Desmoplastic Tricholemmoma in a Dog

The document described a rare case of desmoplastic tricholemmoma in a 10-year-old mixed breed dog, characterized by a 0.8 cm facial mass. The tumor, originating from the outer root sheath of hair follicles, was diagnosed through histopathological and immunohistochemical analysis, showing cells arranged in lobules, nests, and cords within a desmoplastic stroma, and positive for cytokeratin 15, cytokeratin 19, and CD34. This case underscored the importance of considering desmoplastic tricholemmoma in the differential diagnosis of canine skin tumors and contributed valuable insights to the limited veterinary literature on this condition.