Vaccine-Associated Sarcoma

OVERVIEW
Cats—vaccination may induce development of sarcoma (primarily fibrosarcoma) at the injection site, primarily in the muscle, skin, and subcutaneous tissues; malignant fibrous histiocytoma, osteosarcoma, rhabdomyosarcoma, and chondrosarcoma also associated
FeLV and rabies vaccines—most common
Interval from vaccination to tumor development—may be as short as several months
Metastasis common
Fibrosarcoma—prevalence in cats unknown; estimated at 20/100,000 cats