Cats: Vaccine-Related Sarcomas

This was a relatively short article and one topic, thankfully, that I have never experienced.  Since many of my cats do come from unknown backgrounds, I do suspect that some are at risk, but so far, so good. 

Recent Advances in the Treatment of Vaccine-Sarcomas, by Gregory K. Ogilvie, DVM
p 525-533 in Vol 31, No 3, Vet. Cl. of NA: Small Animal Practice, May 2001...

The article focuses on the diagnosis and treatment of the sarcoma and not on the fact that vaccines seem to cause sarcomas.  The latter is assumed by the article. The article doesn't mention, but from other sources the sarcomas are linked primarily to FeLV and rabies vaccines.

Physical exam -- The sarcoma appears as a lump or thickening either at the injection site or, interestingly, on the underside of the cat (migration of vaccine agent).  The lump can appear from days to years afterwards. This timing, days to years, is a bit scary since I do not know the vaccine history of many of my cats.

Evaluation -- The first step is a needle biopsy to confirm that it is a sarcoma.  The next step is xrays to determine if it has metastasized.  Enlarged lymph nodes may need to be biopsied.

Treatment of small tumors -- The recommendation is for a 2cm cuff around the tumor and 1 skin layer deeper.  2cm on both sides is HUGE!  The author mentions the inconclusiveness of both chemotherapy and radiation therapy, and from other sources, this does not seem to have changed significantly in recent years.

Treatment of large tumors -- The author recommends surgical reduction of the tumor followed by radiation treatment.

Metastatic sarcomas -- Chemotherapy seems to be the solution but at the time of writing there was no clear recommendations.

Patient Management -- The author stresses the need to give the client pain meds, anti-nausea meds, and appetite stimulants to help the cat.  Also, the client should be given written instructions and educational material because owners often are very upset when told their cat has cancer.

Prognosis -- For small, non-metastatic tumors, the prognosis is good.  Otherwise, the outcome is usually not good as the tumor recurs.  Who does the surgery and how extensive it was drastically influences the outcome:

"The median time of tumor control was 94 days.  Median tumor control for tumors treated with excision performed at a referral institution (274 days) was significantly longer than that for tumors excised by a referring veterinarian (66 days).  A radical first excision yielded significantly longer median tumor control (325 days) than did a marginal first excision (79 days)..... Few cats (13.8%) receiving only surgical treatment had long-term (>2 years) survival, suggesting that radiation and chemotherapy are highly indicated as adjunctive therapies."  And this is an interesting statement about radiation and chemotherapy given what the author said previously about the inconclusiveness.

These vaccine-related sarcomas are the reason the new vaccine protocols recommend vaccinating for rabies and FeLV in the legs or even tail -- those parts can be amputated to save the cat from the sarcoma.  To me this is very drastic and makes me ever so grateful that I don't have to vaccinate for rabies of FeLV.

Cats: Raw Food and FIP

Several cats helping clean the bowl after making the food

A friend asked me, as someone who has done extensive research on raw diets and who has fed raw for years, to comment on cats with FIP (feline infectious peritonitis) and raw diets.

One major arguments against feeding a FIP cat raw is with regards to the usefulness of raw diets.  No, there is no scientific research on the benefits of raw for FIP cats or any other cats because there are no scientific studies on raw vs. commercial.  There are the Pottenger's studies from the mid-1940s on raw vs. cooked diets and there are a lot of anecdotal evidence by long-term raw feeders, neither of which are rigorous scientifically.  But while there is no evidence to support it, there is, likewise, no evidence to not support it.  The concerns the veterinary community has against raw are not based on any scientific evidence to date. The lack of evidence can not and should not be construed to mean anything other than there is no research on the topic.

The second argument against raw is that no one has adequate training to judge the appropriateness of a raw recipe except a veterinary nutritionist.  I take offense at that.  I personally have the biochemistry, the statistics, the nutritional training, and, much more importantly, the experience of 25+ yrs of raw feeding to look at and analyze a recipe for the level of thiamine (1.4mg/1000 kcal ME).  It's not rocket science to take the food components and add up all the vitamins and minerals and then compare them to published requirements -- it's tedious, but this is how researchers do it.  (Many veterinary food researchers are not veterinary nutritionists, but nutritional researchers, some without a veterinary degree.)  There is in fact one

THE book on nutritional requirements for cats

company on line that will analyze raw recipes for all nutrients.  So, if someone does have a recipe, they can have it analyzed, or they can do it themselves, or they can ask those of us who have been feeding raw for years to look at it.

I would remind whoever that the general vet has 1 semester of small animal nutrition (cats, dogs, gerbils, and parakeets).  Vet nutritionists are better trained, but there are only a handful of board-certified ones in the US in private practice (ones with 2 yrs of extra training) -- many of those that are calling themselves nutritionists are not certified.  I had the opportunity to talk to one and was left very unimpressed by his knowledge on feline nutrition -- he was brilliant on canine nutrition, but dogs are not cats.

On a side note -- concerning the whole idea that a layman can't make cat food, I have fed my present recipe for ~15 yrs with no nutritional problems.  The recipe I use is borrowed from Michelle Bernard at Blakkatz Raw Recipes.  (Michelle used that recipe for a good 10 yrs before publishing it and raised champion American Shorthair cats on it.)  I have done nutritional screenings on my cats and there are no deficiencies or excesses.  I have analyzed this recipe and someone else had it analyzed by the company mentioned above -- it's fine.  This recipe also has been 'blessed' by my vet, 3 other vets of friends, and was deemed 'perfect' in terms of nutrition. While there are some whacko raw food recipes out there (ones that claim no supplements are required), there is at least one that is fine.

The third argument against raw is the issue of pathogens in the raw food.  Yes, this risk is there.  Given the number of recalls for canned and kibble foods, the risk is also there and of a much more serious nature since the pathogens found in commercial food seem to be of more virulent strains. But back to raw -- not only is the cat digestive system shorter so the bad 'bugs' have less time to colonize, the acid in the stomach is stronger so many of the pathogens that would sicken humans are destroyed by the cat's stomach acid.  I deal with medically fragile Persians from large public shelters and they all get transitioned to raw.  In the 25 yrs I've done raw, not one cat has had any food-borne illness from my raw.  Among my raw-feeding friends including owners of FIV and FeLV cats, not one of them have had problems either.  If you start with human-grade meats and handle it properly, the risk is minimal.

With respect specifically to pathogens, raw, and FIP, the argument is that the cat's immune system is already stressed so the pathogens are more problematic.  That sounds good, but the immune system in a FIP is over-reactive, not under-reactive.  Cats die from FIP not from secondary infections as they do with feline leukemia, but from the immune system destroying the cells of the body.

So, the bottomline is this -- if I had a cat with dry FIP, would I switch the cat to raw?  Probably yes.  I do not see any harm in a raw diet and I have seen major benefits from it in cats with IBD, diabetes, FeLV, and FIV.  If the cat was already showing symptoms, then maybe not if the cat was hesitant to eat the raw -- I would prefer to have the last weeks of the cat's life to be as free from stress as possible.  As for the wet FIP, no, I would just love the cat until it dies.