Shih-tzu Case

Species: Canine
Breed: Shih-tzu
Age: 2yrs
Gender: Male Neutered


Firm, solid, freely movable, confined to site area, focal, from the right lateral chin as indicated in the diagram.

Click here for the IDEXX Pathology Report on this case.

Microscopic Description:

The sample of skin contains a well demarcated, nonencapsulated proliferation of small basaloid cells forming small nests, ribbons, and cords. There is a supportive collagenous stroma. Individual cells have oval nuclei, stippled chromatin, small single to indistinct nucleoli and small amount of eosinophilic cytoplasm. There is minimal nuclear pleomorphism and mitotic figures average <1 per 10 high power field.

Microscopic Interpretation:

Interpretation:   Haired skin: Trichoblastoma

Excision:  Extends to deep margin


Trichoblastoma (previously basal cell tumor) is a benign neoplasm of follicular germ cell origin in dogs and cats. Trichoblastomas occur most frequently on the head and neck. With complete excision, local recurrence is not anticipated.

Image Notes:

  1. Low magnification view of the lesion, demonstrating a well demarcated, non encapsulated, multilobulated, dermal mass.
  2. Higher magnification view of the lesion, demonstrating cords of basal epithelial cells supported and subdivided by dense collagenous stroma.

Leave a Reply