Mast Cell Tumors in Dogs: some advances in conventional care
Dr. Demian Dressler is internationally recognized as “the dog cancer vet” because of his innovations in the field of dog cancer management, and the popularity of his blog here at Dog Cancer Blog. The owner of South Shore Veterinary Care, a full-service veterinary hospital in Maui, Hawaii, Dr. Dressler studied Animal Physiology and received a Bachelor of Science degree from the University of California at Davis before earning his Doctorate in Veterinary Medicine from Cornell University. After practicing at Killewald Animal Hospital in Amherst, New York, he returned to his home state, Hawaii, to practice at the East Honolulu Pet Hospital before heading home to Maui to open his own hospital. Dr. Dressler consults both dog lovers and veterinary professionals, and is sought after as a speaker on topics ranging from the links between lifestyle choices and disease, nutrition and cancer, and animal ethics. His television appearances include “Ask the Vet” segments on local news programs. He is the author of The Dog Cancer Survival Guide: Full Spectrum Treatments to Optimize Your Dog’s Life Quality and Longevity. He is a member of the American Veterinary Medical Association, the Hawaii Veterinary Medical Association, the American Association of Avian Veterinarians, the National Animal Supplement Council and CORE (Comparative Orthopedic Research Evaluation). He is also an advisory board member for Pacific Primate Sanctuary.
Updated: May 6th, 2019
Hi! I have been getting feedback about mast cell tumors and I would like to get some info out there. I will focus on some conventional medicine advances for the time being that should be thoroughly checked into by dog lovers interested in mast cell tumors. These are not general cancer recommendations, rather just a window to full spectrum care, which is a phrase I coined to describe evidence-based selection of cancer fighting weapons from any source. I will focus on Western (allopathic) viewpoints today.
First, the traditional treatment is surgery…get ’em out. I wrote about pre-treatment with Benadryl before surgery, in a previous post, so remind your vet. Have any mass aspirated (needle biopsy) before surgery to diagnose most mast cell tumors so your vet surgeon has a general diagnosis before surgery.
Chemo consists of drugs like prednisolone, vinblastine, and others traditionally. Chemo in dogs is tolerated better than in humans as lower doses are used for cancer. The word “chemo” has a bad ring to it, but this is a prejudice developed from human medicine. Dogs generally handle it better, on the average, although everyone is different.
Note: if you have a Collie or related breed, make sure your vet tests for a MDR-1 gene mutation common in these herding dogs. This genetic issue may increase chances of side effects not only from vinblastine (above), but also vincristine and doxorubicin. Doses of these drugs shoud be lowered significantly if your dog is positive on this test. For more information, see the post on 8/30/08.
Predisolone or prednisone (“pred”, ) are cheap, common, side effects are most often not too bad, and they are tablets so you can change the dose easily depending on your dog’s responses. Vinblastine is a stronger chemo vinca alkaloid chemo agent, more potent than pred, which requires the dog to be in the hospital for injections. Some oncologists like cyclophosphamide and L-asparaginase (you’ll get different opinions and preferences from different oncologists). These are all used for mast cell tumors.
Some stats for Grade 3 mast cell tumors treated with surgery, pred, and vinblastine: At 1 year after surgery, 57% of dogs were still alive, and at 2 years 45% were still alive. Average remission times are about 10 weeks to 5 months with surgery, prednisolone, and vinblastine. Remember, every dog is different, however.
Radiation is used for mast cell tumors that are difficult to remove completely, or any grade 3. This can be high voltage radiation, or brachytherapy, which involves the use of radioactive implants within the tumor site. Yes, a little weird, involved, and costly, but long remissions in the literature.
For more helpful information and tools on Mast Cell Tumors, get a copy of the Dog Cancer Survival Guide
Many are not into invasive care, so take a look below:
One that should be considered for a less intensive protocol is Lomustine or CCNU. This drug has gotten a lot of attention in the last couple of years for good reason. It is a pill,and can be given every 3 weeks. Pretty easy and non-invasive, unlike most chemo protocols, and is a single agent so it is simple. About 40% of dogs with mast cell tumors respond to CCNU all by itself, which is pretty darn good.
Cimetidine should be used in dogs with mast cell tumors, especially those with decreases in appetite or vomiting. This is an antacid which kills two birds with one stone. Mast cell tumors cause excessive acid production in the stomach when they get bad, which cimetidine counters. Additionally, cimetidine has some good anticancer effects that have nothing to do with acid stomach. Finally, it is cheap and easy to get.
Ask your vet about intralesional triamcinolone. They may have not used it before, so do not be surprised, but they can access the info easily (1 mg per cm q 2-3 weeks SQ). It is an simple injection of a form of cortisone that most vets will have sitting on their shelves. It is not very expensive, and very common. Every 2-3 weeks, your vet can inject the mast cell tumor, or infuse the area where the mast cell tumor was removed, with a small dose of this drug. The direct contact of the triamcinolone with any mast cells left in the body will blast them pretty good.
A new drug called SU 111654 (great name eh?) is being worked on at Michegan State University. Looks promising. There is also a technique out there consisting of injecting the mast cell tumor sites with deionized water. Cheap as dirt, but mixed reviews.
This post is just a piece of full spectrum cancer care for mast cell tumors folks. There is a lot more, but I’ll let you sink your teeth into this…
Best to all,
Dr Dressler
Dr. Demian Dressler is internationally recognized as “the dog cancer vet” because of his innovations in the field of dog cancer management, and the popularity of his blog here at Dog Cancer Blog. The owner of South Shore Veterinary Care, a full-service veterinary hospital in Maui, Hawaii, Dr. Dressler studied Animal Physiology and received a Bachelor of Science degree from the University of California at Davis before earning his Doctorate in Veterinary Medicine from Cornell University. After practicing at Killewald Animal Hospital in Amherst, New York, he returned to his home state, Hawaii, to practice at the East Honolulu Pet Hospital before heading home to Maui to open his own hospital. Dr. Dressler consults both dog lovers and veterinary professionals, and is sought after as a speaker on topics ranging from the links between lifestyle choices and disease, nutrition and cancer, and animal ethics. His television appearances include “Ask the Vet” segments on local news programs. He is the author of The Dog Cancer Survival Guide: Full Spectrum Treatments to Optimize Your Dog’s Life Quality and Longevity. He is a member of the American Veterinary Medical Association, the Hawaii Veterinary Medical Association, the American Association of Avian Veterinarians, the National Animal Supplement Council and CORE (Comparative Orthopedic Research Evaluation). He is also an advisory board member for Pacific Primate Sanctuary.
Dear Dr. Dressler,
Thank you for the info. Took Cassie to the vet yesterday for a chemo treatment but her white blood cell counts were too low to give. Oncologist said that this was typical and not to worry. She also said that Cassies’ tumor is almost gone. How could this be. I am so happy. Ordered K9 Immunity and received it yesterday and have started Cassie on it. The other things that showed up on her X rays were negative so this was very good news. I hope and pray that all will be well. I read your post on Artmisinin and am thinking maybe I should get some of this. Can you get it at a Health Food Store. I don’t know where to start to look for it. Is there another name for it perhaps.
Joanne
Dear Dr. Dressler,
Cassie had her first chemo done today,also fine needle aspirate of the dot on her spleen. The protocol that this oncologist is using is as follows: Vinblastine and lomustine with prednisone pill. Is this a good protocol. She pooh pooh the luteolin and did not even want to hear about it. She told me that she is the oncologist and that I must follow what she says. Unfortunately this Animal Hospital (tops in our city of Ottawa) is the only one that does chemo. So, I guess that I am stuck with her protocol. The above would go on for nine weeks. Boy is this chemo expensive. Thank goodness I have pet insurance!!! It only covers $2,000 but that is better than nothing. I have been giving it some thought and I am considering ordering the K9 Immunity, even though our dollar is only worth 79 cents. Do you think that it would really help my dog. As I said before I don’t get good vibes off of the people I have seen so far so I am left in the lurch, sort of speak, and have to trust them whether I like it or not. Your comments or any help you can give would be most helpful. Once again I would like to take this opportunity to thank you as I know you are very busy.
Regards,
Joanne
That is too bad about the oncologist. You might want to read the post about prejudice in viewpoints, which, of course, is just another viewpoint (mine)! As far as chemo goes, yes, it is good. And in all honesty oncologists have more experience than I delivering chemo protocols as that is what they spend most of their time doing. I cannot say whether the K-9 immunity will for sure help your dog, only that some dogs benefit from beta glucans…which is the best anyone can say.
D
Dear Dr. Dressler,
Thank you so much for your reply and suggestions. On Tuesday we will be taking our Lucy to see the Oncologist to discuss her case and possible treatment, also on Tuesday Lucy will have an ultrasound done to check for any possible masses internally. On your suggestion we will stop the raw diet and have made a list to take with us to the appointment to discuss adding the supplements you have told us about. We are also currently giving Lucy the K9 Immunity and K9 Trans Factor supplements along with fish oil. Do you think that the Krill oil would be a better oil to use? Thank you again for your help.. Shirley
I like krill oil for the reasons stated in the blog post (my personal opinion). You might be interested in the e-book coming, my dog cancer survival guide, should be out within a few weeks, which goes into a lot of detail about the omega 3 fatty acids..
Best,
D
Dear Dr. Dressler,
My 3 year old golden lab recently (October) had a mast cell tumour removed from his chest. It was classified as grade 2, they believe it was removed with clean margins and liver and spleen biopsies (and ultrasound) indicated that the tumour did not appear to have metastasized (sp?) at this point.
He has been particularly itchey dog all of his life (chews his feet ALOT), and this doesn’t seem to have changed. In addition his scar from his surgery seems to change colour (some days seem very red), something that we had noticed with his actual tumour, is this something we should be worrying about?
At this point in time we have been advised that additional treatment does not seem necessary and that we should just check him over regularly for lumps etc.. does this seem reasonable advice?
Thank you so much for your time and help
Natalie, sorry to hear about this.
Sounds like you may have an allergic dog, which has a theoretical link with mast cell tumors. Talk to your vet about treatment for itch, also whether benadryl and cimetidine might be worthwhile. Find out also the mitotic index of the tumor (how many cells were dividing per high power field, a measure of how aggressive it is). If 5 or less, this is more aggressive (a fast moving cancer) and you would, in my opinion, consider more treatment. If over 5, median survival is 70 months, generally less aggressive.
D
Dear Dr. Dressler,
Thank you so much for your suggestions. I have now been informed at our vet appointment this morning that the tumor is a Grade II. The surgeon whom my vet called said that it would be impossible to operate on. He also suggested amputation. I also found out that the only place that has radiation therapy near me is in Guelph, Ontario which is about a 10 hour drive. I would have to leave the dog there. As she is so attached to us so this is not an option. I have an appointment with an Oncologist tomorrow to see what she suggests. I feel so alone in this because my vet is not a surgeon, nor is she really versed on mast cell tumors. The surgeon said that he did not feel that the other dots on the x rays were harmful but I want to have a needle aspirate done on the one near the spleen as these could be more mast cell tumors (he said doubtful). You would think that in a place like Canada we would be more cognisant of what is out there to treat this horrible disease and also have a radiation therapy clinic nearby. I have read every post on your site and have sat here for hours on my computer searching for answers. As far as her diet goes I have found some food (hard)called Holistic Blend, has lamb meat,millet,brown rice,amaranth,barley,salmon,flax seed and alfalfa, does this sound OK? slso will start her ob krill capsules and other things and will start her on this. At this point I feel everything is just an exercise is futility. I will not give up no matter what though. It does not look like the prognoses for my dear Cassie is very good does it. I will certainly mention the luteolin. I mentioned it to my vet but she didn’t seem interested. Is there anything else that you can suggest.
Thank you again so very much,
Joanne
I would really try to push your vet to consider intralesional triamcinolone. Do not be afraid to get a second opinion!
D
Dear Dr. Dressler,
I have posted twice but I guess I forgot to put in the website that I posted to. At any rate our border collie/shepherd mix, Cassie has a mast cell tumor located on her leg where the hock meets the thigh. Clear margins cannot be achieved and there would be a big hole where the tumor was. She would need a skin flap. The tumor has been graded as a I and I have decided not to put her through the agony of an operation. She has two spots showing up on an ultrasound and Xrays. One is by the spleen and the other is near the lungs. I am going to have a needle aspirate done on the one by the spleen. I guess that chemo and radiation therapy would be the way to go. I live in Ottawa, Canada and it would be so expensive for me to get the food and supplements that you have on your website. Can you suggest a protocol for my Cassie as I am so bewildered at this point I don’t know what to do. The vet wants to amputate her leg. This is riduculous I think. I cannot get a second opinion from other vets because she is already involved with the one I have. They are very pickey here and I already lost one dog to mast cell tumors. She suffered a great deal because the vet did not get the proper margins and did not stitch her up properly. I am so scared that this is going to happen again I am beside myself. If you could give me some suggestions I would very much appreciate. Thank you.
Joanne
Joanne, I feel for you out there. You can get a lot of the supplements on-line from human vitamin sites.
Find out if indeed we have metastasis, first of all, which you are doing.
How old is your Cassie?
A grade 1 is not often dangerous, with some exceptions. The fine needle aspirate will help make that determination. Also buffy coat smears and bone marrow biopsies can help see if you have spread.
You should discuss with your vet intralesional Triamcinolone (which they have sitting on their shelf most likely already). They inject the mass with this form of corticosteriod and often you can shrink the tumor. I would of course consider cimetidine and benadryl for help with the body effects mast cell tumors can have. Also show your vet the luteolin post to consider.
D
Hi Dr. D,
Rosie’s surgery was good and bad. They were able to get 100% of the cancer on her belly and the MCT on her muzzle did not result in clear margins. We are continuing on benadryl twice a day and prednisone. Our vet suggested CCNU but even after all of my research I am still unsure. Every tumor she has had removed is a grade 2. This is the first that they were unable to get clear margins. Does CCNU help current and prevent new tumors? Is there research on this? Are the risks high? We are also considering K9 immunity but I’m not sure if she is on pred and CCNU if this is too much of an overload?
Any advice would be wonderful. Thank you for this service that you offer.
Hi Ashley,
the most favored chemo protocol with mast cell tumors, in my opinion, is prednisolone with vinblastine. That is a better combo as far as I am concerned. You should be in touch with an oncologist if possible.
Also in my opinion, I doubt that K-9 immunity is too much of an overload, but every dog is different and I cannot give individual dog advice. You should discuss luteolin with your vet as well (see that blog post).
D
Hi Dr. Dressler! Thank you so much for having the most comprehensive source of advice on the internet with personalized and thorough responses.
Like many of the people on here, I am trying to figure out the best way to support my wonderful dog, Fallin– my chocolate lab who recently had a Grade 2 mast cell tumor removed with clean margins (not as wide as they would have liked, but they say they got it all). My vet recommended that I just closely monitor Fallin for tumors to return. However, I hate feeling that it is just a waiting game and there is nothing else that I can do.
I would like to get her on a healthy diet with the appropriate supplements in order to boost her immune system to be proactive and hopefully keep tumors from not coming back. Do you have any suggestions as to a specific diet and supplements to support me on this plight?
I currently bought Blue Buffalo food, which is organic and has more natural products than the dry food I was using before. Before that, I tried to make a homemade, carb free diet (“cancer diet”), but her stomach did not take well to it even when I tried to ween her onto it slowly with the dry food. I also started to give her the Budwig’s protocol that I read about online, which is the organic cottage cheese blended with flax seed oil.
Besides food, I am especially interested in a specific regiment of supplements, vitamins, etc. I have done some searches online, and there is just so much out there that I don’t know where to begin! I don’t want to go crazy and buy everything!!
Could you help with ideas on diet and supplements? Fallin will be 4 years old in April and is around 80 pounds of love! =)
Thanks so much,
Amy
Amy, I cannot give specific recommendations to individual dogs. I am sorry to here of this bad news with your pooch. Consider ND food (prescription), but mix in over 2 weeks!! Blue buffalo in my opinion is a good food overall, but less carb restricted than I would like for dogs with cancer. There is little harm in adding some low or non fat cottage cheese with flax oil, although omega 3’s are more accepted.
I would have you do some reading on some of the posts here:
luteolin
curcumin
EGCG
omega-3 fatty acids
That is a start!
D
Dr Dressler,
Our five and half year old Golden girl has been diagnosed with Grade 2 Mast Cell Sarcoma on her tail, a lump was found and we had it removed with histo being done to see what was the cause,at the time of the lumpectomy she was give an injection of antihistamine prior to the surgery as I requested her surgeon to do, to many years working in a vet clinic has made me concerned about the ‘unknown’ and Mast Cell in particular. My fears were true and Mast Cell Sarcoma, Grade 2 was found. Per recommendation of her vet her tail has been amputed with histo being done and the results came back as clear margins, no cell found. X-rays were done of both chest and abodmen at the time of her surgery to check for ‘mets’ both these x-rays were clear of metsates at this time and as she was spayed at the same time a visiual examine was also done with the liver. Spleen, kidneys and inguinal lymph nodes looking clear and nornmal. She is in otherwise very good health. We have started her on the K9 Immunity/Trans Factor supplements also. She has always been on a Low Carb (currently Taste of the Wild) plus raw diet but I am still wanting to see just what else can be done to keep our girl happy, healthy and with us for a lot more years. Can you give me any suggestions for future treatment/care? I thought I read someplace that there was a blood panel that could be done to show if the Mast Cell was in her blood but can not find any write up on this. I work at a vetenaray clinic and her Doctor is very open to any suggestions and information that I can find. He has said that in the past with his other patients who have had Mast Cell if the margins are good that he has really done nothing and the dogs have done very well and lived good long lives with few if any reoccurances. But I just want to see what others have done? Should we think about Chemotherapy or what treatments, food, supplements, etc with their doggies. And with a prognosis of ‘Gaurded’ it just scares me to think that she could be gone in a short time, it just doesn’t seem possible that one so young could have this problem but then my mind also knows that cancer or any diease does not pick a pet because of it’s age or anything, it just does what it does. Thank you for your time and help with our girl. Shirley
Shirley,
good work on advising the benadryl injection. Raw diets for cancer dogs is usually a bit of a no-no. Sometimes the immune system is not up to par and the microbes in the packaged meat may be too much.
The blood test you are talking about is called a buffy coat smear, good idea.
The conventional perspective is to do chemo, but many vets do not advise it for grade 2, since sometimes it turns out fine. Other times not so, so we have a quandary. There is no right answer. If you decline chemo, advise frequent full body cancer checks (ultrasounds, cbc, chem panel, urinalysis, chest films, buffy coat smea, physical exams, aspirates as appropriate) frequently as decided by you and your vet.
You might want to discuss EGCG, Curcumin, krill and Luteolin with your vet.
D
Ashlee,
ask as many questions as you can. The more familiar you are with concepts the better off everyone is. You will also come to appreciate there are limits to our knowledge.
I like luteolin, curcumin, krill oil as a good starting point.
Consider FP food (hills) as one of many options.
D