Primary cutaneous marginal zone lymphoma
Haematolymphoid Tumours (WHO Classification, 5th ed.)
 | This page is under construction |
(General Instructions – The focus of these pages is the clinically significant genetic alterations in each disease type. This is based on up-to-date knowledge from multiple resources such as PubMed and the WHO classification books. The CCGA is meant to be a supplemental resource to the WHO classification books; the CCGA captures in a continually updated wiki-stye manner the current genetics/genomics knowledge of each disease, which evolves more rapidly than books can be revised and published. If the same disease is described in multiple WHO classification books, the genetics-related information for that disease will be consolidated into a single main page that has this template (other pages would only contain a link to this main page). Use HUGO-approved gene names and symbols (italicized when appropriate), HGVS-based nomenclature for variants, as well as generic names of drugs and testing platforms or assays if applicable. Please complete tables whenever possible and do not delete them (add N/A if not applicable in the table and delete the examples); to add (or move) a row or column in a table, click nearby within the table and select the > symbol that appears. Please do not delete or alter the section headings. The use of bullet points alongside short blocks of text rather than only large paragraphs is encouraged. Additional instructions below in italicized blue text should not be included in the final page content. Please also see Author_Instructions and FAQs as well as contact your Associate Editor or Technical Support.)
Primary Author(s)*
Molly Walkenhorst, DO and Shivani Golem, PhD, FACMG
WHO Classification of Disease
| Structure | Disease |
|---|---|
| Book | Haematolymphoid Tumours (5th ed.) |
| Category | B-cell lymphoid proliferations and lymphomas |
| Family | Mature B-cell neoplasms |
| Type | Marginal zone lymphoma |
| Subtype(s) | Primary cutaneous marginal zone lymphoma |
Definition / Description of Disease
Primary cutaneous marginal zone lymphoma (PCMZL) is an indolent non-Hodgkin lymphoma arising in skin without evidence of extracutaneous disease at the time of diagnosis. The tumor is comprised of monotypic, CD5-negative, CD10-positive neoplastic small B-cells with monotypic plasma cells, and a variable number of reactive T-cells infiltrating the dermis, often forming follicles with reactive germinal centers. Clonal immunoglobulin rearrangement may be present, thus determining the subtype as class-switched versus non-class-switched heavy-chain immunophenotype. There must be no evidence of extracutaneous disease at the time of diagnosis and other cutaneous lymphomas must be excluded.
Put your text here (Instructions: Brief description of approximately one paragraph - include disease context relative to other WHO classification categories, diagnostic criteria if applicable, and differential diagnosis if applicable. Other classifications can be referenced for comparison.)
Synonyms / Terminology
- Primary cutaneous marginal zone lymphoproliferative disorder (acceptable)
- Primary cutaneous immunocytoma (historical; no longer in use)
- Primary cutaneous plasmacytoma (historical; no longer in use)
Epidemiology / Prevalence
- 30-40% of all primary cutaneous B-cell lymphomas
- Predominantly affects adults in the fifth and sixth decades of life
- Male preponderance
- Unknown etiology in most cases
- Possible causes include chronic antigenic stimulation by intradermally applied antigens (e.g. tattoo pigments, vaccines, tick-borne bacteria, etc.)
- Association with Borrelia burgdorferi infection in endemic Europe but not associated in USA or Asia
- Patients tend to have increased gastrointestinal disorders and various autoimmune diseases as well
Clinical Features
- Present with multifocal or, less frequently, solitary red or violaceous plaques or nodules
Sites of Involvement
- Skin
- Most commonly on the trunk and arms
Morphologic Features
- Dense dermal infiltrate composed of:
- Small lymphocytes
- Plasma cells
- Located at periphery of lymphoid infiltrates or in subepidermal compartment
- Heavy chain immunophenotype show different morphologies:
- Non-class-switched forms
- Sheets of B-lymphocytes and few T-lymphocytes
- Scattered plasma cells
- Class-switched forms
- Large number of reactive T-lymphocytes but can occasionally be obscured by the neoplastic B cells
- Peripherally clustered monotypic plasma cells
- Non-class-switched forms
- Follicles with reactive germinal centers (most cases)
- clusters of plasmacytoid dendritic cells at periphery of infiltrates
Immunophenotype
- Neoplastic B cells have the following immunophenotype:
| Finding | Marker |
|---|---|
| Positive | CD20 |
| Positive | CD22 |
| Positive | CD79a |
| Positive | BCL2 |
| Negative | CD5 |
| Negative | CD10 |
| Negative | BCL6 |
| Negative | Cyclin D1 |
- Associated reactive germinal centers B cells
- BCL6 positive
- BCL2 negative
- Plasmacytoid dendritic cells
- CD123 positive
- Plasma cells
- CD138 and CD79a positive
- Plasma cells often have monotypic expression of immunoglobulin light chains
- The immunoglobulin heavy chain can be either non-class-switched or class-switched
- Non-class-switched heavy chain
- Produce IgM
- Positive for CXCR3 expression
- Approximately 10% of cases have IgM positivity
- Class-switched heavy chain
- Produce IgG, IgA, or IgE
- No expression of CXCR3
- Approximately 90% of cases have IgG, IgA, or IgE positivity
- Non-class-switched heavy chain
- IgG4 expressed by plasma cells in 13-35% of cases, though not related to IgG4-related disease.
WHO Essential and Desirable Genetic Diagnostic Criteria
(Instructions: The table will have the diagnostic criteria from the WHO book autocompleted; remove any non-genetics related criteria. If applicable, add text about other classification systems that define this entity and specify how the genetics-related criteria differ.)
| WHO Essential Criteria (Genetics)* | |
| WHO Desirable Criteria (Genetics)* | |
| Other Classification |
*Note: These are only the genetic/genomic criteria. Additional diagnostic criteria can be found in the WHO Classification of Tumours.
Related Terminology
(Instructions: The table will have the related terminology from the WHO autocompleted.)
| Acceptable | |
| Not Recommended |
Gene Rearrangements
Put your text here and fill in the table (Instructions: Details on clinical significance such as prognosis and other important information can be provided in the notes section. Please include references throughout the table. Do not delete the table.)
| Driver Gene | Fusion(s) and Common Partner Genes | Molecular Pathogenesis | Typical Chromosomal Alteration(s) | Prevalence -Common >20%, Recurrent 5-20% or Rare <5% (Disease) | Diagnostic, Prognostic, and Therapeutic Significance - D, P, T | Established Clinical Significance Per Guidelines - Yes or No (Source) | Clinical Relevance Details/Other Notes |
|---|---|---|---|---|---|---|---|
| EXAMPLE: ABL1 | EXAMPLE: BCR::ABL1 | EXAMPLE: The pathogenic derivative is the der(22) resulting in fusion of 5’ BCR and 3’ABL1. | EXAMPLE: t(9;22)(q34;q11.2) | EXAMPLE: Common (CML) | EXAMPLE: D, P, T | EXAMPLE: Yes (WHO, NCCN) | EXAMPLE:
The t(9;22) is diagnostic of CML in the appropriate morphology and clinical context (add reference). This fusion is responsive to targeted therapy such as Imatinib (Gleevec) (add reference). BCR::ABL1 is generally favorable in CML (add reference). |
| EXAMPLE: CIC | EXAMPLE: CIC::DUX4 | EXAMPLE: Typically, the last exon of CIC is fused to DUX4. The fusion breakpoint in CIC is usually intra-exonic and removes an inhibitory sequence, upregulating PEA3 genes downstream of CIC including ETV1, ETV4, and ETV5. | EXAMPLE: t(4;19)(q25;q13) | EXAMPLE: Common (CIC-rearranged sarcoma) | EXAMPLE: D | EXAMPLE:
DUX4 has many homologous genes; an alternate translocation in a minority of cases is t(10;19), but this is usually indistinguishable from t(4;19) by short-read sequencing (add references). | |
| EXAMPLE: ALK | EXAMPLE: ELM4::ALK
|
EXAMPLE: Fusions result in constitutive activation of the ALK tyrosine kinase. The most common ALK fusion is EML4::ALK, with breakpoints in intron 19 of ALK. At the transcript level, a variable (5’) partner gene is fused to 3’ ALK at exon 20. Rarely, ALK fusions contain exon 19 due to breakpoints in intron 18. | EXAMPLE: N/A | EXAMPLE: Rare (Lung adenocarcinoma) | EXAMPLE: T | EXAMPLE:
Both balanced and unbalanced forms are observed by FISH (add references). | |
| EXAMPLE: ABL1 | EXAMPLE: N/A | EXAMPLE: Intragenic deletion of exons 2–7 in EGFR removes the ligand-binding domain, resulting in a constitutively active tyrosine kinase with downstream activation of multiple oncogenic pathways. | EXAMPLE: N/A | EXAMPLE: Recurrent (IDH-wildtype Glioblastoma) | EXAMPLE: D, P, T | ||
Heavy and light chain immunoglobulin gene clonal rearrangements
Put your text here and fill in the table
| Chromosomal Rearrangement | Genes in Fusion (5’ or 3’ Segments) | Pathogenic Derivative | Prevalence | Diagnostic Significance (Yes, No or Unknown) | Prognostic Significance (Yes, No or Unknown) | Therapeutic Significance (Yes, No or Unknown) | Notes |
|---|---|---|---|---|---|---|---|
| EXAMPLE: t(9;22)(q34;q11.2) | EXAMPLE: 3'ABL1 / 5'BCR | EXAMPLE: der(22) | EXAMPLE: 20% (COSMIC)
EXAMPLE: 30% (add reference) |
Yes | No | Yes | EXAMPLE:
The t(9;22) is diagnostic of CML in the appropriate morphology and clinical context (add reference). This fusion is responsive to targeted therapy such as Imatinib (Gleevec) (add reference). |
Individual Region Genomic Gain/Loss/LOH
None
| Chr # | Gain, Loss, Amp, LOH | Minimal Region Cytoband and/or Genomic Coordinates [Genome Build; Size] | Relevant Gene(s) | Diagnostic, Prognostic, and Therapeutic Significance - D, P, T | Established Clinical Significance Per Guidelines - Yes or No (Source) | Clinical Relevance Details/Other Notes |
|---|---|---|---|---|---|---|
Characteristic Chromosomal or Other Global Mutational Patterns
None
| Chromosomal Pattern | Molecular Pathogenesis | Prevalence -
Common >20%, Recurrent 5-20% or Rare <5% (Disease) |
Diagnostic, Prognostic, and Therapeutic Significance - D, P, T | Established Clinical Significance Per Guidelines - Yes or No (Source) | Clinical Relevance Details/Other Notes |
|---|---|---|---|---|---|
Gene Mutations (SNV/INDEL)
Put your text here and fill in the table (Instructions: This table is not meant to be an exhaustive list; please include only genes/alterations that are recurrent or common as well either disease defining and/or clinically significant. If a gene has multiple mechanisms depending on the type or site of the alteration, add multiple entries in the table. For clinical significance, denote associations with FDA-approved therapy (not an extensive list of applicable drugs) and NCCN or other national guidelines if applicable; Can also refer to CGC workgroup tables as linked on the homepage if applicable as well as any high impact papers or reviews of gene mutations in this entity. Details on clinical significance such as prognosis and other important information such as concomitant and mutually exclusive mutations can be provided in the notes section. Please include references throughout the table. Do not delete the table.)
| Gene | Genetic Alteration | Tumor Suppressor Gene, Oncogene, Other | Prevalence -
Common >20%, Recurrent 5-20% or Rare <5% (Disease) |
Diagnostic, Prognostic, and Therapeutic Significance - D, P, T | Established Clinical Significance Per Guidelines - Yes or No (Source) | Clinical Relevance Details/Other Notes |
|---|---|---|---|---|---|---|
| EXAMPLE:EGFR
|
EXAMPLE: Exon 18-21 activating mutations | EXAMPLE: Oncogene | EXAMPLE: Common (lung cancer) | EXAMPLE: T | EXAMPLE: Yes (NCCN) | EXAMPLE: Exons 18, 19, and 21 mutations are targetable for therapy. Exon 20 T790M variants cause resistance to first generation TKI therapy and are targetable by second and third generation TKIs (add references). |
| EXAMPLE: TP53; Variable LOF mutations
|
EXAMPLE: Variable LOF mutations | EXAMPLE: Tumor Supressor Gene | EXAMPLE: Common (breast cancer) | EXAMPLE: P | EXAMPLE: >90% are somatic; rare germline alterations associated with Li-Fraumeni syndrome (add reference). Denotes a poor prognosis in breast cancer. | |
| EXAMPLE: BRAF; Activating mutations | EXAMPLE: Activating mutations | EXAMPLE: Oncogene | EXAMPLE: Common (melanoma) | EXAMPLE: T | ||
Note: A more extensive list of mutations can be found in cBioportal, COSMIC, and/or other databases. When applicable, gene-specific pages within the CCGA site directly link to pertinent external content.
| Gene; Genetic Alteration | Presumed Mechanism (Tumor Suppressor Gene [TSG] / Oncogene / Other) | Prevalence (COSMIC / TCGA / Other) | Concomitant Mutations | Mutually Exclusive Mutations | Diagnostic Significance (Yes, No or Unknown) | Prognostic Significance (Yes, No or Unknown) | Therapeutic Significance (Yes, No or Unknown) | Notes |
|---|---|---|---|---|---|---|---|---|
| FAS (CD95) gene mutation | Apoptosis regulator | >60% of cases | Suggests that apoptosis defect underlies the pathogenesis of PCMZL | |||||
| SLAMF1 somatic mutation | ||||||||
| SPEN somatic mutation | ||||||||
| NCOR2 somatic mutation |
Note: A more extensive list of mutations can be found in cBioportal (https://www.cbioportal.org/), COSMIC (https://cancer.sanger.ac.uk/cosmic), ICGC (https://dcc.icgc.org/) and/or other databases. When applicable, gene-specific pages within the CCGA site directly link to pertinent external content.
Epigenomic Alterations
None
Genes and Main Pathways Involved
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| Gene; Genetic Alteration | Pathway | Pathophysiologic Outcome |
|---|---|---|
| EXAMPLE: BRAF and MAP2K1; Activating mutations | EXAMPLE: MAPK signaling | EXAMPLE: Increased cell growth and proliferation |
| EXAMPLE: CDKN2A; Inactivating mutations | EXAMPLE: Cell cycle regulation | EXAMPLE: Unregulated cell division |
| EXAMPLE: KMT2C and ARID1A; Inactivating mutations | EXAMPLE: Histone modification, chromatin remodeling | EXAMPLE: Abnormal gene expression program |
Genetic Diagnostic Testing Methods
Put your text here (Instructions: Include recommended testing type(s) to identify the clinically significant genetic alterations.)
Familial Forms
Put your text here (Instructions: Include associated hereditary conditions/syndromes that cause this entity or are caused by this entity.)
Additional Information
- Favorable prognosis
- 5-year disease-specific survival rate >98%
- Recurrence is common
- 4% of patients will have extracutaneous spread, particularly in patients with longstanding multifocal disease
Links
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References
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Notes
*Primary authors will typically be those that initially create and complete the content of a page. If a subsequent user modifies the content and feels the effort put forth is of high enough significance to warrant listing in the authorship section, please contact the Associate Editor or other CCGA representative. When pages have a major update, the new author will be acknowledged at the beginning of the page, and those who contributed previously will be acknowledged below as a prior author.
Prior Author(s):
*Citation of this Page: “Primary cutaneous marginal zone lymphoma”. Compendium of Cancer Genome Aberrations (CCGA), Cancer Genomics Consortium (CGC), updated 02/13/2025, https://ccga.io/index.php/HAEM5:Primary_cutaneous_marginal_zone_lymphoma.