Canine Mast Cell Tumors: JD’s Mast Cell Tumor Diagnostics, Strategy, and Treatment

Nobody can identify a bump just by looking at it; not even a veterinary oncologist.

Do you think you know what a mast cell tumor looks like? Can you tell a benign lump from cancer? You cannot unless somebody examines the cells it contains.

Canine Mast Cell Tumors: JD's Mast Cell Tumor Diagnostics, Strategy, and Treatment

JD’s mast cell tumor diagnosis

Recently, we found three bumps on JD. One of them was clearly a skin tag. The other two could not be identified by simply looking at them. Following the golden rule, we had them aspirated.

One of them turned out being a benign lipoma, the other, however, a mast cell tumor.

My homework

I had a basic idea what mast cell tumors are but I didn’t feel it was enough now when we were actually dealing with one. I went on to do my research. One of the first things I did during that process was getting the Dog Cancer Survival Guide. It is written by Dr, Demian Dressler, DVM, and Dr. Susan Ettinger, DVM, a veterinary oncologist.

Dog Cancer Survival Guide covers a full spectrum approach to canine cancer, combining state of the art modern medicine and holistic approach.

If I was going to tackle cancer of any kind, I was going to attack it from all sides.

When the lab results came back identifying one of the bumps as mast cell tumor, I know surgery was the next step.

Most canine mast cell tumors are curable with surgery

If everything went just right, getting cancer out could be all that was needed.

It was still very small (size of a smartie) and not angry-looking at all, just a little inconspicuous bump. We were shooting for a cure.

Achieving clean margins

The main goal was removing all cancerous tissue.

Unfortunately, cancerous cells don’t come with a big tag and they don’t come confined strictly to the lump itself. Getting clean margins, which means removing ALL of the cancerous cells, was going to be tricky. The rule is to cut out 2cm of tissue all around the tumor. On the tarsus, where JD’s tumor was, there is very little of any tissue. If we couldn’t get clear margins, we’d have to consider following radiation therapy.

We had a big debate on getting clean margins versus being able to close the wound.

Both I and our vet felt that clean margins, if possible, are the main goal, even if it meant having to do a skin graft to close.

Notes from the vet in response to my questions: “For margins, we need 2 cm around laterally and one fascial plane down. This will not be a problem. I may need to do a lateral releasing incision, but I’ll have a better idea at the surgery. We can also use flaps or grafts.

Potential further steps

We will know about local radiation after the histology comes back, but at the size, it is now I seriously doubt we will need radiation therapy.

If indeed we need further therapy, radiation is by far the best choice, no question.

The grading system is entirely up to the histologist, but most do either the new system or both. We will be sampling the local lymph node (popliteal) and taking 3 view radiographs (left, right and v/d) of the chest, and an ultrasound of the abdomen. They always include the mitotic index in addition to margin evaluation and staging. Many will include literature on prognosis, but generally, if the grade comes back greater than 2, or a suspicious 2, then I forward the case to an oncologist. They would be the ones directing the radiation regardless.

You could add turmeric, and possibly a stasis breaker formulation – I would like to see the histology first.

I do want to tell you that based on experience, distal limb cutaneous mast cells growths are by in large, MCT 1, unless they are left for years and years. This one is nice and small, and we are getting it off early. So I don’t want you to worry too much until we know for sure what we are dealing with. JD needs our good energy right now! 🙂

Oh, and I will be pre-medicating with diphenhydramine (antihistamine) before the surgery.”

Having to do a skin graft ended up being the case – skin was taken from JD’s shoulder and sutured on the wound. Then the removed tissue was sent to the lab.

Successful surgery

We did indeed achieve clean margins.

Even though JD looked like after a motorcycle accident, having a chunk of skin taken from his shoulder and implanted onto the would on his leg, even though it all looked very nasty and unhappy, and even though it’s still healing, I believe that getting clean margins was well worth it, particularly as it turned out being grade I tumor, for which complete excision can be all the treatment needed to achieve cure.

All the cancer was removed.

JD also got x-rays, ultrasound, and a lymph node aspirate to see whether there were any further signs of cancer other than the lump itself. All this was done before the actual surgery because if it was found that it has spread, we might not have attempted the surgery in the first place. All of that looked clean.

We are done for now.

We got it all out, it was grade I and mitotic index was 0. Of course, we’ll keep checking for any future bumps and continue semi-annual wellness checks.

Related articles:
JD’s Biopsy Results Revealed Mast Cell Tumor: You Don’t Know What the Bump Is Unless You Look at the Cells

Further reading:
Your Dog Has a Mast Cell Tumor, Now What

Categories: CancerConditionsMast cell tumors (MTC)Real-life Stories

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Jana Rade

I am a graphic designer, dog health advocate, writer, and author. Jasmine, the Rottweiler of my life, was the largest female from her litter. We thought we were getting a healthy dog. Getting a puppy from a backyard breeder was our first mistake. Countless veterinary visits without a diagnosis or useful treatment later, I realized that I had to take Jasmine's health care in my own hands. I learned the hard way that merely seeing a vet is not always enough. There is more to finding a good vet than finding the closest clinic down the street. And, sadly, there is more to advocating for your dog's health than visiting a veterinarian. It should be enough, but it often is not. With Jasmine, it took five years to get a diagnosis. Unfortunately, other problems had snowballed for that in the meantime. Jasmine's health challenges became a crash course in understanding dog health issues and how to go about getting a proper diagnosis and treatment. I had to learn, and I had to learn fast. Helping others through my challenges and experience has become my mission and Jasmine's legacy. I now try to help people how to recognize and understand signs of illness in their dogs, how to work with their veterinarian, and when to seek a second opinion. My goal is to save others the steep curve of having to learn things the hard way as I did. That is the mission behind my blog and behind my writing. That is why I wrote Symptoms to Watch for in Your Dog, which has turned out being an award-winning guide to dog owners. What I'm trying to share encompasses 20 years of experience.

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