Objective— The purpose of this study was to determine the tumor-free interval and survival times of cats who had one (group 1) or more (group 2) surgeries, or surgery and radiation therapy (RTH) (group 3) for treatment of soft tissue fibrosarcomas (FSA).

Study Design— Retrospective study.

Animals or Sample Population— 45 client-owned cats.

Methods— Medical records of cats with soft tissue FSA were examined. Vaccination and feline leukemia virus (FeLV) status, age, sex, breed, tumor location, number of surgeries, completeness of excision, and histopathological grade were evaluated to correlate with tumor-free interval and survival periods.

Results— Overall median tumor-free interval and survival times were 10 and 11.5 (range, 1 to 40) months. Median tumor-free interval and survival times were more than 16 months each in group 1, more than 5 and 13 months in group 2, and 4.5 and 9 months in group 3. Age, sex, breed, vaccination or FeLV status, tumor location, or histopathological grade did not affect median tumor-free interval or survival times (P <.05). Cats with complete excisions had significantly longer median tumor-free interval (>16 versus 4 months) and survival time (>16 versus 9 months) than those with incomplete excisions (P=.008). Radiation therapy did not seem to extend tumor-free interval and survival times (P=.013). However, most group 3 cats had incomplete surgical excisions, resulting in recurrent or progressive disease.

Conclusions— Complete surgical excision of FSA in cats is possible and can be curative.

Clinical Relevance— Aggressive surgical excision with wide margins appears to contribute to extended tumor-free interval and survival times in cats with soft tissue FSA. Controlled prospective studies are needed to determine the efficacy of RTH in treatment.