Feline injection site sarcomas – the old and the new*

Feline injection site sarcomas – the old and the new

Feline injection site sarcomas are rapidly growing mesenchymal tumours that develop in sites where vaccines and other medications are administered. They are locally invasive tumours with a low-moderate metastatic rate. Tumour recurrence is very common and outcome improved when tumours are small at diagnosis and amenable to aggressive surgical excision. Multimodality therapy is often recommended however the precise role of radiation therapy and chemotherapy requires further investigation. Guidelines for feline vaccination have been developed in light of the potential for injection site sarcoma development at the site of vaccination.