Fibrosarcoma in the saddle area in a dressage horse

An eight-year-old Hanoverian gelding was presented with a progressively growing mass in the left cranial region of the saddle area and a history of riding problems. A firm, poorly circumscribed, non-painful tissue was palpable. Diagnostic imaging revealed a calcified mass in the depth of the swelling. This calcified mass was excised out of the musculus longissimus thoracis under general anesthesia. Post surgery the horse developed a non-healing and intermittendly profusely bleeding wound. During the treatment of this non-healing wound tissue samples were sent to a laboratory for histopathological and immunohistochemical analysis. The analysis confirmed a fibrosarcoma. The horse was euthanized because of a very poor prognosis.