> Trialight public data. Index of pages: https://trialight.com/llms.txt
> Web page: https://trialight.com/data/condition/megalencephaly-capillary-malformation-polymicrogyria-bdb633c9-b679-56f0-8567-84274663c5fe
> Record changed: 2026-10-13

# Megalencephaly-capillary malformation-polymicrogyria syndrome

Therapeutic area

Neurology

Rare disease

Yes

## Definition and classification

**Definition**

A polymalfomative syndrome characterized by cutaneous capillary malformations, megalencephaly, cortical brain malformations (most distinctively polymicrogyria), abnormalities of somatic growth with body and brain asymmetry, developmental delay, and characteristic facial dysmorphism.

**Genetic basis**

Yes

**Non-human condition**

No

**Rare disease**

Yes

**Listing at source**

Listed

**Condition name**

Megalencephaly-capillary malformation-polymicrogyria syndrome

**Therapeutic area**

Neurology

### Alternative names (15)

- megalencephaly-capillary malformation-polymicrogyria syndrome
- MCAP
- MCM
- MCMTC
- macrocephaly-capillary malformation syndrome
- macrocephaly-cutis marmorata telangiectatica congenita syndrome
- megalencephaly-capillary malformation syndrome
- megalencephaly-capillary malformation-polymicrogyria syndrome
- megalencephaly-capillary malformation-polymicrogyria syndrome, somatic
- megalencephaly-cutis marmorata telangiectatica congenita syndrome
- M-CM
- M-CMTC
- macrocephaly cutis marmorata telangiectatica congenita
- megalencephaly cutis marmorata telangiectatica congenita
- megalocephaly cutis marmorata telangiectatica congenita

## Clinical profile

**All therapeutic areas**

- Neurology

**Severity**

Severe

### Disease mechanisms (3)

- Developmental
- Genetic
- Hereditary

## Identifiers

**MONDO ID**

MONDO:0011240

Source: [monarchinitiative.org](https://monarchinitiative.org/MONDO:0011240)

**Parent condition**

MONDO:0100283

## Related records

### Broader conditions (15)

- Central nervous system malformation
- Developmental defect during embryogenesis
- Disease
- Disease by body system or component
- Disease by developmental or physiological process
- Disease by etiologic mechanism
- Disease of genetic or genomic mechanism
- Disorder of development or morphogenesis
- Hereditary disease
- Hereditary neurological disease
- Human disease
- Nervous system disorder
- Overgrowth syndrome
- Overgrowth syndrome and/or cerebral malformations due to abnormalities in MTOR pathway genes
- [PIK3CA-related overgrowth spectrum](https://trialight.com/data/condition/pik3ca-related-overgrowth-spectrum-57d09a23-7b5d-57e6-913a-33978ba94aa8.md)

### Trials (4)

- [A Phase 2 Study of Mutant-selective PI3Kα Inhibitor, RLY-2608, in Adults and Children With PIK3CA Related Overgrowth Spectrum and Malformations Driven by PIK3CA Mutation (The ReInspire Study)](https://trialight.com/data/trial/a-phase-2-study-of-mutant-selective-pi3k-inhibitor-rly-2608-cb48d7d4-b39e-48fc-b89b-e54745cb8b7c.md)
- Assessment of the Efficacy and Safety of Alpelisib (BYL719) in Pediatric and Adult Patients With Megalencephaly-CApillary Malformation Polymicrogyria Syndrome (MCAP)
- Effect of Low-Fat Compared to Low-Carbohydrate Diet in Subjects With Multifactorial Chylomicronemia
- National Evaluation of Patients With PIK3CA-Related Overgrowth Spectrum (PROS)

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