Critter Culture
Helpful to Know the Facts About Tumors in Dogs

Helpful to Know the Facts About Tumors in Dogs

Critter Culture Staff



The mere thought of tumors causes most people to cringe. When the word's associated with the family dog, it can make someone downright ill. Panicking won't help, yet this is the route many take.

If this sounds like you, then it's time to learn the facts. What are tumors? How are they spotted? Are they usually fatal? What are potential treatments? Having these answers will give you a better awareness of how to notice and manage canine tumors.


Understanding tumors

Veterinarian with dog in examination room XiXinXing / Getty Images

In normal situations, cells in the body grow and divide. Old cells die off, and new cells replace them. When something goes wrong with this natural cycle, tumors can develop.

Tumors are abnormal growths made up of extra cells. They occur when new cells keep forming where the body doesn't need them, while old cells refuse to die. This out-of-control situation continues to add mass to the area since the defective dividing cells have nowhere to go.


Benign tumors

Dog lying on woman's lap at home Westend61 / Getty Images

If your dog has a tumor, the best-case scenario is that it's benign. Benign tumors aren't cancerous; they're simply abnormal lumps of cells that stay in one particular area, lacking the ability to spread.

Benign tumors do still pose a threat. Bear in mind they can creep up anywhere, so if they're in a spot next to a vital organ, the larger they get, the more space they'll occupy, which could eventually prevent the organ from doing its job, leading to catastrophic failure. A benign tumor doesn't always require medical treatment; it usually won't grow back if it has to be removed.


Malignant tumors

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Malignant tumors are cancerous. They form the same way as benign, but these cells have the ability to invade nearby tissues. Over time, they'll also break off and invade other parts of the body, which is known as metastasis. Cancers are named after the site where they originally developed.

In canines, there's a grading scale: 0-IV that indicates how much the cancer has spread depending on the type of malignant tumor. A rating of III, for example, demonstrates that a case is further along compared to one with a II grade.


Causes of canine tumors

senior dog Ahna Meyer / Getty Images

As a whole, there isn't much known about why tumors happen, making it difficult to determine actual causes. Genetics may play a part since some breeds are more susceptible to a specific type of cancer. Age is also a factor, as cancer tends to rear its ugly head in seniors. Environmental agents like location, UV light, viruses, and DNA-altering substances are also probable causes.


Signs of tumors in dogs

dog lying on the bed Carol Yepes / Getty Images

Cancer symptoms dramatically vary from patient to patient, depending on the disease, its stage, and how the body reacts. It's hard to initially pinpoint what's going on with your pooch since signs can often manifest differently or not at all.

Some cancers eat blood cells, while others don't, so anemia may or may not be an indicator. Behavioral changes, seizures, vomiting, bleeding, excess drinking, and swelling are all red flags, but they also signal a wealth of other unrelated issues.


Diagnosing tumors

person looking at dog's fur Liudmila Chernetska / Getty Images

Vets will first do a wellness check on your fur baby, feeling for any tumors and visually observing abnormalities on or near the surface. Lab tests such as biopsies and blood draws will usually, but not always, indicate a problem. Urine samples, needle aspiration, and internal imagery are also viable means for discovery.


Treatment and factors

Client with pet on visit to veterinarian doctor at animal hospital Prostock-Studio / Getty Images

It's important to know that cancer is a general grouping. There are well over 100 varieties of the disease, each requiring unique treatment plans. Aside from this, factors such as the aggressive nature, progression, and symptom severity, also influence the course of action.

Treatments hinge on you as the pet owner, too. This is a personal choice depending on your own decisions and how you want to proceed. Options include surgery, chemotherapy, immunotherapy, radiation, stem cell transplants, or biological therapy.


Common benign tumors

Close up shot of a veterinarian checking on a papilloma wart on dog's elbow Snizhana Galytska / Getty Images

There are a few benign tumors that commonly show up in canines. Lipomas are fatty cell tumors often found in labs, spaniels, pointers, and several other breeds. Papillomas look like warts, are from a virus, and will spread from dog to dog, regardless of breed. They usually manifest in oral regions such as the lips, throat, and tongue but may appear anywhere.


Common malignant tumors

dog with head tumor

Often found in retrievers, boxers, and a few other breeds, mast cell tumors are skin tumors that can be difficult to detect. They can be as small as pimples; some may mimic cysts or lipomas.

Stemming from white blood cells, another type of cancer is lymphoma, which manifests in the lymph nodes. Signs include hardened masses around the knee, jaw, or shoulder. Dogs with lymphoma will often show bouts of lethargy and a disinterest in food.


Recovery after treatment

man sitting with his Border Collie in the living room and using his cellphone Delmaine Donson / Getty Images

Metastasized tumors have a very low rate of being cured, though that doesn't mean they're immediately fatal. Management and maintenance are valuable options that may add years to your pup's life without heavily influencing quality: adverse treatment symptoms and reactions usually aren't nearly as bad in canines as they are in humans. Some therapies can even be done at home, so they're less stressful for your dog.

Tumors caught in an early stage are more likely to be cured. If they're still localized and can be removed, chances are high that your dog will make a full recovery. Just be sure to follow all post-surgical care and maintain routine wellness appointments.


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