Feline vaccinal sarcomas (Proceedings)

The recognition of the development of potentially malignant tumors arising from injection sites became one of the most significant events in veterinary medicine in the 1980's and beyond. So significant, in fact, that it caused an entire profession to re-evaluate the way preventative medicine should be considered from a medical and an economic perspective.

This presentation discusses the orienting of a veterinary practice towards enhancing the feline component of practice: how to position a practice so that feline clients understand that their veterinarian manages a business sensitive to the needs of cats and those clients that own them. The demographics and psychographics of the feline client will be discussed in the process of discussing the business of cats.

Historically, this presentation reviews the historical epidemiology leading up to the recognition of the phenomenon of FVAS . The pathogenesis of FVAS will also be discussed in detail. Chronic inflammatory response in the subcutis of the cat has been documented as one of the, if not the, most important triggering mechanisms in the development of these sarcomas. Chronic inflammation alters the genetic control of cell death with the resulting formation of abnormal clones of cells being produced. This begins the cycle of the development of FVAS. Adjuvants (chemicals added to vaccines to increase the body's response to the antigen in the vaccine) can be the principle cause of the production of this chronic inflammatory response in the subcutaneous tissue of cats.

Multimodal (surgery combined with radiotherapy and/or chemotherapy) therapeutic strategies stand the best chance for a better therapeutic outcome for FVAS. However, early recognition of these tumors and the early strategy the veterinarian employs for diagnosis/removal can be critical to case outcome. But, unless aggressive diagnostic and therapeutic plans are employed, the prognosis is generally not good.

Prevention is definitely the best medicine in this disease. Recommendations by the Feline Vaccinal Task Force and the American Association of Feline Practitioners state that vaccines should produces as little inflammation as possible to prevent these tumors from occurring.