Retrobulbar Fibrosarcoma in a Sheep

Abstract

This report describes a case of a retrobulbar fi brosarcoma in a 4-year-old female sheep. A big tumor was protruding from the orbit but not invading the surrounding tissue and was easily removed surgically. The grayish colored mass was 19x13x8 cm in size and hard. The surface of the tumor was irregular and ulcerated. Marked hemorrhage and necrotic areas were present across the whitish cut surface. Histopathologically, the mass was composed of spindle shaped, anaplastic pleomorphic cells. Masson's trichrome staining revealed a collagenous matrix in the tissue. Immunohistochemically, the mass was positive for vimentin and proliferating cell nuclear antigen but negative for smooth muscle actin, desmin, glial fi brilar acidic protein and S100 protein antibodies. According to histopathological and immunohistochemical fi ndings the tumor was diagnosed as fi brosarcoma. To the authors' knowledge, this is the fi rst report of ocular fi brosarcoma in a sheep.

Fibrosarcoma en ovinos de la zona altiplánica del Perú: reporte de casos

“…The metastatic capacity of any cancer, such as fibrosarcoma, is characteristic 23,21 , although some cases of this type of cancer do not necessarily cause metastasis 8 , but the cases of the present report did and especially the case 1 in which numerous metastatic nodules were observed in various organs including the lymph nodes of the abdominal cavity.…”

“…In both studied cases the neoplasms infiltrative ones into the adjacent tissues and particularly case 1 was very invasive and this morphological peculiarity corresponds to fibrosarcomas 21 . The tonality of the connective tissue cancer is usually whitish to greyish 8,18,21 and the consistency is generally firm 9,16 , these macroscopic characteristics were also observed in the specimens studied. However, in case 1, the nodules were found to be quite firm in consistency and when cutting them, strong resistance and a certain crackling sound, and a certain stony appearance were noted.…”

“…In order to interpret the macroscopic characteristics A mesenteric lymph node near this node was found to be very swollen, pale in color, resistant to cutting, with a similar appearance to the original node, and surrounded by a jelly-like substance (figure 3). reported tumors of this type located on the lips, gums, maxilla, and cornea in alpacas and llamas; some other cases of this malignant tumor may be located in deep soft tissues or near the bones 10 , in the genital organs such as the vulva or vagina 23 or in any other part of the body 8,9,16,20 .…”

“…Cancer of fibrous tissue, known as fibrosarcoma, according to the World Health Organization (WHO) is a highly malignant tumor disease of mesenchymal origin in which other types of histological structures such as bone and cartilage are absent 7 . Fibrosarcoma consists of a pathological proliferation of fibroblasts 8 , frequently affects dogs and cats, infrequently to equines, bovines, and pigs and rarely to other species 9 . This type of malignant neoplasm derives from connective tissue, it is characterized by fibrous tissue anaplasia 10 , it has no predilection for any sex but frequently to adults and it can develop anywhere on the animal`s body 9 .…”

Neoplastic mass involving the zygomatic arch in a sheep: clinical, sonographic, radiographic, pathological, and CT findings

“…Oral fibrosarcomas have previously been described in a goat,10 as well as in a survey of 9 out of 75 tumours from sheep grazing bracken fern 11. To the authors’ knowledge, there has been one report of a fibrosarcoma on the left side of the head, encompassing the occipital region12 and one of an ocular fibrosarcoma in a sheep 13…”