title: Squamous cell carcinoma originating from an epithelial scar in a horse.
abstract: A Quarter Horse stallion developed an abscess over the left gluteal region after an IM injection of antihistamine. The wound healed with considerable fibrous scarring and some persistent granulation tissue. The lesion was static for 2 years before the granulation tissue went through a 6-month period of progressive enlargement. At that time, histopathologic diagnosis of squamous cell carcinoma was made from excisional biopsy. Six months after diagnosis, the horse had lost body weight and the lesional diameter had further increased, so the horse was euthanatized.
authors.affiliation: Department of Large Animal Medicine and Surgery, Texas A&M University, College Station 77843-4475.
authors.forename: A N
authors.initials: AN
authors.lastname: Baird
authors.forename: P F
authors.initials: PF
authors.lastname: Frelier
mesh_terms: D000818:Animals; D002294:Carcinoma, Squamous Cell / Q000209:etiology / Q000662:veterinary*; D002921:Cicatrix / Q000150:complications / Q000662:veterinary*; D003937:Diagnosis, Differential; D006734:Horse Diseases / Q000209:etiology*; D006736:Horses; D007273:Injections, Intramuscular / Q000009:adverse effects / Q000662:veterinary; D008297:Male; D012878:Skin Neoplasms / Q000209:etiology / Q000662:veterinary*