Injection site sarcoma, cat

Injection site sarcoma, cat

Clinical photograph of a cat with an injection site sarcoma in a typical intrascapular location. These tumors develop in some cats (1–16 cases/10,000 vaccinations) due to chronic inflammation following administration of adjuvanted vaccines, inactivated rabies vaccines, long-acting corticosteroid injections, or other injections. The chronic inflammation causes neoplastic transformation of fibroblasts.

Courtesy of Dr. Alice Villalobos.