Managing epiglottal chondrosarcoma of a dog: A case report

Chondrosarcoma is a malignant tumor of cartilage; it may be primary, originating inside a bone (central) or from the periosteum (peripheral), or secondary, initiating through malignant change in osteochondromas [6,7]. Microscopically, the malignant c ells produce characteristic chondroid and fibrous matrix. Macroscopically, the chondrosarcoma develops on the bone surface, as large masses ranging in size from 2 to 20 cm in diameter with lobulated surfaces, firm or hard consistency, and relatively well bordered. Chondrosarcoma in dogs has a significantly higher incidence compared with osteosarcoma, where it frequently is located in flat bones [6,7]. The incidence of chondrosarcoma has been often reported in adult animals. The tumor has been particularly studied in dogs, where it account for about 10% of all bone sarcomas, pre-dominantly affecting large breed dogs especially the Boxer and German Shepherd breeds, with no sex preference. Chondrosarcomas have less tendency to metastasize compared with osteosarcomas. Metastasis of chondrosarcomas occurs via the hematogenous route mainly to the lung. In general, this occurs later in the course of the tumor development, but only in approximately 10% of the cases [6,7]. The only previous reported cases of chondrosarcoma of the larynx in veterinary literatures included a 10-year-old male Boxer and an 8-year-old male Doberman pinscher where the tumors were attached to the left arytenoid cartilage, but were not evaluated immunohistochemically [2,3]. There were no reports of chondrosarcoma of the epiglottis within veterinary literature. In this report, we present a low grade chondrosarcoma arising from the epiglottis of a dog, which was treated with surgical excision. In addition, gross, histologic, immunohistochemical, and histochemical findings of this tumor are discussed.