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ORPHA:626

Large/giant congenital melanocytic nevus

high confidenceDisorder

Also known as: LGCMN · Large/giant CMN syndrome · Large/giant congenital pigmented nevus

Publications

2,308

88.1th percentile

Trials

1

Interventional, condition-specific

Researchers

1,014

Distinct authors in sample

Gene link

BRAF

Strong

Readiness

4/6

Stages with a signal

Clinical definition (Orphanet)

A rare skin hamartoma characterized by at least one pigmented skin lesion present at birth of more than 20 cm (large melanocytic nevus; LCMN) or 40 cm (giant; GCMN) projected adult diameter. The primary lesion is composed of mutated melanocytes and often locally disorganized epidermal annexes or dermis, and presents with an elevated risk of malignant transformation to melanoma or, more rarely, other neoplasms in skin or central nervous system.

How rare: 1-9 / 100 000 — about one to nine people per hundred thousand.

Orphanet entry

Cross-references

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

Additional Mondo synonyms (20)

Giant Congenital Melanocytic Nevus · bathing trunk nevus · congenital melanocytic nevi · congenital melanocytic nevus · congenital melanocytic nevus of skin · congenital melanocytic nevus of the skin · congenital nevus of skin · congenital nevus of the skin · congenital pigmented melanocytic Nevus · congenital pigmented nevus of skin · congenital pigmented nevus of the skin · congenital pigmented skin nevus · congenital skin nevus · giant congenital nevus · giant pigmented hairy nevus · giant pigmented nevus of skin · giant pigmented nevus of the skin · large congenital melanocytic nevus · melanocytic nevus syndrome, congenital, somatic · spitz nevus or nevus spilus, somatic

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.”

4/6 stages with a signal

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

  1. Gene identifiedPresent

    Strong — BRAF

  2. LiteraturePresent

    2,308 matched papers (1,178 in last 10 years) Source

  3. Phenotype characterisedPresent

    39 HPO annotations (e.g. Dry skin; Hypopigmented skin patches; Hypophosphatemic rickets) Source

  4. Animal modelNot found

    No Alliance genotype “model of” associations via Monarch for these Mondo IDs

  5. Orphan designationNot found

    No FDA or EMA orphan-drug designation matched this disease via UMLS or preferred name Source

  6. Interventional trialPresent

    1 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?

Yes — we know a specific gene responsible (BRAF).

GenCC classification: Strong.

Phenotypes (Monarch / HPO)

39

Associated phenotypes · MONDO:0044792

  • Dry skin
  • Hypopigmented skin patches
  • Hypophosphatemic rickets
  • Nevus
  • Pruritus

Showing 5 of 39 — open Monarch for the full list.

Animal models (Monarch / Alliance)

None returned for this Mondo ID. Empty here is not proof that no model organism work exists under another name or gene.

Monarch fetch 2026-07-29

Therapies

Designations, candidates, and chemicals

FDA OOPD and EMA orphan designations, Open Targets clinical candidates, and CTD chemical associations via MyDisease.info. These never change the interventional-trial headline.

Orphan designation (FDA · EMA)

No designation matched this disease via UMLS or preferred name on the FDA OOPD mirror or EMA orphan register. Absence here is not proof that none exists under another wording.

Open Targets candidates

1

Drugs / clinical candidates · MONDO_0044792

CTD chemicals (MyDisease.info)

No CTD chemical associations returned for this Mondo ID.

Literature

Is anyone studying this?

2,308

2,308 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=3967) is 59.

2,308 papers since the earliest indexed year in this search — median last-10-year count for a rare disease in this dataset is 59 (publications denominator n=3967).

1,178 in the last 10 years · high confidence · 88.1th percentile (publications denominator)

Phrase hits: 2,308 · MeSH hits: 0

Open Europe PMC search

Who's working on it?

1,014

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
    Gu J6 papers · 2026

    Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.

    Papers in Europe PMC
  2. 02
    Morimoto N6 papers · 2024

    Department of Plastic and Reconstructive Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.

    Papers in Europe PMC
  3. 03
    Sakamoto M6 papers · 2024

    Department of Plastic and Reconstructive Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.

    Papers in Europe PMC
  4. 04
    Tsuge I6 papers · 2024

    Department of Plastic and Reconstructive Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.

    Papers in Europe PMC
  5. 05
    Wang Y6 papers · 2026

    Department of Burns and Plastic Surgery, Beijing Children Hospital, National Center of Children's Health, Beijing Children Hospital, Capital Medical University, Beijing City, China. Electronic address: chinfjinf@163.com.

    Papers in Europe PMC
  6. 06
    Wei B6 papers · 2026

    Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.

    Papers in Europe PMC
  7. 07
    Xie F6 papers · 2026

    Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China. xiefenghe@163.com.

    Papers in Europe PMC
  8. 08
    Katsube M5 papers · 2024

    Department of Plastic and Reconstructive Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.

    Papers in Europe PMC
  9. 09
    Yamanaka H5 papers · 2024

    Department of Plastic and Reconstructive Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.

    Papers in Europe PMC
  10. 10
    Dai T4 papers · 2025

    Department of Wound Reconstructive Surgery, Tongji Hospital of Tongji University, Shanghai 200065, China. Electronic address: 15038689600@163.com.

    Papers in Europe PMC

Clinical research

Is a treatment being tested?

1

interventional trials for this specific condition

1 interventional trial matched this specific condition name; 1 currently recruiting in our sample. 1 trial are registered for melanocytic nevus, the broader category — shown separately because they may or may not enrol this specific subtype.

Data as of 11 September 2026

1 interventional trial — more than 77.2% of diseases in the trials denominator have none at all (5501 of 7126; this disease is at the 80.1th percentile).

high confidence · 80.1th percentile (trials denominator)

Recruiting interventional trials

From the matched ClinicalTrials.gov set

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

Broader category: melanocytic nevus

1

Interventional trials for the parent category, exclusive of NCT IDs already counted above. Eligibility for this subtype is not guaranteed.

Worth raising with a clinician. How we count trials.

Observational and natural-history studies

4 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

Other registries (secondary)

Broader net from EU CTIS, ISRCTN, and ICTRP when available — deduped against ClinicalTrials.gov IDs already counted above. Dual-model LLM relevance gates what we keep. These rows are not added to the interventional headline.

raw 0 · after dedupe 0 · already on CT.gov 0 · kept 0 · parent 0 · uncertain 0 · dropped 0 · fetched 2026-07-29

Source notes: ictrp: Error: ICTRP public search unavailable (WHO portal is SPA-only; SOAP needs partnership). Tried: https://apps.who.int/tri

No secondary-registry studies passed dual-model relevance for this condition name (after dedupe).

Where to find support

Condition-specific patient organisations, when Orphanet lists them, are on the disease’s Orphanet page. We also link umbrella groups that support undiagnosed and ultra-rare families.

Orphanet entry for Large/giant congenital melanocytic nevus — check Associations / patient organisations on that page.

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.

"Large/giant congenital melanocytic nevus" OR "LGCMN" OR "Large/giant CMN syndrome" OR "Large/giant congenital pigmented nevus" OR "Giant Congenital Melanocytic Nevus" OR "bathing trunk nevus" OR "congenital melanocytic nevi" OR "congenital melanocytic nevus" OR "congenital melanocytic nevus of skin" OR "congenital melanocytic nevus of the skin" OR "congenital nevus of skin" OR "congenital nevus of the skin" OR "congenital pigmented melanocytic Nevus" OR "congenital pigmented nevus of skin" OR "congenital pigmented nevus of the skin" OR "congenital pigmented skin nevus" OR "congenital skin nevus" OR "giant congenital nevus" OR "giant pigmented hairy nevus" OR "giant pigmented nevus of skin" OR "giant pigmented nevus of the skin" OR "large congenital melanocytic nevus" OR "melanocytic nevus syndrome, congenital, somatic" OR "spitz nevus or nevus spilus, somatic"

Run this search on Europe PMC

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

"Large/giant congenital melanocytic nevus" OR "LGCMN" OR "Large/giant CMN syndrome" OR "Large/giant congenital pigmented nevus" OR "Giant Congenital Melanocytic Nevus" OR "bathing trunk nevus" OR "congenital melanocytic nevi" OR "congenital melanocytic nevus" OR "congenital melanocytic nevus of skin" OR "congenital melanocytic nevus of the skin" OR "congenital nevus of skin" OR "congenital nevus of the skin" OR "congenital pigmented melanocytic Nevus" OR "congenital pigmented nevus of skin" OR "congenital pigmented nevus of the skin" OR "congenital pigmented skin nevus" OR "congenital skin nevus" OR "giant congenital nevus" OR "giant pigmented hairy nevus" OR "giant pigmented nevus of skin" OR "giant pigmented nevus of the skin" OR "large congenital melanocytic nevus" OR "melanocytic nevus syndrome, congenital, somatic" OR "spitz nevus or nevus spilus, somatic"

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

Study-type breakdown: 1 interventional · 4 observational · 0 expanded access. Only interventional studies enter the trial headline.

Parent-category trials query:

"melanocytic nevus"

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

Run this search on ClinicalTrials.gov

Confidence reasoning

  • Preferred label is multi-word and distinctive
  • No synonyms dropped by stoplist
  • No label/synonym collisions with other diseases in this corpus

Ingested 2026-07-26T14:36:36.257Z