DO POSTVACCINAL SARCOMAS OCCUR IN AUSTRALIAN CATS

A soft tissue sarcoma occurred in the interscapular area of a cat, 1 e o 7 months after vaccination at that site. The vaccine contained inact ivated feline panleucopaenia virus combined with modified live feline herpesvirus and calicivirus. The tumour showed histological features o f both fibrosarcoma and malignant fibrous histiocytoma. The tumour was observed to evolve from the site of a presumed postvaccinal granuloma . Local recurrence 6 weeks post excision necessitated more: radical re section. Euthanasia was performed 2 years later when pleural effusion developed. The cause effusion was not determined There was ilo palpabl e evidence of local tumour regrowth at the rime of euthanasia. A causa l relationship between vaccination and sarcoma formation is considered based on the temporal association between the two events, the anatomi cal location of the tumour and histopathology consistent with postvacc inal sarcomas reported overseas. Six other vaccine sire fibrosarcomas, potentially vaccine associated using the above criteria, are summaris ed.