Dog Cancer - Diagnosing and Treating Cancer in Dogs

Is cancer in dogs common?

It's very common. It's probably one of our most frequently diagnosed diseases.

Dr. Ashly LaRoche
Animal Hospital of Statesville

What are the common types of cancer in dogs?

There's hemangiosarcoma, which is a cancer of your spleen and your liver. And there are certain breeds we see that in. Sometimes we tend to see it more in German Shepherd dogs, Golden Retrievers, and Labrador Retrievers. Any dog can, of course, present with this kind of cancer, but there are a few breeds that tend to be overrepresented. There are also many skin-type cancers. Mast cell tumor is a prevalent one that we see. It's a skin cancer that tends to be solitary, but there can be multiple nodules in the skin. And on occasion, it can be quite aggressive, so catching it early is essential.

We see a variety of different tumors, including squamous cell carcinomas, which is a tumor of the skin and the mouth. We see melanomas on the skin and in the mouth. Male dogs get testicular tumors, and mammary tumors are prevalent in female dogs that have been spayed later in life. Osteosarcoma is a very aggressive malignancy of the bones. We see lymphoma, a cancer of basically the lymph system or the lymph nodes, part of the immune system, just like in humans. We also see bladder tumors. Again, we see all kinds of cancer in dogs.

What are some signs and symptoms of cancer in dogs?

Sometimes you can see simple things like weight loss and lack of appetite. There are many lumps, and bumps dogs can get. Most of them are benign, but still, without checking them and running a straightforward test called a fine needle aspirate, we don't know for sure.

How is early detection and diagnosis of cancer in dogs so important?

Most cancers are more amenable to being removed like tumors. And if they're detected earlier, when they're smaller, they're less apt to have spread. If you catch them early, you can either treat them with surgery or chemotherapy, depending on the tumor types. Not having the cancer spread and even cure rates and things like that are often based on how soon it's caught.

What are some other ways that a veterinarian would diagnose cancer in a dog?

Fine needle aspirate is where we stick a needle in a solitary tumor, for instance, or multiple tumors that we can see and feel. And then, we take that sample, put it on a slide, and look at it under the microscope. Sometimes that in and of itself is diagnostic. Sometimes we sedate the pet, and we take a little piece of the lump or bump, and we send it to the laboratory, and they do what's called histopathology on it. They analyze it and give us a diagnosis of what it is and sometimes how aggressive it is. In some cases, we remove the whole tumor and do histopathology. They can let us know whether it had reasonable margins, or whether we got it all, and what its recurrence rate might be. Sometimes we can diagnose cancer with things like x-rays and ultrasounds. We can find it and see it, for instance, if we x-ray the chest and see multiple tumors in there. That's an indication that that dog has metastatic disease, so we start looking for a primary tumor somewhere else.

If you still have other questions and you'd like to reach out to us, you can call us directly at (704) 872-3625, you can email us, or you can reach out on Facebook. But please do reach out, and we'll get back to you as soon as we can.

Dog Cancer - FAQs

Dr. Ashly LaRoche
Animal Hospital of Statesville

Can dog cancer be cured?

Dog cancer can be cured. It depends on the type of tumor, its location, and other things like that. As far as chronic diseases go, there's a number of them in dogs, cats, any animal. Cancer is the most likely to be cured or have a reasonable treatment.

What is the cure rate of dogs with cancer?

That's hard to say because it depends on the type of tumor. I don't know that we have an answer for that. There are certain tumors like sarcomas, for instance, that tend to be a little more locally aggressive. If we were able to surgically remove them, that would be a high cure rate for that type of tumor. Then there are other tumors like bone tumors that are extremely aggressive, and we don't cure the dog. We make them feel comfortable for an extended time, sometimes with remote amputations and things like that.

Have there been advancements in the treatment of dog cancer?

Yes, there have been. We do chemotherapy as they do in humans and they do radiation therapy like they do in humans. There have been all kinds of neat immunotherapy or antibody therapy advancements where you have antibodies that can attack the tumors. There's been a lot of advancements in cancer that weren't available 20 years ago.

Is surgery an option for dogs with cancer?

It is with many types of cancer. It depends on the type of cancer, but with certain tumors like mast cell tumors, we can remove them. Depending on the location of sarcomas, we can remove them. Many times, those are curative surgeries. Surgery is often an excellent option for many different types of cancers— not all of them, but many of them.

As a veterinarian, how do you know what type of cancer my dog has?

It depends on several things. Sometimes we can figure out what type of cancer a dog has based on a fine needle aspirate, where I stick a needle into a tumor, for instance, and look at it under the microscope. Certain tumors are relatively easy to diagnose that way, like a mast cell tumor in the skin is an easy one to diagnose that way. We can diagnose some of them in the office. For others, we take a biopsy sample. We take a little piece or the whole tumor in some cases and send that to the laboratory. A veterinary pathologist looks at them and does histopathology and gives us that diagnosis.

Is dog cancer a death sentence?

No, not necessarily. Pretty much every cancer has treatment options, and that ranges from curative surgery to palliative therapies where we keep them comfortable for long periods. Some tumors aren't resectable, or surgery is probably not going to remove the cancer, but it's slow-growing, and we can keep them comfortable for a very long time. And to dispel the myths, we do compassionate cancer care with dogs and cats. We don't want them to feel bad while they're going through chemotherapy, and most dogs and cats do very well on chemotherapy. There's often a protocol for the individual dog, the owner's budget, and the owner's schedule to make the dog feel a lot better and extend their life.

How do I know if my dog is nearing the end of his life if they have cancer?

It's tough to say, and it's a very personal decision every owner has to make. My advice is when your dog is having more bad days than good days or when your dog stops doing the behaviors that make them happy. That's often their interaction with their owners or their pack members. It may be that it's getting time, at that point, that the dog doesn't feel very well and may be getting close, but that is a decision typically that's between you, your family members, and your veterinary team. We have that discussion to see when everybody thinks it's time.

What should I know about end-of-life care?

We do a lot of palliative therapy. We control nausea. We don't want our patients to feel any pain, and we want to have the most positive end-of-life experience between the owner and the patient. We try to make things as painless and as pleasant as it can be in those situations.

Can dogs get all the same kinds of cancers as humans?

I would say they can get most of the same types of cancers that humans get. I'm not too versed in how many different types humans get, but for instance, lymphoma humans get, so many dog owners are familiar with that. Breast cancer, a lot of owners are familiar with that. Dogs can get that. There is some that overlap.

What is dog lymphoma?

Dog lymphoma is a cancer of the lymphocytes, which are an immune cell in the body. They live in the lymph nodes and produce antibodies. The most common lymphoma is where the lymph nodes become rapidly enlarged throughout the body.

What is dog melanoma?

Melanoma is melanocytes or pigment cells that have unchecked division rates, and they get masses. For the most part, we see more melanomas in the dog's mouth area, sometimes around the toenails and around the rectum. They're not necessarily based on UV radiation and light like they are with people in the skin. That's not as common in dogs. They have a nice haircoat. I think that's part of it. We tend to see them in the mouth or the oral cavity and things like that.

What is a dog tumor?

A dog tumor is an inappropriate proliferation of cells. A cell population goes unchecked. They can be tumors in the skin, under the skin. For instance, fat is a common benign tumor called a lipoma in dogs. We'll commonly see that, and they're not always cancerous. Any cell line that decides it wants to divide at an unchecked abnormal rate.

What does a tumor feel like in a dog?

It depends on the tumor. Some are soft and squishy and round like a lipoma. You'll find those in Labrador Retrievers under the skin many times. Some of them are very firm and hard tumors in the skin. You'll see that in certain sarcomas. With bone tumors, you'll see very painful swelling. It just depends, but for the most part, most owners are finding lumps and bumps on the dog, and that's what brings them to me.

How do I stop a bleeding tumor on my dog?

A tumor that bleeds has often been traumatized by the dog itself, bumped, or something like that. Some tumors outgrow their blood supply and then we'll have a center that weakens in the middle because it doesn't have enough blood, and it ruptures out. Use compresses or wrap it and then seek veterinary attention. We'll talk about options as to whether it can be surgically removed at that point.

What is the most common treatment for cancer in dogs, and what are the options available?

I would say surgery is probably the most common treatment option for most. Then we have some tumors that tend to be more aggressive and metastatic. Those will need chemotherapies, and as we had talked about earlier, chemotherapy does not typically make animals sick and feel awful. People think it does in humans, so that's not typically what we want for their last days, months, or years on earth. We want compassionate care. Then radiation therapy is also very common. In tumors like melanomas, for instance, we can sometimes remove them and then do immunotherapy or antibody therapy or vaccine therapy. There are all kinds of things out there that we can do.

Are there any side effects to cancer treatment in dogs?

Some chemotherapy agents can cause changes in the blood parameters and decrease the immune system transiently. Those patients are monitored to make sure that their body is safe to have the chemo. That's one side effect, and you can get nausea with certain chemos, but we try to combat that ahead of time with anti-nausea agents.

How long can my dog live with cancer after treatment?

There again, it depends on the individual case. It depends on how aggressive or advanced the particular cancer is. By the time it's detected, some dogs will live weeks to months, while others will live for years. Lymphoma patients, for instance, can live several years.

How long can my dog live without treatment for cancer?

It depends on the tumor. For instance, sarcomas tend to be locally aggressive tumors of connective tissue. Some dogs will live years with those with supportive care and palliative therapy. It depends on the type of tumor that we're dealing with or the type of cancer we're dealing with, where it is, how big it is, and things like that.

If my dog is going through some kind of cancer treatment, how will I know if they are suffering?

What you would see is they will stop eating for days. They start not doing the behaviors they usually do in interacting with our owners and things like that. Dogs tend to be very social critters with their owner. When they stop caring about their family members, sometimes it's a sign that they're not feeling well.

What should I consider when I'm choosing a cancer treatment for my dog?

That's very individual. Surgery is pretty much the mainstay for many tumors. That would be the one you would choose. Chemotherapy, for instance, often depends on the owner's budget and schedule. I always encourage owners, if they are very interested, to seek a consultation with an oncologist, and they can give you options. There are often options for every budget and every schedule available—not always, but many times there are. You can at least get that consultation to know what your options are.

Pet insurance and twice-yearly exams can help. Then we notate any lumps and bumps that we find. We notate their size. We've done fine needle aspirates, and we have those results logged on records. It's easier for us to detect if things are changing. There are certain benign lumps and bumps where it's OK to monitor and not do anything about. If they're changing, then we start talking about options to investigate further.

Can medications or diet be used to treat cancer?

Yeah. There are many different medications, as chemotherapeutics are medications. Certain tumors like bladder tumors respond to medicine to some degree, or it slows their spread and increase in size. Nonsteroidal anti-inflammatories like Rimadyl can also help with those tumors. Studies show a good quality balanced nutrition and leaner body weight put an animal at lower risk of cancer.

How long do cancer treatments last?

It depends. Surgery is often curative, and so that's the day of surgery and healing, and it's done. With chemotherapy agents for lymphoma, the treatments can vary. Some of them can last many months until the pet goes into remission. Then when they come back out of remission, they start over. It depends on the tumor.

How frequently will your dog need cancer treatments?

In response to treatment, they'll go into a remissive state. A lot of those chemo protocols are done at that point or a little past that. Then we monitor the dog very closely for them to come out of remission. Then a new protocol is started at that point.

Is dog cancer treatment painful?

We try for it not to be. Our rules are, we don't want anybody in pain. We don't want anybody sick, and we don't want anybody starving. We want them to eat. We want them to feel good.

What are the most significant factors in the successful treatment of cancer in dogs?

Early detection is probably our biggest factor; hence annual wellness or semi-annual wellness are excellent things to do.

If you still have other questions and you'd like to reach out to us, you can call us directly at (704) 872-3625, you can email us, or you can reach out on Facebook. But please do reach out, and we'll get back to you as soon as we can.