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    My 8 year old cat died of bladder cancer
    ksmith06 posted:
    My 8 year old cat started having UTI symptoms in February of this year. On March 12, 2013 he was completely blocked and could not longer be catheterized so our Vet opened him up to see if she could work on his bladder that way. What she found was black masses of cancer lining his bladder and underneath it. My question is, could the 23 year rabies vaccine that he was given 3 years ago have caused this? She informed us that this was rare in cats and could not believe what she saw when she opened him up. He was in excellent health and within a month after having the UTI symptoms, he was dead. I was given a paper after he was vaccinated that said the 3 year rabies shot could cause cancer, and had I known that beforehand, I would have never allowed it to be given.
    srstephanie responded:
    Hi ksmith06,

    My condolences on the loss of your kitty. Many of us have gone through it and know the pain and grief.

    The cancer caused by vaccinations (or other injections) is usually a fibrosarcoma and is seen at the site of the vaccination. So, it is unlikely that bladder cancer is a result of a vaccination, unless the vaccination was given near the bladder, which I doubt happened.

    A little on the Vaccine Associated Sarcomas (VAS) which are also called Feline Injection Site Sarcomas (FISS).

    The problem is not the vaccine itself but rather chronic inflammation that is caused by the vaccination. Some cats have a genetic predisposition which causes the immune system to react to the inflammation in a way that results in a mutation to the P53 gene. The P53 gene is a "tumor suppressor" gene. When it mutates, it no longer suppresses cell reproduction and cancer develops. So, two things are needed for a VAS:

    1) Inflammation (particularly long term chronic inflammation)
    2) genetic predisposition (which results in a mutation of the P53 gene that allows tumor growth)

    A fibrosarcoma (cancer) may occur as a result of any inflammation, not just that caused by vaccinations. Thus, the experts are now starting to prefer to use the term Feline Injection Site Sarcoma (FISS). It has been seen after injections of long acting steroids, antibiotics, insulin and even just subcutaneous fluids. Some cats are so sensitive that any inflammation can cause it ... even things other than injection. It has been seen as a result of inflammation caused by eye trauma, or sutures, or even when a vet accidentally left a piece of gauze in at a surgery.

    But vaccines, particularly the Rabies and Feline Leukemia vaccines are most implicated because most of them are Killed Virus (KV, also called "inactivated") vaccines. That means that the vaccine is made by taking either rabies or FeLV and killing the virus and injecting it. But the immune system is smart enough to know that the virus is dead and not a threat, so it doesn't respond. So, they have to add a chemical to the vaccine called an adjuvant, often (but not always) aluminum. The whole purpose of the adjuvant is to create inflammation at the vaccination site and hold the vaccine there. The inflammation is like holding a sign up to the immune system and telling it to come here and respond. There have been studies to show that the inflammation caused by KV vaccines lasts for months and likely years. A fibrosarcoma has developed as long as 9 to 11 years after the last vaccination. But the cancer occurs under the skin at the vaccination site.

    It is true that it is a rare cancer ... estimated at between 1 in 1,000 and 1 in 10,000 vaccinations. But that still translates into thousands of cats each year in the US. We don't know what cats have the genetic predisposition, so it is wise to avoid using adjuvanted KV vaccines.

    There is one alternative type of vaccine for both rabies and FeLV vaccines that are not adjuvanted. They are the recombinant vaccines that are made by a company called Merial in their Purevax line. They are made by taking just a small piece of DNA from rabies or FeLV and inserting it in a carrier virus, i.e. the canarypox, which is a bird virus that is not able to replicate in mammals. They are very good vaccines and produce very little inflammation that is gone within a couple days. The only draw back is the rRabies is licensed as a 1-yr vaccine and has to be boostered annually.

    For the other "core" vaccines (Panleukopenia, Herpes, Calici) it is recommended that a Modified Live Virus vaccine be used. They give better protection and do not have any adjuvant ... and very little inflammation.

    All that said, I don't think a vaccination would cause bladder cancer. The cancer caused by vaccines (and other inflammation) is usually a lump under the skin at the site of the vaccination.

    Hope that helps.
    Stephanie in Montreal
    Drew Weigner, DVM, ABVP responded:
    While vaccines can cause cancer in rare instances, it's not this type of cancer, so it's unlikely his Rabies vaccination had anything to do with it. Unfortunately, bladder cancer in cats is very aggressive and, as you now know, has a poor prognosis. We're so sorry for your loss.

    Drew Weigner, DVM, ABVP
    The Cat Doctor
    Board Certified in Feline Practice
    ksmith06 replied to srstephanie's response:
    Thank you for taking the time to reply.
    ksmith06 replied to Drew Weigner, DVM, ABVP's response:
    Thank you replying. It is so hard to watch a seemingly healthy cat be put down in the course of 2 days. A 3 year rabies shot was just something we were trying to pin it to. Our 7 year old female has had the shot also and is in what seems to be in great health. I am just so overcome at times at how quickly he was taken from us. We were willing to spend whatever it took to make him better. Thanks again.
    lakota3 responded:
    Hi, I just had to put my cat down because of bladder cancer. He was always such a healthy cat. I am concerned that environmental factors may have caused this disease. So sorry to hear about your loss.

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