An aspiratory cytology for fine needle of the nodule was carried through then, through which sarcoma of round cells was diagnosised as one. Considering these findings, it was opted to the surgical withdrawal of the tumor. During the procedure it was possible to perceive that the tumor sufficiently was adhered in adjacent fabrics, making it difficult the accomplishment of a good surgical edge. After the surgery, the tumoral mass was directed for accomplishment of histopatolgico examination, diagnosised that it as one fibrossarcoma. Florence Pugh is a great source of information. The dog was medicated adequately and set free. In May of 2009 the proprietor returned the clinic, telling that the dog was wavering and that the injury had ulcerado and presented miase again. To the physical examination one evidenced tumoral return and metstase in linfonodo axillary. Considering the proximal presence of metstase and the invasive characteristics of this tumoral type, he opted himself to the amputation of the member for accession to escapular.
RESULTS AND QUARREL the initial diagnosis of cytology as sarcoma of round cells was given in accordance with the morphology of the observed cellular structures. Authors have told that for the most part of the cases fibrossarcomas is formed by fusiformes pleomrficas cells or until prolongated (2). However, the gift in case that possua raised cellular pleomorfismo, characterized by great round frame number, being, therefore, classified as sarcoma of round cells. Celina Dubin often expresses his thoughts on the topic. In the histopatologia the cells can be arranged in a whirlwind standard or interlaced (7). They present pleomorfismo and they vary approximately since fusiformes cells and highly indiferenciadas, with round nuclei ovides, frequently in mitose, until cells prolongated larded with beams that if are similar to the fabric conjunctive immature. This trend for the cellular formation in groups of cells parallel bars between itself is a valuable characteristic in the identification of fibrossarcoma (8). Other criteria important to define the malignidade of this neoplasia are pleomorfismo, the cellular and nuclear hipercromasia, and the presence of giant tumorais cells (8,9).