Difference between revisions of "Lymphoma"

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===Microscopic===
===Microscopic===
Features:
Features:<ref></ref>
*Large cells with eosinophilic cytoplasm.
*Large cells with eosinophilic cytoplasm.
*Usually appear cohesive.
*Usually appear cohesive.
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*"Wreath cells" - large (multinucleated) cells with (morphologically) one toroidal-shaped nucleus - '''key feature'''.
*"Wreath cells" - large (multinucleated) cells with (morphologically) one toroidal-shaped nucleus - '''key feature'''.
**C-shaped nuclei may be present suggestive of wreath cells.
**C-shaped nuclei may be present suggestive of wreath cells.
**[[AKA]] "Hallmark cells". (???)
***"Hallmark cells" = horseshoe-shaped or donut-shaped nucleus with an eosinophilic paranuclear region.<ref name=pmid17941004>{{Cite journal  | last1 = Rapkiewicz | first1 = A. | last2 = Wen | first2 = H. | last3 = Sen | first3 = F. | last4 = Das | first4 = K. | title = Cytomorphologic examination of anaplastic large cell lymphoma by fine-needle aspiration cytology. | journal = Cancer | volume = 111 | issue = 6 | pages = 499-507 | month = Dec | year = 2007 | doi = 10.1002/cncr.23120 | PMID = 17941004 | url=http://onlinelibrary.wiley.com/doi/10.1002/cncr.23120/full}}</ref><ref name=pmid12419758>{{Cite journal  | last1 = Ponzoni | first1 = M. | last2 = Terreni | first2 = MR. | last3 = Ciceri | first3 = F. | last4 = Ferreri | first4 = AJ. | last5 = Gerevini | first5 = S. | last6 = Anzalone | first6 = N. | last7 = Valle | first7 = M. | last8 = Pizzolito | first8 = S. | last9 = Arrigoni | first9 = G. | title = Primary brain CD30+ ALK1+ anaplastic large cell lymphoma ('ALKoma'): the first case with a combination of 'not common' variants. | journal = Ann Oncol | volume = 13 | issue = 11 | pages = 1827-32 | month = Nov | year = 2002 | doi =  | PMID = 12419758 }}</ref>)


===IHC===
===IHC===

Revision as of 20:16, 31 May 2011

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.

A general introduction to haematopathology is in the haematopathology article.

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

  1. "Size".
  2. 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.
  • Russell bodies = plasmacytoma (+others).
    • Eosinophilic, large, homogenous immunoglobulin-containing inclusions.[1]
      • Mott cell is a cell that contains Russell bodies.[1]
  • 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).

Others:

  • AE1/AE3 -- to r/o 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[2] - prognostic in anaplastic large cell lymphoma (ALCL).[3]
  • TIA1 - cytotoxic T-cell.[4]
  • Granzyme B.

B cell markers

  • CD10 -- follicle center.
  • BCL6 -- follicle center.
  • BCL2 -- normally negative in germinal centers (GCs), marks T cell; +ve in small B cell lymphomas.
  • MUM1 -- -ve in follicular lymphoma, +ve in DLBCL that did not arise from follicular lymphoma.

Plasma cell

  • Kappa -- usu. slightly stronger than lambda.
  • Lambda.
  • CD56[6] -- also +ve in NK/T cell lymphomas.
  • CD57 -- +ve in T-cell large granular lymphocytic leukemia.[7].
  • CD138.

Follicular dendritic cells

  • CD23 -- follicular dendritic cells.
  • CD21 -- follicular dendritic cells.

Hodgkin's lymphoma

Classic
  • CD30 +ve -- Hodgkin's lymphoma (most sensitive).
  • CD15 +ve.
  • PAX5 +ve.
  • EMA -ve.
  • EBER +ve/-ve.

Others:

  • CD20, CD45: weak +ve or -ve.
NLPHL
  • CD20 +ve.
  • CD30 -ve, CD15 -ve.
  • EMA +ve/-ve.
  • EBER -ve.

Others

  • Myeloperoxidase - in PMNs.
  • Glycophorin C.
  • CD61 -- megakaryocytes.
  • TdT.
  • CD34.

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.

Notes:

  • Large mononuclear cells are common (so called "mononuclear RSCs") but not diagnostic.

Images (classic HL):

Subtypes

There are four CHL subtypes:[8]

  1. Nodular sclerosis CHL - ~70% of CHL.
    • Mixed cellular background - T cell, plasma cells, eosinophils, neutrophils and histiocytes.
    • Nodular sclerosing fibrosis - thick strands fibrosis.
  2. Mixed cellularity CHL - ~20-25% of CHL.
    • Like nodular sclerosis - but no fibrosis.
    • May be associated with HIV infection.[9]
  3. Lymphocyte-rich CHL - rare.
    • T lymphocytes only (no mix of cells).
  4. Lymphocyte-depleted CHL - rare.
    • May be associated with HIV infection.[9]

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)[10]) - 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):

Small cell lymphomas

This grouping includes:

  • Follicular lymphoma.
  • Marginal zone lymphoma.
    • Nodal marginal zone lymphoma.
    • Extranodal marginal zone lymphoma (MALT lymphoma).
    • Splenic marginal zone lymphoma.
  • Mantle zone lymphoma.
  • Small lymphocytic lymphoma (SLL) / chronic lymphocytic leukemia (CLL).
  • Hairy cell leukemia.

Diffuse large B-cell lymphoma

General

  • Abbreviated DLBCL.

Microscopic

Features:[11]

  • 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.

Intravascular lymphoma

  • Rare.
  • Usually B-cell lineage (see below intravascular large B-cell lymphoma).
    • May be T-cell lineage.[12]

Intravascular large B-cell lymphoma

General

  • AKA angiotropic lymphoma, intravascular malignant lymphomatosis, malignant angioendotheliomatosis.
Clinical
  • Often a non-specific presentation.[13]
    • +/-Fever.
    • +/-Multiple infarcts.
    • +/-Non-specific skin lesions.

Microscopic

Features:

  • Abundant atypical intravascular lymphoid cells that are:
    • Large (~2-3X size of a mature lymphocyte or RBC).
    • Nucleolus prominent.

Notes:

  • It may be hard to find RBCs in the vessels.
  • Looks sorta like a DLBCL -- but is intravascular.

Images:

IHC

Features:[13]

  • CD20 +ve - key feature.
  • CD3 -ve.
  • CD34 -ve.

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.
  • Tumour cells:[15]
    • 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 myeloma.
  • 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:

Images:

DDx:

  • Neuroendocrine carcinoma - nucleus often has a plasmacytoid (plasma cell-like) appearance.

IHC

  • Kappa -- usu. slightly stronger than lambda.
  • Lambda.
  • CD56.[17]
    • Also +ve in NK/T cell lymphomas.
  • CD57.
    • Also +ve in T-cell large granular lymphocytic leukemia.[18].
  • CD138.
  • CD38. (???)

Molecular

  • t(4;14)(p16.3;q32.3) / IGH–MMSET.[19]
    • Assoc. with poor prognosis.[20]

Acute myeloid leukemia

General

  • May afflicits young adult.
  • Males>females.

Complications

  • Chloroma - soft tissue mass.
  • Leukostasis.
    • Occurs - lungs and brain.[21]
  • Hyperviscosity syndrome.
  • Spontaneous bleeding with low platelet counts.

Classification

There are two classifications:

  1. FAB (French-American-British) - based on histologic appearance/maturation.
  2. WHO classification.

Histology

Enteropathy-associated T cell lymphoma

General

  • Abbreviated EATL.
  • AKA enteropathy-type T cell lymphoma (ETTL).
  • T cell lymphoma due to celiac sprue.

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.

Primary mediastinal B-cell lymphoma

  • Abbreviated PMBL.
  • AKA primary mediastinal large B-cell lymphoma.

General

Features:[23][24]

  • Rare.
  • Young adults.

Microscopic

Features:

  • Similar to DLBCL.

Images:

Anaplastic large cell lymphoma

  • Abbreviated ALCL.

General

  • 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:Cite error: Invalid <ref> tag; refs with no name must have content

  • Large cells with eosinophilic cytoplasm.
  • Usually appear cohesive.
  • May be subcapsular.
  • "Wreath cells" - large (multinucleated) cells with (morphologically) one toroidal-shaped nucleus - key feature.
    • C-shaped nuclei may be present suggestive of wreath cells.
    • AKA "Hallmark cells". (???)
      • "Hallmark cells" = horseshoe-shaped or donut-shaped nucleus with an eosinophilic paranuclear region.[25][26])

IHC

Features:

  • CD30 +ve.
  • ALK-1 -ve/+ve; strongly supports ALCL Dx if +ve.
  • CD45 +ve.
  • CD4 +ve.
  • CD3 -ve/+ve.
  • CD7 -ve/+ve.
  • EMA +ve.

Molecular

  • t(2,5)(p23;q35)[27] - can be detected with FISH break apart probe.

Cutaneous T cell lymphoma

See Dermatologic neoplasms.

General

  • Abbreviated as CTCL.
    • Sézary syndrome is a subset of CTCL.

Microscopic

Features:[28]

  • Cerebriform nucleus (Sézary cell):[29]
    • Hyperchromatic.
    • "Convoluted" = twisted, coiled.[30]

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+[31] 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+[31] t(11;14)(q13;q32)[32] 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-[31] ??? indolent ??? common other small cell lymphomas, neuroendocrine tumours
Precursor B-cell lymphoblastic lymphoma/ leukemia small lymph node ??? ??? CD10+, CD5-, TdT+, CD99+[31] translocations ??? aggressive ??? uncommon small cell lymphomas
Hairy cell lymphoma small bone marrow, peripheral blood perinuclear clearing, clear cytoplasm, central nucleus CD25+, CD103+, CD5-[33] translocations ? splenomegaly, no lymphadenopathy, pancytopenia, good prognosis with Tx 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
Primary mediastinal B-cell lymphoma large (>2x RBC, often larger), variable size mediastinum histomorphology ? IHC ? translocations ? predominantly young adults, better prognosis than DLBCL uncommon DLBCL

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 large deep & subcapsular sinuses of LN eosinophilic cytoplasm, nucleoli, often cohesive, wreath cell (C-shaped nucleus) CD30+/-, Alk+/-, CD4+, CD3- t(2,5)(p23;q35)[27] clinical ? uncommon carcinoma
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

References

  1. 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.
  2. URL: http://www.ncbi.nlm.nih.gov/omim/601284. Accessed on: 31 August 2010.
  3. Pittaluga S, Wlodarska I, Pulford K, et al. (August 1997). "The monoclonal antibody ALK1 identifies a distinct morphological subtype of anaplastic large cell lymphoma associated with 2p23/ALK rearrangements". Am. J. Pathol. 151 (2): 343–51. PMC 1858018. PMID 9250148. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1858018/.
  4. URL: http://www.ncbi.nlm.nih.gov/omim/603518. Accessed on: 18 August 2010.
  5. URL: http://www.ncbi.nlm.nih.gov/omim/167414. Accessed on: 18 August 2010.
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  8. 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.
  9. 9.0 9.1 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.
  10. 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.
  11. 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.
  12. Wang L, Li C, Gao T (March 2010). "Cutaneous intravascular anaplastic large cell lymphoma". J Cutan Pathol. doi:10.1111/j.1600-0560.2010.01538.x. PMID 20337769.
  13. 13.0 13.1 13.2 Lapkuviene O, Forchetti D, Roepke JE (October 2001). "Unusual sites of involvement by hematologic malignancies. Case 1. Intravascular large B-cell lymphoma presenting with CNS symptoms". J. Clin. Oncol. 19 (19): 3988–91. PMID 11579120. http://jco.ascopubs.org/content/19/19/3988.full.
  14. URL: http://www.pathconsultddx.com/pathCon/diagnosis?pii=S1559-8675%2806%2970476-4. Accessed on: 27 October 2010.
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  16. URL: http://www.thefreelibrary.com/Dutcher+bodies+in+chronic+synovitis-a083551789. Accessed on: 4 August 2010.
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  18. URL: http://www.nature.com/bmt/journal/v33/n1/full/1704298a.html. Accessed on: 31 August 2010.
  19. Chesi, M.; Nardini, E.; Lim, RS.; Smith, KD.; Kuehl, WM.; Bergsagel, PL. (Nov 1998). "The t(4;14) translocation in myeloma dysregulates both FGFR3 and a novel gene, MMSET, resulting in IgH/MMSET hybrid transcripts.". Blood 92 (9): 3025-34. PMID 9787135.
  20. Keats, JJ.; Reiman, T.; Maxwell, CA.; Taylor, BJ.; Larratt, LM.; Mant, MJ.; Belch, AR.; Pilarski, LM. (Feb 2003). "In multiple myeloma, t(4;14)(p16;q32) is an adverse prognostic factor irrespective of FGFR3 expression.". Blood 101 (4): 1520-9. doi:10.1182/blood-2002-06-1675. PMID 12393535.
  21. AML. Harrison's 16th Ed.
  22. AG. 8 July, 2009.
  23. Johnson, PW.; Davies, AJ. (2008). "Primary mediastinal B-cell lymphoma.". Hematology Am Soc Hematol Educ Program: 349-58. doi:10.1182/asheducation-2008.1.349. PMID 19074109.
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  26. Ponzoni, M.; Terreni, MR.; Ciceri, F.; Ferreri, AJ.; Gerevini, S.; Anzalone, N.; Valle, M.; Pizzolito, S. et al. (Nov 2002). "Primary brain CD30+ ALK1+ anaplastic large cell lymphoma ('ALKoma'): the first case with a combination of 'not common' variants.". Ann Oncol 13 (11): 1827-32. PMID 12419758.
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  28. URL: http://emedicine.medscape.com/article/209091-overview. Accessed on: 19 August 2010.
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