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.
My beautiful 13-year old Italian greyhound has been diagnosed with having a mass cell tumor on her left rear leg and because of where it is they will be unable to cut out all the cancer. While the surgery and radiation treatment are very expensive (approx $6,000), I am also very, very concerned about the effect of the surgery and treatment and her quality of life. She is currently taking a steroid to see if they can shrink the mass, along with children’s benadryl, and Pepcid. They say her blood tests were very good, especially for her age. She has had a number of other tumors removed through the years and fortunately they were not cancerous.
Can you please give me your opinion if we should go ahead with surgery and treatment, or if anything else can be done to help her.
Thank you
Nancy
Dear Nancy,
the problem with mast cell tumors is that some are killers (not all, but some). I would get a good surgeon to tackle it and get those cells out. You might also consider a biopsy to see what the grade is (which determines how aggressive it is). This would give you the added info you need prior to a big surgery.
I hope this helps,
DrD
Our almost 10 year golden retriever girl has had a number of lumps removed for the past few years. Last week she had 4 removed and a raisin sized black lump removed from a hind foot which appears only about a month old since she is bathed monthly and her body examined for lumps and bumps. We were told only that she has melanoma and that the margins were clear. She takes Rimadyl, Glucosamine, fish oil and flaxseed oil, had hip displasia which was corrected when we adopted her at 9 months. Otherwise, she is a happy with a good appetite, etc. There are mixed reports about Palladia and its efficacy. We are more concerned about quality of life for her. Yet, the only option offered us was the Palladia if available. What is the most appropriate and helpful treatment for her at this point? I have read your other comments and researched the web about all the alternatives. Thank you for getting back to me. Judith
Dr.Dressler, It saddens me to report that the evening of August 19th JOSIE lost her battle with cancer. I am beyond sorrow. My heart is full of pain that this world had to loose such a tender soul such as hers.I may never have that deep of a friendship ever again.She was truly THE ULTIMATE GOLDEN GIRL. I’m getting angry now about a country that can’t do better than this for their pets. We all have a responsibility to demand better research and care for what for some is the most significant relationship they will ever have. Josie was not just our house pet.From the beginning as a puppy she didn’t want to be left behind so she would travel with us everywhere.Josie was content to sit in our seat while we “got our hair cut” or “ran into the store for milk etc.She didn’t care where she was going, just take me for a drive.Sometimes we would get her a dish or cone of fresh vanilla ice cream from the dairy farm. When she wasn’t busy watching over the homefront she was either out training at the Hunt Club to hunt and retrieve birds or she was out in the wild hunting and fetching birds. She absolutely loved life. Whatever, whenever, whoever-She Loved Everything and she loved well and Always with a good balanced energy. She just knew how to act or react in any given situation.My Husband and I are sure that she was here before us and came back to be with us and share our lives.I was Blessed beyond words to have the honor to care for Josie for 5 1/2 years. Rest now Josie for you and I will meet again, soon. XOXO Josie’s mommy, Donna Walker
Dr. Dressler, Thank You for writing your book. I purchased it in June just after we learned that our Beautiful 5 1/2 yo Golden Josie was diagnosed with grade 3 mast cell cancer.Prior to that she had two surgeries and three tumors removed.One clean margin, one not so clean and one removed with a lymph node.We were not told of the severity of her disease at the time and only after searching on the internet did I realize that Josie was going to die soon.We switched her to a raw/rare food diet along with Transfer Factor and nutritional supplements then we found a holistic vet who performs kinesiology and she added some tinctures and detox drops for her food. It was about 3 weeks into that treatment before I realized that she wasn’t treating her for the cancer and Josies belly got hot and reddish/purple and 5 tumors began growing .She is now on LutiMax and 40mg. pred 2x a day and initially they were shrinking.Sunday night they blew up and two have hardened.She is taking something for liver support &.benadryl.Tomorrow we have an appt with a new Holistic Dr.My husband is against any more surgery and I am running out of time to save Josie from a horrible death.I think it is shameful that people who love their pets should have to waste precious time searching for the info to help their loved one.Why isn’t this information out there? The oncologist told us in June that Josie would be gone in 4 months and we should take her home and enjoy the rest of her life with her.She said we shouldn’t make changes to her diet because in the larger picture it wouldn’t matter.Josies favorite treats are cheddar cheese and vanilla ice cream.The oncologist said that if she enjoys it then give it to her.Those treats would feed the cancer and kill her faster! Well, in hind sight maybe she was right.Josie’s recent flare-up looks bad and after the pred and lutimax I don’t know what else there is to try.Please don’t stop spreading the word about alternative care. Everybody needs to be educated. Thank You again.Donna Walker
Dr. Dressler,
My basset hound, Georgie, is 6 years old and just had surgery for 3 mast cell tumors. (one on chest, one near profuse and one on side.) He previously had surgery for one on his chest 2 years ago. He had puppy strangles when we got him and in the past 2 years he has had a swollen muzzle and then a swollen leg which each led to a trip to the emergency clinic. We are childless and are so very blessed with him. He is truly our life. The vet has spoken to an oncologist about starting chemo but quality of life is of the utmost importance so that may not happen. What spice/supplement regimen do you suggest. I just started him on a half tsp of tumeric. Whatever you can suggest will be greatly appreciated- especially other clinics or doctors or trials. We just love him so much.
Many thanks.
Dear Dr. Dressler,
Our 4 year old boxer had a fairly large grade 2 mast cell tumor removed from his lower front leg last year, and clean margins weren’t obtained. Our vet had wanted to go back in shortly after but decided against it when it healed up really well. Now there appears to be a soft, fatty lump above the surgery site. This area also swells up quite large from time to time, but only for a day or so before returning to it’s present state. We’ve gotten another needle biopsy done and are awaiting the results. My question is, since the surgery was 17 months ago, wouldn’t this area be cancer free, and what would cause the occasional swelling? The fatty lump hasn’t grown much in over 2 months, and I’ve read that liposarcoma grows fast, so I’m hoping it is just a lipoma. It doesn’t feel like it’s attached to the muscle either. Thanks, Ray
My Rottweiller/lab cross, Jake, turned 10 in February. That same month, he was diagnosed with squamous cell carcinoma in his toe as well as a stage one mass on his shoulder (I can’t remember the technical name for the mass, but we were told that it is the kind of cancer that generally does not spread). He had his toe amputated and the mass removed. He has recovered well from the surgeries, but we just found out that he has a mast cell tumour between his toes on his back leg (not the foot that had the toe amputated). The cytologist felt it was a stage one cancer. We’re reluctant to put him through another surgery and can’t really afford to keep undergoing expensive treatments (we’ve already spent $5,000). My vet suggested trying injections of triamcinolone. Would you recommend this? You also mentioned lomustine in your blog. Would this be something we should try in conjunction with the the triamcinolone? I realize that he has reached the life expectancy of a dog of his size, but I would like to give him at least a few more months if possible. The thought of saying goodbye is heartbreaking. Any advice would be greatly appreciated. Thanks – Rosanne.
Dear Rosanne,
So sorry to hear about Jake.
options I would consider (under veterinary supervision)
1. Apocaps
2. have your vet contact Dr. Albert Ahn at Ab sciences to see if Jake qualifies for compassionate use of masitinib
3. topical neoplasine
4. diet changes and the tons of other things in the Guide.
Best,
Dr D
Dear Dr. D
I would love to get your opinions on Nonconventional treatment I have a 6 year old American Bull Dog diagnosed with MCT Level 2 she has had 6 Tumor removals and still has several small ones on her. (Face, legs, neck) I did take her to the Oncologist where she went under treatment of Palladia. After several thousand dollars later she still has this cancer we stopped treatment due to the lack of funds. Last month I brought her back to my vet to have several tumors removed ( with a 3 month lapse) and consulted with the Oncologist today, she is stating that we can try Lomustine 60 Mg (1 40 mg, 2 10 Mg) or Vinblastine. and we wont even talk about the cost. I LOVE MY ABBEY. and want to do the best for her she is still young and full of energy. I have searched the Web for ideas and came across Nonconventional Treatment and was wanting your opinion of it.
Thank you so much for a response.
Cindy Dougherty
Dear Cindy,
I am so sorry to hear about this. You may want to consider getting your vet enrolled in the compassionate use program at AB Sciences in New Jersey and access the pre-FDA approval drug masitinib, which has helped it cases like your dog. Next, dogs need help supporting normal apoptosis levels, as well as helping to stabilize mast cell release of histamine:
https://www.dogcancerblog.com/blog/mast-cells-and-luteolin-in-cancer-treatment-part-1/
https://www.dogcancerblog.com/blog/apoptosis-and-dog-cancer/
apocaps was designed with luteolin to support normal apoptosis levels.
Consider dietary changes:
https://www.dogcancerblog.com/blog/diet-for-dogs-with-mast-cell-tumors/
That should get you started. There is more in the Guide, of course, but that’s a good start.
Best,
Dr D
DR D.
I WOULD LIKE SOME ADVICE ON ORAL NEOPLASENE FOR MY 5 YEAR OLD GOLDEN-MAX.HE HAS A FIROSRCOMA OF THE MUZZLE X8 MO.HE IS DOING VERY WELL-EATING, PLAYING, ACTING NORMAL.WE SEE A VET ONCOLOGIST THAT HAS HIM ON PALLADIA AND RYMADYL 75MG. X2 MONTHS.THE MASS SEEEMS FAIRLY STABLE ACCORDING TO HER, BUT HAS HAD SOME SLIGHT INCREASE FROM 2 WEEKS AGO.I WOULOD LIKE A MORE AGGRESSIVE PLAN.SHE SAID PALLIATIVE RADIATION-BUT I DO NOT HAVE THE $2500 THAT IT WOULD TAKE, AND WITH THIS TYPE OF TUMOR SHE SAID IT PROBABLY WOULD NOT SHRINK BUT WOULD SLOW THE GROWTH.I HAVE HIM ON 5000MG OF FISH OIL, VARIETY OF MUSHROOMS, MULTI VITAMIN,EVO DOG FOOD, AND WOULD LIKE TO START ON EGCG AND LUTEOLIN ROTATED EVERY 2 WEEKS.I KNOW IM NOT SUPPOSE TO MIX THE TWO ACCORDING TO YOUR BOOK(WHICH IS FANTASTIC!).THE ONCOLOGIST IS VERY TRADITIONAL AND I FEEL I HAVE NOTHING TO LOOSE WITH MAX.HE ONLY 5 IN GOOD SHAPE AND HEALTH, OTHER THAN THE FIBROSARCOMA OF HIS NOSE, WHICH DID NOT SHOW ANY SIGN OF METASTIZING TO LUNGS,LIVER, OR LYMPH.I HAVE BEEN READING ABOUT ORAL NEOPLASENE, AND WOOULD LIKE TO KNOW WHAT YOU THINK ABOUT USING THE ORAL(DO NOT WANT TO TOUCH THE TOPICAL DO TO LOCATION OF SINUS AND EYES).CAN I USE THE ORAL WITH PALLADIA?OR IF MASS GROWS MORE SHOULD I DROP THE PALLADIA DO TO ITS WEAK OUTCOMES THAT I HAVE BEEN READING ABOUT AND TRY THE ORAL NEOPLASENE.I KNOW YOUR TIME IS VERY VALUABLE AND SHORT WITH SO MANY BLOGS AND E-MAILS, BUT I WOULD TRULY APPRECIATE ANY ADVICE OR COMMENT.THANK YOU FROM ME AND MAX!
Dear “Dog Cancer Vet,”
I’d just like to get your opinion on my 8 year-old cockapoo Mandy. We recently learned that she has a Grade 2 MCT on her back right leg. Actually, we had been concerned about the lump on her back leg for a year and a half and we had our vet look at the lump on two different occasions. Both times, he told he he thought it was just a cist and not to worry. So, we trusted his judgement and didn’t worry. Then,a month ago, we noticed another growth underneath on her chest. This time, a different vet at the same clinic aspirated the growth and saw some round cells in the slide. So, per her advice, we had Mandy undergo surgery to remove the growth on her chest and, at the same time, we had the doc remove the lump on the back of her leg.
We got the pathologist’s report on Monday, only to learn that the growth on her chest was just fatty tissue and the lump on the back of her leg is a Grade 2 MCT. Naturally, we were upset…but more so at our vet for not aspirating and detecting the lump almost two years ago! The report also said that the MCT has dirty margins – but they may only be “dirty” because the vet didn’t know he was dealing with a MCT in the first place and he didn’t cut a wide enough margin around the tumor. He only cut 1/2 centimeter instead of 2-3 centimeters.
The report did have some good news – namely, that the mitotic index is less than 5. So, I guess that means we’re dealing with a “low-end” Grade 2.
My wife and I (and the vet) were surprised to hear about the tumor – primarily because Mandy is such a healthy and happy dog, even though she’s had this tumor in her leg for nearly two years.
After talking to the vet (who in turn talked to the oncologist), it seems like our best course of action is to perform another surgery on the leg, in the hope that this time around they will be able to cut more tissue and find clean margins.
However, there is some concern that even if they perform the second surgery, the pathologist won’t be able to determine conclusively if there are “clean margins.” I don’t quite understand why they wouldn’t be able to tell. Do you know why?
Before making Mandy undergo another surgery, we were thinking of having an ultrasound performed on her, to determine if the mast cells have already spread to the spleen and liver. If that’s the case, then there would be no point in going ahead with surgery.
But, if the ultrasound comes back negative and we do the surgery, I think we will go ahead with radiation treamtent on the leg. I really don’t want to put Mandy through that but, like I said, the vet is telling me that even if they get clean margins this time around, it wouldn’t rule out the possibility of some mast cells still being inside her leg.
What would you advise?
William
William
the ultrasound is a good idea. Painless, good information. If the scan is clean a wide excision, as you brought up, is a very good idea. Vaguely 90% of grade 2 mast cell tumors are cured with a wide excision (no radiation). Median survival time of dogs receiving conventional veterinary care with grade 2 mast cell tumors having a mitotic index under five is 70 months. Mandy is 8 years old. 70 months added on to that is 13.5-14 years of age. This is perhaps a year under average life expectancy (as a guess) for a dog like yours, in other words, close to a full life. Bottom line, I would look at these stats and decide whether radiation makes sense for you in the overall analysis of life expectancy and median survival times.
“However, there is some concern that even if they perform the second surgery, the pathologist won’t be able to determine conclusively if there are “clean margins.”” This is due to micrometastasis:
https://www.dogcancerblog.com/blog/dog-cancer-what-is-micrometastasis-and-why-do-we-care/
Hope this helps,
Dr D