Lab Anim Res.  2010 Mar;26(1):117-120. 10.5625/lar.2010.26.1.117.

Pilomatrixoma in a Maltese Dog

• Chung JY
• Do SH
• Park SJ
• Jeong KS

• KMID: 1458949
• DOI: http://doi.org/10.5625/lar.2010.26.1.117

Abstract

A 12-year-old female Maltese dog brought to a local veterinary clinic with two nodules in the subcutis of left shoulder. The nodules were grown gradually from 2 years ago. The nodules were removed surgically under anesthesia and examined histopathologically. They were 15x26 mm in diameter (oval form) and 12x15 mm in diameter (round form), respectively. Histopathologically, the lesions consisted of multilayered basaloid cells in the peripheral of the mass and ghost cells in the central region. Typical findings of these two nodules were gradually keratinized basaloid cell toward central area result in forming anuclear ghost cells. These microscopic features of cutaneous nodules were diagnosed as pilomatrixoma and the identified findings were similar to fully developed stage of human pilomatrixoma. This report may assist in the categorizing of canine pilomatrixoma using histopathological features.

Keyword

Pilomatrixoma; pilomatricoma; skin tumor; dog

MeSH Terms

Anesthesia
Animals
Child
Dogs
Female
Humans
Keratins
Pilomatrixoma
Shoulder
Keratins

Figure

• 

  Figure 1. A: Dome-shaped surface with mild pigmentation and alopecia. B: Creamy-white to yellowish color, firm, well-lobulated and solitary appearance on the cut sections.

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  Figure 2. A: The subcutaneous cyst showed enlarged lumen and irregularly shaped and densely packed basaloid cells (1) in the rim. Gradually degenerated cells, ghost cells (2), were in central lesion. B: In the larger magnification of A, basophilic basaloid cells (1) showed nuclear mitosis (arrow) in the junction of degenerated cells. Ghost cell (shadow cells) (2) were disappeared nuclei and poorly stained but maintaining their outline. H&E stain. Scale bar=150 µm.

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  Figure 3. Multifocal mineralization was observed in the central region of the cyst. H&E stain. Scale bar=300 µm.

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