C. Brito; G.A.L. Veiga; A. Barbosa; K.S. D'Oliveira; J.F. Frignani; C.E.B. Domingues; C.P. Carramenha; S.M. Oliveira; C.F. Santos
Chondrosarcoma is a primary bone tumor of low incidence and represents less than 10% of the bone neoplasias that attacks dogs, is characterized as malignant, involving the proliferation of cells that produce cartilaginous matrix, however, this histological type presents less aggressive behavior when compared to osteosarcoma. Adult animals, with average age of 8 years old present more predilection and the Golden Retrievers presents 3 times more potential to develop this neoplasia than any other race. The present study reports a case of chondrosarcoma in young dog, considering that is a rare affection in animals less than 3 years old. A dog, male, German Shepherd, 11 months and 25 kg, was seen presenting lameness historical of left pelvic member. During the physical examination the animal presented restriction to the movement of abduction of the member and sensitivity in left hip joint. At the radiographic exam, it was detected loss of definition associated with the deformity of the left femoral head, due to radiotransparent areas in around as well as discrete adjacent irregular periosteal proliferation, besides morphologic alteration of ileum body and increase of the radiopacity in left acetabulum, being these radiological aspects compatible with aggressive bone injury. The radiographic evaluation of the thorax and abdominal ultrasonography, for metastasis research, did not show any alterations. The left colocephalectomy was realized aiming to reduce the discomfort of the patient, and the gotten material was sent for the histopathologic analysis. In immediate postoperative the animal presented significant improvement of the lameness. The histopathologic exam disclosed presence of infiltrative neoformation, with proliferation of mesenchymal ovoid cells with arrangement in cartilaginous lobes compatible with chondrosarcoma. The amputation of the member and the left hemipelvectomy had been indicated, however the proprietor opposed to the treatment for aesthetic reasons, choosing for a conservative treatment, with anti-inflammatory (carprofen) and analgesics (tramadol colidrate and dipyrone sodium). Studies demonstrate that the surgical excision with ample safety margin is a curative treatment for animals with chondrosarcoma. The present report of a chondrosarcoma case in young dog, out of predisposed year age, shows the importance of this differential diagnosis in patients with lameness, even young ones. Moreover it is important to observe that although the prognostic is good after the complete surgical excision, in this in case, the localization of the neoformation led to the necessity of a radical procedure, the hemipelvectomy, that not always is well accepted by the proprietors.