pilomatrixoma
Findings
No curated finding names pilomatrixoma yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
Pilomatrixoma is a rare and benign hair cell-derived tumor occurring mostly in young adults (usually under the age of 20) and characterized as a 3-30 mm solitary, painless, firm, mobile, deep dermal or subcutaneous tumor, most commonly found in the head, neck or upper extremities. When superficial, the tumors tint the skin blue-red. Multiple pilomatrixomas are seen in myotonic dystrophy, Gardner syndrome, Rubinstein-Taybi syndrome, and Turner syndrome.
Definition from the Mondo Disease Ontology (MONDO:0007564), read 2026-09-29. CC BY 4.0.
- Inheritance
- Typified by somatic mosaicism
HPO, annotations 2026-09-02
Features
6 features
What the disease is reported to present with, and how often among people who have it — never how often a feature means the disease. HPO, annotations 2026-09-02.
- PilomatrixomaHPOHP:0030434
- Obligate (100% of cases)
- Neoplasm of head and neckHPOHP:0012288
- Very frequent (80% to 99% of cases)
- Subcutaneous noduleHPOHP:0001482
- Very frequent (80% to 99% of cases)
- Ectopic calcificationHPOHP:0010766
- Occasional (5% to 29% of cases)
- Anti-myeloperoxidase antibody positivityHPOHP:0033559
- Very rare (1% to 4% of cases)
- PruritusHPOHP:0000989
- Very rare (1% to 4% of cases)
Where it sits
Other names
5 names
Resolves to: pilomatrixoma
- Also called
- calcifying Epitherlioma of Malherbeepithelioma calcificans of Malherbepilomatricomapilomatricoma, somaticpilomatrixoma, benign