Unusual Cytologic Findings in a Dog With a Keratinizing Cyst and Cutaneous Asthenia

A 5-year-old spayed female golden retriever with a history of cutaneous asthenia (Ehlers-Danlos-like syndrome) was presented with a newly noted large hindlimb mass. Cytologic evaluation performed at the referring veterinarian was consistent with a keratinizing lesion. However, a second cytologic sample was obtained from the mass, aspirating from multiple aspects, and was concerning for a sarcoma. The mass was excised and submitted for histologic evaluation. The mass effect was diagnosed as a keratinizing cyst. Additionally, there were severe dermal collagen and elastin abnormalities with multifocal fibrosis and hemorrhage (consistent with cutaneous asthenia). To the best of the authors' knowledge, this is the first report of the cytologic findings in the skin of a canine with cutaneous asthenia.