Signs Of most Common Types of Cancer in Dogs & Their Diagnosis

Signs Of most Common Types of Cancer in Dogs & Their Diagnosis

Cancer in pets can occur due to environmental, genetic or lifestyle factors. Here are some telltale signs of cancer in dogs you shouldn’t ignore.Just like us humans, our pet children too are at risk of getting cancer and it is important to know the early signs of the deadly disease in them. Cancer in pets can occur due to environmental, genetic or lifestyle factors. From exposure to carcinogens which includes certain chemicals in herbicides or pesticides to second-hand smoking – that lingers in air – and third hand smoking – harmful residue left behind – could increase risk of cancer in your beloved pets. In certain cases, poor dental hygiene could lead to oral cancer in kids which could be easily prevented by following a strict dental health regime. Nutrition and exercise too play a big role in reducing risk of cancer for your furry babies as it ensures healthy weight.

It is complicated to detect cancer at an early age in pets. Let us get rid of a common myth. However, there are 10 signs of cancer in dogs you can look for in your pets. If it is not then, these signs may help detect another medical condition. Also, it is critical to remember that a pet can be very sick inside without showing any sign or symptom outside. Dogs truly are man’s best friend. They are stress relievers for dog owners. However, for dog parents, their dog is the centre of the universe, the reason for their existence, and the reason for their lives.

The care regime evolved alongside the dynamics between pets and humans over time. Pet parents are constantly concerned about their dogs’ physical, mental, and emotional well-being, whether it is through diet, walks, playtime, or stimulating activities.

As ominous as it may sound, another checkpoint on your list as a dog parent is required. Cancer is a common disease in dogs, and as varied as they can be, an early diagnosis can almost always protect our furry friends from harm.

Here are a few more warning signs to look out for in dogs:

As per the National Canine Cancer Foundation, one out of three dogs develop cancer. Cancer can occur in both purebred and mixed breed dogs. There is no age for cancer. Canine cancer can happen at any age. However, it generally occurs in elder dogs. Early detection is the key when dealing with cancer. If you catch cancer in its early stage, you can treat it through chemotherapy, surgery, immunotherapy, and radiation. Here we have the top 10 symptoms which will help you detect cancer in your dog. So, learn to spot the signs here:

1. Abnormal swellings that keep growing continuously

The most obvious sign is a mass that keeps growing under the skin. The surgeon will recommend having it removed and biopsied. It will be easier to decide on the actual treatment process. Once or twice a month, take a few minutes to feel your pet’s body for any lumps, bumps, or abnormal swelling. Check for swollen lymph nodes, which can be a sign of lymphoma. Lymph nodes are located throughout the body but most easily detected around the jaw, shoulders, armpits, and behind the legs. Note the size and location of any bumps or nodes to check any change in shape over time.

2. Non-Healing Sores

The skin wounds do not seem to heal despite oral antibiotics or applying ointments. It could also be a no-healing area near a nail. If your pet has an open wound that is not healing, it could be a sign of something more serious, such as an infection or cancer.

3. Weight Loss

A sudden loss in weight cannot be explained only by a diet. Common causes could include a tumour along the intestine. If there is no change in the diet or food, but your pet is gaining or losing weight, this could be a sign of illness. Weight loss or weight gain can indicate a possible tumour in the stomach. Another related symptom could be chronic vomiting or diarrhoea.

4. Loss of Appetite

A mass along the intestines may make your dog feel uncomfortable. One of the first things a pet will then do is skip its meal or stop eating. Is your pet eating more or less than usual? Are they trying to eat foods they were uninterested in previously? Drastic changes in your pet’s appetite could be a sign of cancer.

5. Unable to Eat or Swallow

A lump in the neck could be putting pressure on the oesophagus the food pipe. A tumour in the mouth or neck can make it difficult for your pet to eat or drink.

6. Bleeding or Discharge

Although bleeding from the nose does not necessarily mean cancer, it is a common sign of cancer of the nose. Consult your veterinarian if your pet experiences any unexplained bleeding or discharge from any opening. Bleeding is a common sign of cancer and other illnesses. Oral cancer can cause gums to bleed. Nose cancer can cause the nose to bleed.

7. Offensive Odour

A foul smell from the mouth can be a sign of oral cancer. Biopsies of a large mass near any opening show that it has cancer. There may be some wounds or nodes from which pus comes out their foul odour gives a doubt of some severe issue. A culture may show different bacteria growing in there.

8. Long-Time Cough

For many reasons, dogs might have a persistent and continuous cough. For younger pups that were recently adopted or placed in boarding, a persistent cough could be a sign of kennel cough. In older dogs, a persistent cough could indicate a tumour near the heart or lung cancer. Because of the bleeding and the pressure on the heart, they certainly face difficulty while exercising.

9. Persistent Lameness or Stiffness

We see lame pets every single day, but luckily, they rarely have cancer. However, bone cancer can cause pain and lameness, along with swelling along the leg. You may find that your pet is limping on one foot or no longer wants to walk or exercise. Persistent lameness or stiffness can be a sign of osteosarcoma or bone cancer.

10. Difficult Breathing, Urination, or Defecation

That could be due to the pressure on the respiratory system, urinary system, and digestive system. A tumour near the oesophagus, nose or lungs can block airways, making it harder for your pet to breathe. Dogs and cats can develop tumours in their urinary tracts, which can make it difficult to urinate. Similarly, they can have trouble defecating or have sustained a foul odour from the rear the mass near the anus might be the culprit.

Most Common Types of Cancer in Dogs

Masses and lumps in dogs are relatively common, but not all of them are cancerous. When a mass isn’t cancer, it is referred to as benign. In most cases, benign masses grow more slowly and don’t spread to other parts of the body, so they don’t pose a serious health threat.

By contrast, cancerous masses are characterized by cells that can multiply. They are known as malignant tumors and may grow rapidly—spreading to other organs and parts of the body, causing potentially serious health problems. How fast cancer grows and where it spreads depends on the type of cancer.

Dogs, just like humans, can get cancer. In fact, about 25% of dogs will develop some form of cancer in their life and about 50% of dogs over the age of 10 will develop cancer. While not an exhaustive list, below are some of the more common types of cancers seen in dogs:

• Anal Sac Adenocarcinoma:This cancer affects the anal glands, which are scent glands located in the rectum­. It can metastasize (spread) to other parts of the body.
• Hemangiosarcoma:This tumor often arises from blood vessels, so it theoretically can arise anywhere. However, it is most found in the heart, liver or spleen. It is an aggressive type of cancer and has usually already spread by the time a diagnosis is made.
• Lymphoma:There are several types of lymphoma that dogs can get, but the most common affects the lymph nodes. It is one of the most common forms of cancer in dogs, but fortunately it is the type most responsive to chemotherapy.
• Mammary Gland Carcinoma:Female dogs have about five pairs of mammary glands, and these types of tumors are more common in unspayed females. Hormones like estrogen and progesterone play a role in mammary development and cancer formation.
• Mast Cell Tumor:This is the most common cancer of the skin, which can be difficult to determine with sight alone since the appearance can vary. These tumors have a variable prognosis and can range from low to high grade—meaning they are less likely or more likely to spread to other areas in the body.
• Melanoma:This type of cancer can occur on the skin or in the oral cavity; these tumors are typically malignant when found in the mouth and require aggressive surgery and/or combination of radiation and chemotherapy. They usually show signs associated with dental disease like bad breath and decreased appetite.
• Osteosarcoma:This is the most common cause of bone cancer in dogs, which is highly aggressive and painful. This cancer commonly affects the legs of larger breeds of dogs.  Treatment often includes surgery followed by chemotherapy or radiation.
• Transitional Cell Carcinoma:This is the most common type of urinary cancer, which usually affects the bladder the most and often causes symptoms similar to a urinary tract infection

Most veterinarians will agree that cancer is a significant concern for canine patients. Although both dogs and humans have roughly a 1-in-3 risk of developing the disease, dogs have much shorter lifespans, so the annual incidence rate in dogs is actually 10 times higher than in humans.

Approximately 6 million new canine cancer diagnoses are made each year in the United States. Unfortunately, the disease is not only common but also deadly. It is the leading cause of mortality in adult dogs, taking more furry best friends than the next five causes of death combined. Why is this disease so challenging to combat, and how can cancer screening provide better early detection?

How DNA Changes Cause Cancer

Put simply, mutations in the DNA of cells can cause cancer. If the abnormal cells have an advantage over neighboring healthy cells, they replicate faster and survive longer. Eventually, they could form a tumor. The cells that make up the tumor continue to develop new mutations to dominate the healthy cells. By the time a tumor is detectable by physical exam or imaging—usually, when it’s about the size of a pea—it typically harbors various populations of abnormal cells, each with its own unique set of mutations.

These unique mutations are a problem. When attempting to treat tumors with methods such as chemotherapy, many cells may respond and be eliminated, resulting in clinical remission; however, some of these cells may have mutations that make them resistant to treatment, allowing them to remain at clinically undetectable levels and fly under the radar. Then, when treatment has eliminated the bulk of the tumor cells, these insidious, resistant cells are able to expand in the absence of competition, resulting in recurrence of the disease.

Why Early Detection and Treatment Is Critical

So, how can veterinarians defeat such a tricky opponent? Success is most likely when they can detect and treat cancer as early as possible. Human medicine has demonstrated that cancer develops over time and that early detection is the key to improved outcomes. This is why mammograms, colonoscopies, and other screening tests are recommended for adults at set intervals starting at specific ages.

Several veterinary medical organizations recognize the importance of early cancer detection in dogs. However, guideline-driven screening protocols for early detection are lacking. The current standard of care for cancer screening in dogs is the annual or semi-annual physical examination and wellness visit. Although these examinations are important for the health of aging patients, they are not enough to confidently detect preclinical cancer. Unfortunately, it’s not until most dogs show clinical signs that cancers are identified—and by then, it’s often at an advanced stage, and long-term control or cure is unlikely.

Once cancer is detected in a dog, a wide range of treatment options exist to help combat the disease. Just like in humans, surgery, chemotherapy, radiation therapy, and immunotherapy are all available tools, and are generally well-tolerated by patients. Some newer therapies even allow for treatment at the general practitioner’s office.

What Early Detection Means

Novel technologies may be opening the door to early cancer detection in dogs, but what does “early” mean and how can it benefit patients?

Early detection can be defined in two ways: detection at an early stage of the disease (early-stage detection) or detection prior to the onset of clinical signs (preclinical detection). Early-stage detection leads to better outcomes for a variety of cancer types, such as lymphoma and hemangiosarcoma, among others.

Dogs who have cancer but have not yet developed clinical signs tend to demonstrate improved outcomes, including patients with lymphoma, brain tumors, and mast cell tumors. Also, since these dogs do not need to be treated for clinical signs or stabilized prior to starting treatment, they are often easier to manage which may result in less emotional and financial burden for their owners. In short, early detection, whether it be early-stage detection or preclinical detection, has far-reaching benefits for dogs, their families, and their medical teams.

General Symptoms of Cancer in Dogs

Dogs with cancer can show multiple symptoms. Some may have a lump or bump, new swelling, a wound that doesn’t heal, swollen lymph nodes, or abnormal bleeding. But many symptoms are nonspecific, including:

• Abdominal distension
• Behavioral changes or other neurological issues like seizures or head tilt
• Coughing or changes in respiration
• Decreased appetite and weight loss
• Exercise intolerance
• Pale gums
• Lethargy
• Vomiting and/or diarrhea

If you are even slightly worried about your pup—especially if you notice a change in behavior or find a new lump—schedule an appointment with your veterinarian for an exam.

General Causes of Cancer in Dogs

Cancer often occurs for unknown reasons and can be influenced by many factors, including:

• Age
• Viruses and infections
• Chemical and toxin exposure
• Genetics
• DNA mutations
• UV damage or other environmental triggers

Cancer Diagnosis

• Once your vet narrows down the symptoms you’re witnessing at home, they will conduct tests. The tests will help them figure out if the tumor or neoplasm is cancerous and what kind of cancer your pet has. The diagnostics performed on your dog will include blood work, fecal samples, and a physical exam. Afterward, they will schedule a biopsy to collect tissue samples. Some may refer you to a veterinary radiologist for a CT scan, MRI, or other digital scans to identify where the cancer is.

Dog Cancer Treatment Options

With the results from the tests in hand, your vet may recommend one or a combination of the following treatments:

• Chemotherapy: The chemotherapy may be localized with injections or intravenous.
• Radiation therapy: A vet uses controlled radiation to treat your dog’s cancer.
• Surgery: Certain cancers can be removed via surgery.
• Drugs: According to the FDA, there are three drugs approved to treat cancer in dogs: Palladia tablets (for mast cell tumors), Stelfonta injections (for mast cell tumors), and Tanovea-CA1 injections (for lymphoma). A fourth drug, Laverdia-CA1 (tablets), was conditionally approved to treat lymphoma in 2021.¹¹
• mmunotherapy: With this newer treatment, a vaccine created using your dog’s tumor cells is injected into your dog in an effort to trigger the dog’s own immune system to attack the cancer cells

Final Words

Again, early detection is paramount. While there is no reason to be paranoid, stay informed, keep your eyes open, pet your dog all over and often, and see your family veterinarian regularly. Whether to detect cancer or any other condition, these are pretty safe recommendations to keep your pet happy and healthy for a long time.

But remember, just because your dog lumps his body does not mean he has cancer. Take him to the vet immediately. People need to be aware of canine cancer, where quick actions can give your dog a second chance to live. Regular wellness exams will provide your veterinarian with the opportunity to check for signs of cancer but, you can take a more proactive approach to your pet’s health by looking for these warning signs regularly. Your furry family members depend on you to keep them healthy for as long as possible. And they will be thankful to you for detecting their cancer early with cuddles, love, and loyalty.

Compiled  & Shared by- Team, LITD (Livestock Institute of Training & Development)

Image-Courtesy-Google

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