucency adjacent to the nuclear membrane (due to large Golgi apparatus); nucleus has a "bib".
Images:
DDx:
- Neuroendocrine carcinoma - nucleus often has a plasmacytoid (plasma cell-like) appearance.
Acute myeloid leukemia
General
- May afflicits young adult.
- Males>females.
Complications
- Chloroma - soft tissue mass.
- Leukostasis.
- Occurs - lungs and brain.[10]
- Hyperviscosity syndrome.
- Spontaneous bleeding with low platelet counts.
Classification
There are two classifications:
- FAB (French-American-British) - based on histologic appearance/maturation.
- WHO classification.
Histology
- Auer rods - not required to diagnose.[11]
- Cytoplasmic granular rods in blast cells.
- Dimensions: approx. 0.5-1 x 4-6 micrometres.
- Images: Auer rods (WP), Auer rods (virginia.edu).
- Cytoplasmic granular rods in blast cells.
Enteropathy-associated T cell lymphoma
General
- Abbreviated EATL.
- AKA enteropathy-type T cell lymphoma (ETTL).
- T cell lymphoma due to celiac disease.
Microscopic
Features:
- Epithelium preserved.
- Small lymphoid cells in the mucosa and submucosa.
Image: EATL (WC).
Angioimmunoblastic T-cell lymphoma
Microscopic
Features:
- Clear cytoplasm.
- "Empty" sinus; subcapsular sinuses "open".
IHC
- CD7 -ve.
- CD20 +ve.
- TIA-1 -ve.
Anaplastic large cell lymphoma
General
- Abbreviated ALCL.
- May look a lot like a carcinoma.
- Often subcapsular in LNs.
- Usually T-cell derived.
- Alk IHC:
- +ve = good prognosis.
- -ve = bad prognosis.
DDx:
- Hodgkin's lymphoma.
Microscopic
Features:
- Large cells with eosinophilic cytoplasm.
- Usu. appear cohesive.
- May be subcapsular.
- Large multinucleated cell - "wreath cell" - key feature.
IHC
Features:
- Variable CD30 +ve. (???)
- CD45 +ve. (???)
Cutaneous T cell lymphoma
General
- Abbreviated as CTCL.
- Sézary syndrome is a subset of CTCL.
Microscopic
Features:[12]
Images:
Table of lymphoma
B cell lymphomas
Name | Size of cells | Site | Histomorphology | IHC | Translocations | Clinical | Prevalence | DDx |
---|---|---|---|---|---|---|---|---|
Follicular lymphoma | small (centrocytes) | lymph node, germinal center | abundant atypical follicles (lack GC polarity, lack polar mantle zone), effaced sinuses, scattered large cells (centroblasts) | CD10+, bcl-6+[15] | t(14,18) | usually indolent, may transform to DLBCL | very common | DLBCL, other small cell lymphomas |
Mantle cell lymphoma | small, monomorphic | lymph node, mantle zone | monomorphic lymphoid, abundant mitoses. +/-scattered epithelioid histiocytes, sclerosed blood vessels | CD5+, CD23-, CD43+, cyclin D1+[15] | t(11;14)(q13;q32)[16] | indolent ??? | uncommon | other small cell lymphomas, PTGC, Castleman disease, Burkitt's lymphoma |
Extranodal marginal zone lymphoma (MALT lymphoma) | small | mucosa-associated lymphoid tissue, GI tract + elsewhere | +/- lymphepithelial lesion (cluster of 3+ cells in epithelium) | CD21+, CD11c+, CD5-, CD23-[15] | ??? | indolent ??? | common | other small cell lymphomas, neuroendocrine tumours |
Precursor B-cell lymphoblastic lymphoma/ leukemia | small | lymph node ??? | ??? | CD10+, CD5-, TdT+, CD99+[15] | translocations ??? | aggressive ??? | uncommon | small cell lymphomas |
Burkitt's lymphoma | medium, monomorphic | lymph node, germinal center (???) | tingible-body macrophages ("starry sky" appearance), round nucleus, small nucleoli, mitoses +++ | CD10+, BCL6+, BCL2- | t(8;14) (q24;q32) | rapid growth, may be associated with EBV, HIV/AIDS | uncommon | DLBCL, mantle cell lymphoma |
Diffuse large B cell lymphoma | large cells (>2x RBC, often larger), variable size | lymph node usually, germinal center | sheets of large discohesive cells; if only nodular = follicular lymphoma | MIB-1 >40% | none / like follicular lymphoma t(14,18) / c-MYC (like Burkitt lymphoma) | poor prognosis | very common | Burkitt lymphoma, ALCL, Hodgkin lymphoma |
T cell lymphomas
Name | Size of cells | Site | Histomorphology | IHC | Translocations | Clinical | Prevalence | DDx |
---|---|---|---|---|---|---|---|---|
Angioimmunoblastic lymphoma | size of cells ? | site ? | histomorphology ? | IHC ? | translocations ? | clinical ? | prevalence ? | DDx ? |
Enteropathy-type T cell lymphoma | size of cells ? | site ? | histomorphology ? | IHC ? | translocations ? | clinical ? | prevalence ? | DDx ? |
Precursor lymphoblastic lymphoma / leukemia | size of cells ? | site ? | histomorphology ? | IHC ? | translocations ? | clinical ? | prevalence ? | DDx ? |
Adult T-cell lymphoma / leukemia | size of cells ? | site ? | histomorphology ? | IHC ? | translocations ? | clinical ? | prevalence ? | DDx ? |
Peripheral T cell lymphoma (NOS) | size of cells ? | site ? | histomorphology ? | TIA-1+ | translocations ? | clinical ? | prevalence ? | DDx ? |
Anaplastic large cell lymphoma | size of cells ? | site ? | histomorphology ? | CD30+/-, Alk+/- | translocations ? | clinical ? | prevalence ? | DDx ? |
Extranodal NK / T cell lymphoma nasal type | size of cells ? | site ? | histomorphology ? | EBER+, CD16+, CD56+, CD57-, TIA-1+, Granzyme B+ | translocations ? | clinical ? | prevalence ? | DDx ? |
Blastic NK cell lymphoma | size of cells ? | site ? | histomorphology ? | IHC ? | translocations ? | clinical ? | prevalence ? | DDx ? |
See also
- Haematopathology - introduction.
References
- ↑ 1.0 1.1 Alanen A, Pira U, Lassila O, Roth J, Franklin RM (March 1985). "Mott cells are plasma cells defective in immunoglobulin secretion". Eur. J. Immunol. 15 (3): 235–42. PMID 3979421.
- ↑ URL: http://www.ncbi.nlm.nih.gov/omim/603518. Accessed on: 18 August 2010.
- ↑ URL: http://www.ncbi.nlm.nih.gov/omim/167414. Accessed on: 18 August 2010.
- ↑ Humphrey, Peter A; Dehner, Louis P; Pfeifer, John D (2008). The Washington Manual of Surgical Pathology (1st ed.). Lippincott Williams & Wilkins. pp. 567. ISBN 978-0781765275.
- ↑ 5.0 5.1 Sissolak G, Sissolak D, Jacobs P (April 2010). "Human immunodeficiency and Hodgkin lymphoma". Transfus. Apher. Sci. 42 (2): 131–9. doi:10.1016/j.transci.2010.01.008. PMID 20138008.
- ↑ Küppers R, Rajewsky K, Braeuninger A, Hansmann ML (March 1998). "L&H cells in lymphocyte-predominant Hodgkin's disease". N. Engl. J. Med. 338 (11): 763–4; author reply 764–5. doi:10.1056/NEJM199803123381113. PMID 9499174.
- ↑ 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.
- ↑ Bellan C, Lazzi S, De Falco G, Nyongo A, Giordano A, Leoncini L (March 2003). "Burkitt's lymphoma: new insights into molecular pathogenesis". J. Clin. Pathol. 56 (3): 188–92. PMC 1769902. PMID 12610094. http://jcp.bmj.com/cgi/pmidlookup?view=long&pmid=12610094.
- ↑ URL: http://www.thefreelibrary.com/Dutcher+bodies+in+chronic+synovitis-a083551789. Accessed on: 4 August 2010.
- ↑ AML. Harrison's 16th Ed.
- ↑ AG. 8 July, 2009.
- ↑ URL: http://emedicine.medscape.com/article/209091-overview. Accessed on: 19 August 2010.
- ↑ URL: http://emedicine.medscape.com/article/204529-diagnosis. Accessed on: 19 August 2010.
- ↑ URL: http://dictionary.reference.com/browse/convoluted. Accessed on: 19 August 2010.
- ↑ 15.0 15.1 15.2 15.3 Lester, Susan Carole (2005). Manual of Surgical Pathology (2nd ed.). Saunders. pp. 95. ISBN 978-0443066450.
- ↑ URL: http://atlasgeneticsoncology.org/Anomalies/t1114ID2021.html. Accessed on: 10 August 2010.