A plain-language guide

multiple endocrine neoplasia type 2

What's known, what's still uncertain, and what's actively debated, written plainly, and built only from published medical research.

Early map · 11 sourced statements Every statement names its source Updated 2026-08-04
Please read this first. This guide is a companion to your medical team, not a replacement, and it is not medical advice. Everything here is tied to published research. If something you expected is not here, it almost always means we have not mapped a source for it yet, not that it is unknown to medicine. multiple endocrine neoplasia type 2 is an early, growing map, so it will look incomplete on purpose: we would rather show less and have every line be something you can check than fill the page with claims we cannot stand behind. For anything about your own situation, your clinicians hold the full picture. How this guide is built and why.

What's multiple endocrine neoplasia type 2?

Multiple endocrine neoplasia type 2 is a rare inherited tumour syndrome caused by changes in the RET gene.

Also indexed asORPHA:653, MONDO:0019003
Features mapped8
Treatments mapped1
Published sources8
Last reviewed2026-08-04

Signs and symptoms

Medullary thyroid carcinoma

Medullary thyroid carcinoma, the core cancer of MEN2, usually shows up as a lump in the thyroid, with or without swollen lymph nodes, and sometimes with diarrhea or signs that it has spread.

Limited evidenceSource: PMID:41614693
Evidence ratingweak
Study designontology_import
Confidence (0-1)0.7
Replicationunreplicated
Supporting sourcesORPHA:653
Notesplain_language confirmed from PMID:41614693 via curation 2026-07-27 [Carrie Schluter, BCPA]. | regrounded primary ORPHA:653 -> PMID:41614693 on 2026-07-27 [Carrie Schluter, BCPA]
Last reviewed2026-07-27

Multiple mucosal neuromas

In MEN2B, benign nerve growths called mucosal neuromas form in the mouth, part of a classic pattern that also includes a tall, long-limbed build and eye and palate changes.

Limited evidenceSource: PMID:41961175
Evidence ratingweak
Study designontology_import
Confidence (0-1)0.7
Replicationunreplicated
Supporting sourcesORPHA:653
Notesplain_language confirmed from PMID:41961175 via curation 2026-07-27 [Carrie Schluter, BCPA]. | regrounded primary ORPHA:653 -> PMID:41961175 on 2026-07-27 [Carrie Schluter, BCPA]
Last reviewed2026-07-27

Pheochromocytoma

Multiple endocrine neoplasia type 2A involves medullary thyroid carcinoma and, less often, pheochromocytoma, a tumour of the adrenal gland, or overactive parathyroid glands, or both. Rarely it also involves a skin condition called cutaneous lichen amyloidosis or Hirschsprung's disease.

Limited evidenceSource: PMID:40102258
Evidence ratingweak
Study designontology_import
Confidence (0-1)0.7
Replicationunreplicated
Supporting sourcesORPHA:653
Notesplain_language confirmed from PMID:40102258 via curation 2026-07-27 [llm:fable-5]. | regrounded primary ORPHA:653 -> PMID:40102258 on 2026-07-27 [Carrie Schluter, BCPA]
Last reviewed2026-07-27

Parathyroid adenoma

Multiple endocrine neoplasia type 2 involves several tumours, including pheochromocytoma and parathyroid adenoma. Medullary thyroid carcinoma is the one most people with the condition go on to develop.

Limited evidenceSource: PMID:29348307
Evidence ratingweak
Study designontology_import
Confidence (0-1)0.7
Replicationunreplicated
Supporting sourcesORPHA:653
Notesplain_language confirmed from PMID:29348307 via curation 2026-07-27 [llm:fable-5]. | regrounded primary ORPHA:653 -> PMID:29348307 on 2026-07-27 [Carrie Schluter, BCPA]
Last reviewed2026-07-27

Hypercalcemia

High calcium in the blood is a common feature of multiple endocrine neoplasia type 2A, arising from overactive parathyroid glands.

Limited evidenceSource: PMID:41938302
Evidence ratingweak
Study designontology_import
Confidence (0-1)0.7
Replicationunreplicated
Supporting sourcesORPHA:653
Notesplain_language confirmed from PMID:41938302 via curation 2026-07-27 [llm:fable-5]. | regrounded primary ORPHA:653 -> PMID:41938302 on 2026-07-27 [Carrie Schluter, BCPA]
Last reviewed2026-07-27

Constipation

Persistent constipation, along with unusually flexible joints, is part of the wider picture of multiple endocrine neoplasia type 2B, alongside medullary thyroid carcinoma appearing early and pheochromocytoma appearing later.

Limited evidenceSource: PMID:39148481
Evidence ratingweak
Study designontology_import
Confidence (0-1)0.7
Replicationunreplicated
Supporting sourcesORPHA:653
Notesplain_language confirmed from PMID:39148481 via curation 2026-07-27 [llm:fable-5]. | regrounded primary ORPHA:653 -> PMID:39148481 on 2026-07-27 [Carrie Schluter, BCPA]
Last reviewed2026-07-27

Diarrhea

Medullary thyroid carcinoma usually shows up as a lump in the thyroid, with or without swollen lymph nodes. Less often it brings diarrhea or symptoms from spread elsewhere in the body.

Limited evidenceSource: PMID:41614693
Evidence ratingweak
Study designontology_import
Confidence (0-1)0.7
Replicationunreplicated
Supporting sourcesORPHA:653
Notesplain_language confirmed from PMID:41614693 via curation 2026-07-27 [llm:fable-5]. | regrounded primary ORPHA:653 -> PMID:41614693 on 2026-07-27 [Carrie Schluter, BCPA]
Last reviewed2026-07-27

Ganglioneuromatosis

Ganglioneuromatosis, an overgrowth of benign nerve tissue in the intestine, was present in every case in one reported series of multiple endocrine neoplasia type 2B.

Limited evidenceSource: PMID:39148481
Evidence ratingweak
Study designontology_import
Confidence (0-1)0.7
Replicationunreplicated
Supporting sourcesORPHA:653
Notesplain_language confirmed from PMID:39148481 via curation 2026-07-27 [llm:fable-5]. | regrounded primary ORPHA:653 -> PMID:39148481 on 2026-07-27 [Carrie Schluter, BCPA]
Last reviewed2026-07-27

Treatment and management

What the research describes, not a recommendation. Treatment decisions belong with your clinician.

This covers treatments that appear in the published research mapped here. Investigational and experimental therapies are not included, so their absence is a boundary of this map, not a sign they do not exist.

prophylactic thyroidectomy

Removing the thyroid gland before cancer develops (prophylactic thyroidectomy), guided by RET genetic screening in affected families, is an effective treatment approach.

Used to help with: Multiple endocrine neoplasia type 2.

Limited evidenceSource: PMID:26974132
The source text this rests on
“In the recent decades (from 1993) the diagnosis of asymptomatic child carrying RET mutations in the affected families by MTC, has been provided by genetic screening, and prophylactic thyroidectomy is an efficacy therapeutic procedure.”
An excerpt quoted verbatim from the source named above, shown as recorded. The full sentence is in the linked source.
Evidence ratingweak
Confidence (0-1)0.7
Replicationunreplicated
Notesconfirmed from PMID:26974132 via curation 2026-07-27
Last reviewed2026-07-27

How to read the evidence labels

Widely acceptedSpecialists broadly agree on this.
Strong evidenceBacked by solid, repeated research.
Moderate evidenceReasonable evidence, still being confirmed.
Limited evidenceSome evidence, but not yet convincing.
Early evidenceAn early finding that needs more study.
Experts disagreeResearchers actively disagree about this.
No longer supportedLater, stronger evidence or guidance overturned this.

Where this comes from

This guide is built from 8 published source(s). Every claim above links back to one of them. Click any source ID to read the original on PubMed.

PMID:26974132 · Medullary thyroid carcinoma: a review on ethical considerations in treatment of children.
PMID:29348307 · Non-mammalian models of multiple endocrine neoplasia type 2.
PMID:39148481 · Clues for Early Diagnosis of MEN2B Syndrome Before Medullary Thyroid Carcinoma.
PMID:39404342 · Genotype/phenotype correlations in multiple endocrine neoplasia type 2.
PMID:40102258 · Hereditary Medullary Thyroid Cancer: Genotype-Phenotype Correlation.
PMID:41614693 · Atypical presentation and association of medullary thyroid carcinoma: reports from a tertiary care center in Northwest India.
PMID:41938302 · Sarcoidosis-Induced Hypercalcemia in a Patient With Multiple Endocrine Neoplasia Type 2A (MEN2A) Syndrome Harboring the C609Y REarranged During Transfection (RET) Mutation.
PMID:41961175 · The clinical consequences of diagnostic delay in sporadic pediatric MEN2B: a case series of 6 children.

Take it further

Printed, source-linked documents built from this condition's graph — ready to bring to an appointment or attach to a coverage request. Every claim carries its published source, the same as this guide.