Fibrosarcoma

Fibrosarcoma is a malignant tumor arising from fibroblasts, the cells of connective tissue. It is a slow-growing tumor that rarely metastasizes but is markedly locally invasive. When located on the eyelids, it frequently involves the globe and orbit as well. The lesion appears as a firm, poorly mobile subcutaneous swelling that may have an ulcerated surface. It occurs more frequently in middle-aged large-breed dogs, including Golden Retrievers, Doberman Pinschers, and Rottweilers. It is a common tumor in older cats but may occasionally occur in younger cats, and the source notes a suspected association with mutation related to feline leukemia virus.

Treatment

Fine-needle aspiration and examination of the aspirate may provide a preliminary diagnosis. Definitive diagnosis is made by histopathologic examination after surgical removal, which also determines the degree of malignancy. Greater mitotic activity is associated with greater malignancy. Radiography, CT, and MRI are used to assess invasiveness and detect metastases. Because of the tendency to recur, treatment is aggressive and includes removal of the tumor and surrounding tissue, together with radiotherapy and/or chemotherapy.

Invasive fibrosarcoma of the lower eyelid in a dog. A suture is used to mark the nasolacrimal system before surgery to avoid damage and facilitate reconstruction.

Adapted from the Atlas of Ocular Diseases in Dogs and Cats by Dr. Siniša D. Grozdanić and colleagues. © Animal Eye Consultants of Iowa. The text and clinical images on this page are original content from the authors' own clinical practice and research, and may not be reproduced, distributed, or repurposed without permission.

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