Outcome following removal of canine spindle cell tumours in first opinion practice: 104 cases.

OBJECTIVES: To define the outcome of a cohort of canine patients with a histological diagnosis of spindle cell tumour of soft tissue managed solely by surgery in first opinion practice.

METHODS: Clinical details of 104 spindle cell sarcomas submitted to Finn Pathologists during the year 2000 were reviewed. Questionnaires were sent to the submitting veterinarians, requesting details about the tumour, surgery performed and ultimate outcome of the patient.

RESULTS: The method of surgical resection was described as marginal in 45 dogs (44.2 per cent). Excision margins of 3 cm or more were described in less than 10 per cent of cases. Tumours recurred locally in 29 dogs (27.9 per cent). Eighteen dogs (21.7 per cent) died of tumour-related causes. Most deaths were unrelated to sarcoma (50 dogs, 60.2 per cent) or unknown (15 dogs, 18 per cent). The median survival time was 1013 days. Tumour size, location or degree of surgical resection were not significantly related to survival or tumour recurrence. A palpable assessment of tumour invasion into underlying tissues was significantly associated with decreased disease-free interval (P<0.0001) and survival time (P = 0.0070).

CLINICAL SIGNIFICANCE: The results of this retrospective study indicate that many spindle cell tumours managed in first opinion practice exhibit a low-grade biological behaviour and may respond well to more conservative surgery than current recommendations advise.