Pilomatricoma (Pilomatrixoma)

Key Points
Benign, uncommon skin lesion which typically affects the head and/or neck, but may occur anywhere
Like most noncancerous tumors, cause is unknown, but may be due to genetic mutations in hair cells
Typically consists of a solitary purple or skin-colored lesion, which may feel hard and are angular in shape

Pilomatricoma is a benign, uncommon skin condition which typically affects the head and/or neck, but may occur on any part of the body with hair. The condition typically consists of a solitary purple or skin-colored lesion, which may feel hard or bony due to calcification and be angular in shape. Lesions may uncommonly grow large in size (up to several centimeters). In rare cases, multiple lesions may occur in relation to myotonic dystrophy, a very rare neurological disorder.

The exact cause of pilomatricoma is unknown, but it may be related to a gene mutation in the hair cells. The condition typically appears in very young children, but may also develop in adults.

Differential Diagnosis (Other conditions with similar appearance)
Epidermal inclusion Cyst
Pilar Cyst
Lipoma

Diagnosis
Key Points
Diagnosis based on examination of lesions by ultrasound or xray
Skin biopsy may be performed to confirm diagnosis and rule out other conditions
In cases with joint pain, health care professionals may order x-rays

Pilomatricoma is typically diagnosed based on the examination of lesions by ultrasound or xray. A biopsy of the affected area may be performed to confirm the diagnosis and to rule out similar appearing conditions.

Treatment
Condition does not resolve spontaneously
Treatment typically consists of removal of lesions

Pilomatricoma does not resolve spontaneously, and treatment typically consists of the removal of lesions via surgical excision. If lesions are not completely removed, recurrence is likely.