Vaccine-associated sarcoma is a rare but aggressive cancer in cats that develops at injection sites, requiring thoughtful vaccination protocols that balance disease prevention with risk minimization.
Vaccine-associated sarcoma creates a genuine welfare dilemma: vaccination prevents diseases that would cause suffering, but in rare cases triggers an aggressive cancer. The welfare framework balances the certain benefit to the population from disease prevention against the rare individual welfare harm from sarcoma. Injection site recommendations (distal limbs) address welfare by enabling more complete surgical resection if sarcoma develops. Non-adjuvanted vaccines reduce but do not eliminate risk. Individual risk-benefit analysis with your veterinarian, considering your cat's lifestyle and disease exposure, is the welfare-optimal approach.