Mast Cell Tumours In Dogs: What You Need To Know!

Understand this common cancer and find inspiration in Pimmy's story. As a Mast Cell Tumour (MCT) warrior, Pimmy shows us how early detection and the right care can make all the difference. "Hey there, my furry friends! My journey, especially after my Mast Cell Tumour (MCT), taught me the true meaning of self-care. It showed my paw-rents the power of good, natural food in a pup's recovery. That's why Mom and Dad created Pimmy's Healthy Dog Treats NZ! Our natural, human-grade treats are crafted with love and care right here in Christchurch, NZ. They are made with wholesome ingredients for your pup's ultimate well-being, because good food truly equals feeling your absolute best! Let's all enjoy a happy, healthy life together. Love, Pimmy."

Understanding Mast Cell Tumours!

This is me, Pimmy

"Right, my friends, listen up! Pimmy here! I'm sharing all the cool stuff I've learned on my wellness adventure. You know, I've been doing my homework—lots of internet digging and asking my awesome vet, Diana Weir D.V.M., right here at Merivale Papanui Vets in Christchurch! And guess what? I even got tips from my old vet back in Argentina, Dr. Analia Perez, from Clinica Veterinaria VET. They helped me understand what these pesky Mast Cell Tumours in dogs are and how to get better. But remember, every pup is unique! So, please, go see your vet! They'll know exactly what's best for your furry friend. I'm just sharing what helped me, hoping it can help you, too! Sending tons of tail wags and love!"

This was my vet measuring my tumour.

A Mast Cell Tumour (MCT) is a type of malignant (cancerous) tumour consisting of mast cells. They are the most common skin tumours in dogs, accounting for 7–21% of all skin tumours. While they typically form as nodules or masses in the skin, they can also affect other areas of the body, including the spleen, liver, intestine, and bone marrow. Most dogs with an MCT develop only one tumour.

Important: An MCT can easily be mistaken for a wart or a lipoma, which is a benign fatty tumour. This is what happened to Pimmy, which is why it's so important to have your veterinarian check your pup as soon as possible for any lumps or bumps you may find. Early detection is key! It's also recommended to have routine check-ups to look for any masses on the skin. You should make an appointment to see your vet if you find:

• A new skin mass.

• A known mass that has changed in size, texture, or colour.

• An unexplained allergic reaction or hives.
  

What Causes Mast Cell Tumours In Dogs?

The exact cause of MCTs—or any cancer—is not straightforward. Most seem to be caused by a complex mix of risk factors, some environmental and some genetic. Several genetic mutations are known to be involved, with one well-known mutation affecting a protein called KIT, which is involved in cell replication and division.

"Okay, so, guess what? This super cute pup right here is a mix of Cocker Spaniel and Mini Golden Retriever! And get this, according to all the stuff my Mom and Dad have been reading, that means I'm one of those breeds that are more likely to get those pesky MCTs. Ugh, right? Pfff!"

While any breed of dog can get an MCT, some are more susceptible. These include Boxers, English Bulldogs, Boston Terriers, Pugs, Golden Retrievers, Cocker Spaniels, Schnauzers, Staffordshire Terriers, Beagles, Rhodesian Ridgebacks, Weimaraners, Chinese Shar-Peis, and Labrador Retrievers. Affected dogs are usually older, with an average age of 8–9 years.

Recognising the Signs of a Mast Cell Tumour In Dogs!

"All right, pals, let me tell you... My Mom and Dad are the best! They're always giving me cuddles and pets, you know, touching me all over. And boy, am I glad they do! If they didn't, I might not have caught that sneaky little bump on my chest. They found it, and boom! Right to the vet at Merivale Papanui Vet! Seriously, thanks to them, I'm doing great! That's why I always talk about early detection; without it, my tumour wouldn't have been detected on time."

Mast Cell Tumours can occur anywhere on the body and vary in appearance. They can be a raised lump or bump on or just under the skin and may be red, ulcerated, or swollen. A key sign is that the tumour may appear to fluctuate in size, getting larger or smaller even daily. These size changes can happen spontaneously or when the tumour is agitated, which causes degranulation and subsequent swelling due to the release of histamine.

When degranulation occurs, the released chemicals can enter the bloodstream and cause problems elsewhere. These may include:

• Vomiting, loss of appetite, and lethargy due to stomach or intestinal ulcers.

• In very rare cases, a serious, life-threatening allergic reaction called anaphylaxis.

• Although uncommon, the cancer can spread to internal organs, causing enlarged lymph nodes, spleen, and liver.

How an MCT Is Diagnosed in Dogs!

"Alright, so, get this! This nasty MCT was playing tricks on us! My vet took a peek and was like, 'Oh, it looks like it's just a little fat bump!' (These fat bumps are called Lipomas.) But, you know, my Mom and Dad, they wanted to be super sure! So, the doctor did this thing called FNA, a fine-needle aspiration. Basically, poked it and sent it to the lab."

MCTs have been classically called "the great pretenders" because they may resemble an insect bite, a wart, an allergic reaction, or a less serious skin tumour. Therefore, any new lump or bump you notice should be evaluated by your veterinarian.

An MCT is typically diagnosed using fine-needle aspiration (FNA). This involves using a small needle to suction a sample of cells directly from the tumour. The sample is then placed on a slide for a veterinary pathologist to examine under a microscope. If a diagnosis of MCT is made, your veterinarian may recommend a tissue biopsy (a surgically removed sample) to indicate how aggressive the tumour is. They may also recommend a prognostic panel on the tissue sample to provide valuable information on the genetic makeup and likely progression of the tumor.

Understanding the Prognosis and Grading!

"Ugh, you guys, this part is the worst!. So, remember that little poke thing? The Fine-Needle Aspiration (FNA)? Well, it hadn't even been a week, and my Mom got this super sad phone call. My vet was on the other end, and she said they had the results already. And guess what? Not good. I had an MCT on my chest! Mom was, like, totally heartbroken. She couldn't even hear what the vet was saying after that, except something about me... You know... I had to go for surgery and many more things about my condition. Pfaff, just thinking about it gives me the creeps!"

The behaviour of this tumour is complex and depends on many factors. When a biopsy sample is examined, a pathologist assesses how aggressive the cancer is based on several criteria. The tumour is then graded from I to III, with Grade I being much less aggressive than Grade III. Higher-grade tumours have a greater tendency to metastasise (spread to other parts of the body).

Another system classifies MCTs as either high-grade or low-grade. The prognosis is typically less favourable if the tumour:

• Is located at a junction where the skin meets mucous membranes (e.g., the gums).

• Has a high number of actively replicating cells when viewed under the microscope.

• Is found in a patient who is one of the susceptible breeds.

How Mast Cell Tumours In Dogs Are Treated!

"Okay, so, Mom was a total wreck! Dad had to ditch work and zoom over to the vet to double-check everything and figure out what to do next. They gave him all this paperwork for my surgery, and I was scheduled for the "big day" on 29th July, 2024! And get this, I had to do all this pre-surgery stuff! No munchies after 7:00 pm the night before and barely any water after 7:00 am on surgery day! Then, they took my blood for tests before noon, and Mom and Dad had to wait until 4:00 pm to pick me up! Wow, talk about a wild ride!" For lower-grade tumours with no evidence of spread, surgery is likely the best option. Surgical removal provides the best long-term control, with chemotherapy rarely required. However, for higher-grade tumours, a combination of surgery and chemotherapy is often recommended. Radiation therapy is another option if the mass is not in a suitable location for surgical removal.

Important: You should avoid touching or manipulating the tumour, as this can easily trigger degranulation. Do not allow your dog to chew, lick, or scratch it, as this may also cause degranulation, leading to further swelling, discomfort, or even bleeding.

Pimmy's Story: The Surgery and Recovery

Here I am after surgery!

"Okay, so it was my surgery day! Dr Tim Nottage B.VSc, a super cool vet surgeon from Merivale Papanui Vet, did it! He was so nice to my Mom and Dad, and he explained everything. He said the surgery went great! And get this, he thought the tumour was a Grade I, which is like, the least scary one! Thank goodness, right? But he did have to take out a lot of extra stuff around it, just to be safe. Now, we had to wait again, like, forever! Because they had to send a piece to the lab for a biopsy, and that takes about two weeks, because they don't do that stuff at the clinic. Phew, talk about waiting! The biopsy results finally came out to confirm the tumour was grade I and I'll be all right, yay!"

"So after my surgery, I get to go home! They gave me these little pills, antibiotics and pain killers, to help me feel better. Lucky me, I didn't have to wear that cone thing because the bump was on my chest. Mom had to give me the pills on a super tight schedule, and I even had to wake up in the middle of the night! Now, if your pup is picky, I’m not, but I do love cheese! So, Mom used cheese sticks to sneak the pills in, and I never even noticed! Clever, right? Anyway, later on, my vet said the biopsy was grade I, just like they thought, and I was going to be fine! Yay! I hope sharing my story helps you and your furry friend if you ever have to deal with something scary like an MCT. It's tough, I know! But remember, seeing the vet right away is super important. And if you need surgery, you've got this! Stay strong, keep your tail up, and know you're not alone. Sending lots of love! - Pimmy."

A Message of Hope!

We know firsthand how difficult a positive MCT diagnosis can be and how confused you, as a pet parent, might feel. The first step is to get support from your vet as soon as possible and ask as many questions as you can, even if you feel they are silly. Be calm, even if it feels hard, because your pup trusts you implicitly and knows when you're not doing well. Embrace this tough experience as a family and ask for support. We send all our love and strength to you and trust Pimmy's journey gives you hope and resilience.

♥♥♥♥

For More Proactive Wellness Tips!

Pimmy's journey is a powerful reminder that every step toward health makes a difference! For more proactive wellness tips for your pup, be sure to check out our other posts:

. Pimmy's Healthy Dog Treats: Your Furry Friend's Favourite Natural Treats!

. Fruits and Veggies: Cancer-Fighting Foods For Dogs!

. Safe Superfoods For Dogs: The Best Fruits & Veggies!

A Little Note from Us: Before trying any new foods or implementing any health or treatment-related changes with your furry pal, it's always best to chat with your vet first. This blog shares some of Pimmy's favourite eats, which have played a big part in her recovery journey after her MCT experience and in keeping her feeling her best. We hope this information is helpful, but please remember it's not a substitute for professional vet or dietary advice. Sending lots of love to your pooch, cheers!

Sources: Information by VCA , Dog Cancer , Pet MD , Hill's Pet Nutrition, Small Door Veterinary