Hi Karin,
I am sorry to hear that your dog was diagnosed with mast cell tumor. I will allow veterinarians who are oncology specialists to address the specific tumor type, but I can help you with your questions regarding cancer and nutrition.
Feeding a food that is formulated to include increased fat and protein and reduced carbohydrate is recommended. If you have the food's recipe and caloric distribution, a general guideline is for fat to supply 50 to 60 percent of calories, protein to supply 30 to 40 percent of calories, and carbohydrate to supply the remainder (10 to 20 percent). This is beneficial because it shifts energy metabolism away from carbohydrates (which tumor cells prefer) and towards fat/protein (which tumor cells cannot use as efficiently). Another benefit is that this profile generally is more palatable (and more energy dense), which is helpful for pets who have reduced appetite or who begin to experience cancer cachexia (which is probably not yet a concern for your Oreo).
The type of fat is also important. The anti-inflammatory effects of omega-3 fatty acids on multiple systems of the body suggest a role in treating cancer patients. There is an increasing body of evidence showing that omega-3 fatty acids, particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), limit tumor growth. A certain level of linoleic acid (an omega-6 fatty acid) is required, and it is almost impossible (and not advisable!) to formulate a food that has no omega-6 fatty acids. Rather, we want to increase long-chain omega-3 fatty acids (from fish oils) to reduce the ratio of omega-6 to omega-3 fatty acids in the food. So, rather than add a supplement to a food, you are better served to feed a food that already has increased omega-3 fatty acids (specifically, EPA and DHA), and has a ratio of n-6 to n-3 of between 10:1 and 5:1. (I should mention here that the evidence of benefit in dogs has been in dogs with lymphoma, and to my knowledge, no studies of dogs with mast cell tumor and omega-3 fatty acids have yet been reported).
Last (sorry for the length of this): There is not consensus regarding benefits of antioxidant nutrients for dog and cat cancer patients, and increasing these nutrients may be contraindicated for pets who are receiving radiation or chemotherapy because antioxidant function may interfere with these treatments. Increasing antioxidants too much can also interfere with the anti-inflammatory effects of EPA. Conversely, it is theorized that providing supplemental antioxidants may reduce clinical signs of oxidative stress associated with some types of cancers (lymphoma) and may also be helpful in reducing the adverse effects of chemotherapy and radiation therapy. There is in some evidence to support this, but not all studies have shown a benefit and clinical trials, especially with dog and cat cancer patients, have not been reported. Although increasing vitamin E is commonly recommended for cancer patients, there is no evidence suggesting it is beneficial; same with vitamin C. (I have no idea what "Therapeutic M" is and would not recommend adding something that is not identified as an actual nutrient, nor has been studied, to any dog's food. If you do want to add some vitamin E, make sure that you add less than 200 to 400 IU per day, as there is evidence that increasing E too high has a negative effect upon immune health.
To summarize - evidence to date supports feeding increased fat/protein, reduced carb food; with increased omega-3 fatty acids and adjusted ratio, and if desired, moderately increased vitamin E, and beta-carotene (vitamin A precursor) to aid in oxidative stress.
Good luck with Oreo - I hope that she does well and that you see no recurrence of the mast cell tumor.
Best,
Linda Case
AutumnGold Consulting
Author: "Canine and Feline Nutrition: A Resource for Companion Animal Professionals"
Hello
In my experience with grade 2 mast cell tumors, metastasis is rare and generally once they are removed, they may reoccur locally but do not become invasive. I agree with Dr. Case's comments.
Although published research is still lacking we have had excellent results with our patients using the anti-cancer diet along with a natural vitamin supplement called Paaws.
Our studies have shown that the nutrients in Paaws, which are a patented combination of antioxidants, vitamins, minerals, omega-3 fatty acids, digestive enzymes, herbs and colostrum act synergistically to boost internal immunity and promote wellness which helps to combat these age related conditions and promote quality of life.
Thank you,
Dr. Carol Osborne, DVM