We use the every three year rabies vaccines but it is possible to make a very good case for using PureVax (tm, Merial) rabies vaccine, which is thought to be less likely to cause cancer
at vaccine sites.
You're likely thinking of Feline Vaccine Associated Sarcoma, an aggressive cancer sometimes occurring at
vaccine sites in cats.
However, dogs with GVIID usually have a demonstrable focal lesion at the
subcutaneous vaccine site compatible with the lesions seen with localized post rabies vaccination panniculitis.
It is highly suspected that adjuvanted feline vaccines do carry an increased risk for inducing
feline vaccine site sarcomas, so while there is not a complete consensus in the veterinary community, many studies in peer reviewed scientific journals and many veterinary specialists recommend using only adjuvant free vaccines in felines to reduce these risks.
It can take as short a time as two months and as long as ten years to develop
a vaccine site tumor but most appear within 4 years of the offending injection..
For 24 hours after a vaccine is given, it is common for pets to experience mild pain / swelling at
the vaccine site, mild fever, decreased appetite or activity, and sneezing / mild cough (for Bordetella vaccine).
In these cats,
the vaccine site is chronically inflamed post-vaccine, which can develop into a tumor.
Rarely, however, the swelling may progress to a sarcoma, so it's important that you contact your veterinarian if you notice a swelling at
the vaccine site.
Medication reactions, including vaccine reactions, are generally limited to lethargy and mild itchiness / tenderness at
the vaccine site for 24 hours.
Most of
these vaccine site cancers have been found in cats.
Again,
these vaccine site cancers are rare to uncommon in cats, and even rarer in dogs.
Although the cancer is rare, it's believed to be due to an inflammation at
the vaccine site.
Exactly why remains a mystery, but cats who still have a lump at
the vaccine site a month after an injection should be examined by a veterinarian.