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ORPHA:98842

Lymphomatoid papulosis

low confidenceDisorder

Also known as: LyP

Publications

1,940

Trials

5

Interventional, condition-specific

Researchers

995

Distinct authors in sample

Gene link

—

Readiness

2/6

Stages with a signal

Clinical definition (Orphanet)

Lymphomatoid papulosis (LyP) is a rare cutaneous condition characterized by chronic, recurrent, and self-regressing papulonodular skin eruptions. It belongs to the spectrum of primary cutaneous CD30+ lymphoproliferative disorders, along with primary cutaneous anaplastic large cell lymphoma (primary C-ALCL) with which it shares overlapping clinical and histopathologic features.

How rare: How common this is has not been clearly measured.

Orphanet entry

Cross-references

Joined from Mondo / Orphanet. MeSH labels may enter searches; UMLS / OMIM / NCIT are stored for reference.

Research stages

Trial readiness signals

Where this condition sits on an open-data research pipeline — not how close a treatment is, and not medical advice. Empty stages often mean “not in these databases under this Mondo ID,” not “impossible.”

2/6 stages with a signal

An interventional trial matched this condition name on ClinicalTrials.gov — see trials below.

  1. Gene identifiedNot found

    No GenCC disease–gene assertion in this build

  2. LiteraturePresent

    1,940 matched papers (835 in last 10 years) Source

  3. Phenotype characterisedNot checked

    Not yet enriched from Monarch / HPO

  4. Animal modelNot checked

    Not yet enriched from Monarch / Alliance

  5. Orphan designationNot checked

    FDA/EMA orphan-drug designation not enriched yet

  6. Interventional trialPresent

    5 matched on ClinicalTrials.gov (1 recruiting in sample)

Biology

Genes and phenotypes

Gene–disease validity from GenCC, plus phenotypes and animal models joined from Monarch Initiative via Mondo ID — not a clinical diagnosis aid.

Do we know what causes it?

Not yet — the cause hasn't been pinned down in GenCC.

No strong gene–disease assertion joined for this Orphanet entity.

Phenotypes (Monarch / HPO)

Not enriched in this build — Monarch phenotype joins were not run for this record.

Animal models (Monarch / Alliance)

Not enriched in this build.

Literature

Is anyone studying this?

1,940

1,940 papers have been published on this condition. That is a real research literature — still far smaller than common diseases (breast cancer: over 700,000 papers). Median papers in the last 10 years for a rare disease in this dataset (publications denominator n=5449) is 41.

1,940 papers since the earliest indexed year in this search — median last-10-year count for a rare disease in this dataset is 41 (publications denominator n=5449).

835 in the last 10 years · low confidence

Phrase hits: 1,940 · MeSH hits: 22

Open Europe PMC search

Who's working on it?

995

Distinct author names in 200 sampled papers — named people below.

Who's working on it?

People publishing on this condition (sampled Europe PMC records). Affiliation is the most recent found in that sample.

  1. 01
    Geskin LJ5 papers · 2025

    Department of Dermatology, Columbia University Irving Medical Center, New York, New York.

    Papers in Europe PMC
  2. 02
    Berti E4 papers · 2025

    Pathology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, 20154, Milan, Italy.

    Papers in Europe PMC
  3. 03
    Chahud F4 papers · 2026

    Department of Pathology and Forensic Medicine, Ribeirão Preto Medical School (FMRP/USP), University of São Paulo, Ribeirão Preto, São Paulo, Brazil.

    Papers in Europe PMC
  4. 04
    Kempf W4 papers · 2025

    Kempf Und Pfaltz Histologische Diagnostik, University of Zurich, Department of Dermatology, Zurich, Switzerland.

    Papers in Europe PMC
  5. 05
    Lee WJ4 papers · 2025

    Department of Dermatology, Asan Medical Center, University of Ulsan College of Medicine, 88, Songpa-gu, Seoul, Korea. Electronic address: uucm79@hanmail.net.

    Papers in Europe PMC
  6. 06
    León JE4 papers · 2026

    Oral Pathology, Department of Stomatology, Public Oral Health, and Forensic Dentistry, Ribeirão Preto Dental School (FORP/USP), University of São Paulo, Ribeirão Preto, São Paulo, Brazil; and.

    Papers in Europe PMC
  7. 07
    Magro CM4 papers · 2025

    Department of Pathology and Laboratory Medicine Weill Cornell Medicine New York NY USA.

    Papers in Europe PMC
  8. 08
    Mitteldorf C4 papers · 2025

    Department of Dermatology, Venereology and Allergology, University Medical Center Göttingen, Göttingen, Germany.

    Papers in Europe PMC
  9. 09
    Pileri A4 papers · 2026

    Dermatology Unit, IRCCS of Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy.

    Papers in Europe PMC
  10. 10
    Schreidah CM4 papers · 2025

    Columbia University Vagelos College of Physicians and Surgeons, New York, New York.

    Papers in Europe PMC

Clinical research

Is a treatment being tested?

5

interventional trials for this specific condition

5 interventional trials matched this specific condition name; 1 currently recruiting in our sample.

Data as of 27 July 2026

5 interventional trials — more than 73% of diseases in the trials denominator have none at all (5114 of 7003; this disease is at the 87.9th percentile).

low confidence · 87.9th percentile (trials denominator)

Recruiting interventional trials

From the matched ClinicalTrials.gov set

5 interventional trials matched after quoted-phrase search and title/condition post-filter.

Observational and natural-history studies

2 observational studies match this condition. These do not test a treatment and are not counted in the interventional-trial headline, but they are genuine research: natural-history work often defines the endpoints needed for a future rare-disease trial, and families may be able to enroll.

Recruiting or not-yet-recruiting

Open the complete matched search on ClinicalTrials.gov

Where to find support

We do not yet link condition-specific patient organisations. These umbrella groups support undiagnosed and ultra-rare families:

India — NPRD

Last verified 2026-07-26

This ORPHAcode is not on our curated NPRD list (direct or Mondo-parent match). That does not decide clinical eligibility; families in India should ask a notified Centre of Excellence about current coverage.

Hand-curated for this project. ORPHAcode mappings are best-effort and may be incomplete or imprecise for umbrella categories. Parent (Mondo) matches mean the policy lists a broader category — confirm eligibility with a Centre of Excellence. Financial entitlements summarised from public policy statements and may change. This is not official government guidance.

How we counted this

Europe PMC query (preferred label + any corrected label + Orphanet and Mondo exact synonyms, stoplisted; unioned with resolved MeSH labels when available). UMLS / OMIM / NCIT cross-references are stored on the overview but are not added to the query string.

"Lymphomatoid papulosis"

Run this search on Europe PMC

MeSH descriptor terms unioned into the query: Lymphomatoid Papulosis

ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):

"Lymphomatoid papulosis"

Interventional trials matched via: both (mesh = registered under a MeSH descriptor no name phrase would catch; recall-expansion = gene / selected parent terms used only for trials).

Study-type breakdown: 5 interventional · 2 observational · 0 expanded access. Only interventional studies enter the trial headline.

Query health: ok — strategies attempted: phrase, mesh; with hits: phrase, mesh

Run this search on ClinicalTrials.gov

Synonyms dropped by stoplist: LyP

Confidence reasoning

  • Preferred label is multi-word and distinctive
  • 1 synonym(s) dropped by stoplist (may under-count)
  • No label/synonym collisions with other diseases in this corpus
  • Publication count (1940) is extremely high with unknown/missing prevalence — treat as possible over-matching, not proven research intensity

Ingested 2026-07-27T05:33:48.327Z