# Primary cutaneous marginal zone lymphoma

Source: https://onco.cc/cancers/primary-cutaneous-marginal-zone-lymphoma/  
OnCo record `primary-cutaneous-marginal-zone-lymphoma` (Cancer). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

Primary cutaneous marginal zone lymphoma is a very slow-growing lymphoma that appears as pink or purple lumps in the skin, usually on the arms or trunk, and almost never spreads inside the body. WHO-HAEM5 now calls it a lymphoproliferative disorder because it behaves so well; surgery or radiotherapy clears most lesions, and relapses in the skin are common but harmless.

## Summary

WHO-HAEM5 renamed this entity primary cutaneous marginal zone lymphoproliferative disorder to reflect its indolent behaviour, keeping it beside the other marginal zone lymphomas; it was once called immunocytoma because of its plasmacytic differentiation (Alaggio 2022). In 137 patients, 51 percent had a solitary lesion, 29 percent regional and 20 percent generalised skin disease; surgical excision, local radiotherapy or both were the initial treatment in 86 percent, complete remission followed in 88 percent (93 percent of solitary or localised and 71 percent of multifocal cases), and cutaneous relapses occurred in 44 percent without loss of survival (J Am Acad Dermatol 2013). Unlike other marginal zone lymphomas, 39 percent of primary cutaneous cases with plasmacytic differentiation express IgG4, the highest rate in any B-cell lymphoma, against 1 of 120 non-cutaneous cases (Modern Pathology 2013).

How it differs from its parent: it is confined to the skin at diagnosis, is treated by dermatologists with excision or radiotherapy rather than systemic therapy, and its relapses are skin-only; extracutaneous spread is the exception. Borrelia infection has been implicated in some European cases.

How common: no registry share in the sources read.

Treatment: excision or low-dose radiotherapy for solitary or localised lesions; observation, intralesional steroids or rituximab for multifocal disease; systemic therapy only for the rare extracutaneous spread, following the parent page (J Am Acad Dermatol 2013; Zucca 2020).

## Fields

- Kind: Cancer
- Last checked: 2026-09-24
- Also known as: Primary cutaneous marginal zone B-cell lymphoma; Primary cutaneous marginal zone lymphoproliferative disorder; Primary cutaneous immunocytoma; Cutaneous immunocytoma; PCMZL
- Tags: subtype-page; wave4; haematologic; rare
- Group: haematologic
- Burden: Rare and indolent; the largest clinical series holds 137 patients, 51 percent presenting with a solitary lesion (J Am Acad Dermatol 2013). No registry share is in the sources read.
- Subtypes: Primary cutaneous marginal zone lymphoproliferative disorder, solitary lesion (half of cases); Multifocal or generalised cutaneous disease; Class-switched (IgG4-expressing) cutaneous marginal zone lymphoma; Borrelia-associated cutaneous marginal zone lymphoma (Europe)
- Biomarkers: Plasmacytic differentiation with light chain restriction; IgG4 expression (39 percent); Staging to exclude extracutaneous disease; Borrelia serology in endemic areas

## Sections of this record

The page is a hub with ten sections in reading order; large sections have their own page. The same plan as JSON: https://onco.cc/api/v1/cancers/primary-cutaneous-marginal-zone-lymphoma/sections.json

- Overview (on the hub): The TL;DR, the family this cancer belongs to, the organ, who gets it and what the state of the art is. https://onco.cc/cancers/primary-cutaneous-marginal-zone-lymphoma/#overview
- What it is (on the hub): Anatomy, the subtypes and how they differ, how it is staged, and where advanced disease spreads. https://onco.cc/cancers/primary-cutaneous-marginal-zone-lymphoma/#what-it-is [4 subtypes]
- Finding it (on the hub): How it shows itself, how it is confirmed, what screening exists, and the biomarkers clinicians test for. https://onco.cc/cancers/primary-cutaneous-marginal-zone-lymphoma/#finding-it [4 biomarkers]
- Treating it (on the hub): The standard of care by setting, the medicines, surgery and radiotherapy named in it, and the regimens behind them. https://onco.cc/cancers/primary-cutaneous-marginal-zone-lymphoma/#treating-it [2 settings]
- Evidence (on the hub): Trials recruiting now, the landmark trials, the key papers and what they mean, the latest literature, and the milestones year by year. https://onco.cc/cancers/primary-cutaneous-marginal-zone-lymphoma/#evidence
- The science (on the hub): The molecular landscape: the targets and how often each appears, the pathways, the mechanics stages and the preclinical models. https://onco.cc/cancers/primary-cutaneous-marginal-zone-lymphoma/#science [1 target]
- Where you are (own page): Cases by country, the UK and NHS pathway and other country lenses, and the expert centres with trials on record. https://onco.cc/cancers/primary-cutaneous-marginal-zone-lymphoma/where-you-are/
- Living with it (on the hub): The decisions you may face, the aids that walk through them, the warnings on record, the first sixty days and the questions to ask. https://onco.cc/cancers/primary-cutaneous-marginal-zone-lymphoma/#living-with-it [9 questions, 2 red cards]
- What is coming (own page): Everything in development, the open problems and what is being done about them, the roadmaps, and what changed on this record. https://onco.cc/cancers/primary-cutaneous-marginal-zone-lymphoma/coming/ [1 medicine]
- Data (own page): Every connected record, the notes, the JSON, Markdown and RDF twins, and where the record came from and when it was checked. https://onco.cc/cancers/primary-cutaneous-marginal-zone-lymphoma/data/ [8 connected records]

## Standard of care

- Solitary or localised: Excision or low-dose radiotherapy. ([Marginal zone lymphoma](https://onco.cc/cancers/marginal-zone-lymphoma/))
- Multifocal: Observation, intralesional steroids or rituximab; systemic therapy only for extracutaneous spread. ([Rituximab](https://onco.cc/drugs/rituximab/), [Marginal zone lymphoma](https://onco.cc/cancers/marginal-zone-lymphoma/))

## Sources

- Wikipedia: https://en.wikipedia.org/wiki/Primary_cutaneous_marginal_zone_lymphoma
- Alaggio 2022, Leukemia: the 5th edition WHO classification of haematolymphoid tumours, lymphoid neoplasms: https://doi.org/10.1038/s41375-022-01620-2
- J Am Acad Dermatol 2013: primary cutaneous marginal zone B-cell lymphoma, 137 patients: https://doi.org/10.1016/j.jaad.2013.04.047
- Modern Pathology 2013: IgG4 expression in primary cutaneous marginal zone lymphomas: https://doi.org/10.1038/modpathol.2013.106
- Zucca 2020, Annals of Oncology: marginal zone lymphomas, ESMO clinical practice guidelines: https://doi.org/10.1016/j.annonc.2019.10.010

## Connected records

- cancers: [Cutaneous T-cell lymphoma (mycosis fungoides and Sezary syndrome)](https://onco.cc/cancers/cutaneous-t-cell-lymphoma/), [Extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma)](https://onco.cc/cancers/malt-lymphoma/), [Marginal zone lymphoma](https://onco.cc/cancers/marginal-zone-lymphoma/), [Primary cutaneous follicle centre lymphoma](https://onco.cc/cancers/primary-cutaneous-follicle-centre-lymphoma/), [Sezary syndrome](https://onco.cc/cancers/sezary-syndrome/)
- drugs: [Rituximab](https://onco.cc/drugs/rituximab/)

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JSON: https://onco.cc/api/v1/entities/primary-cutaneous-marginal-zone-lymphoma.json