Oak Park Pet Owners: How to Recognize the Signs of Cancer in Your Pet


Pet parents have some options to consider when the vet says their pet has cancer. You need to understand the type of cancer your pet has, what the treatments are, and the prognosis you and your pet are facing together.

Some of the significant signs of cancer in pets include masses along the jaw or tooth line, paleness or yellowing of the skin, oozing of blood from the mouth, or persistent sores. If you see anything in your pet that is questionable or abnormal, you need to contact your veterinarian immediately. 

signs of cancer in pets

While cancer is more widespread in dogs than cats, cats can also get cancer. Many different types of cancer can occur in cats and dogs. Read below to find out the common signs of cancer in your pet.

Symptoms And Signs of Cancer In Dogs and Cats

Cancer can be challenging to detect in dogs and cats because the symptoms are similar to other illnesses that could be present, which is why yearly or twice yearly physical exams are so important. Middle-age or older pets are more at risk. The following are symptoms of cancer in dogs and cats.

  • Increased thirst
  • Increased urination
  • Vomiting
  • Changes in stool
  • Respiratory changes
  • Rapid weight loss
  • Loss of appetite
  • No interest in playing or exercising
  • Organ enlargement
  • Masses along jaw or tooth line
  • Oozing of blood from mouth or rectum
  • Persistent sores
  • Poor coat quality
  • Constipation
  • Paleness or yellowing of the mucous tissues or skin
  • Abnormal odors
  • Changes in oral health
  • Nosebleeds

If a dog or a cat develops any of these symptoms, it could signify cancer. You must get them to the veterinarian as soon as possible.

What Are the Common Forms of Cancer in Cats and Dogs

Cancerous tumors are masses of tissue caused by cells dividing too quickly or do not die when they should. Tumors can develop from any tissue type and can be found in many different locations. The following information includes what types of cancers are most common in dogs and cats:

What Are the Most Frequent Cancers in Dogs?

Cancer is a scary diagnosis for any pet parent. With help from your veterinarian or a team of veterinarians, your pup will receive the best treatment possible. Below are the most common cancers found in dogs.

Malignant Lymphoma

Lymphoma is a type of cancer that affects the lymphatic system. Most dogs will have enlarged the lymph nodes (see video)  in one or more parts of the body. It harms the dog’s immunity. Lymphoma may result in changes in the eyes and internal organs. Specifically made chemotherapy protocols treat lymphoma.

It involves weekly sessions of chemo administration at first, then visits every other week for about six months. Many pups go into remission due to therapy and have a good quality of life for longer.

Lymphomas can vary in their aggressiveness. The prognosis depends upon the stage of your dog’s cancer at the time of treatment and what type of treatment they receive.


This type of cancer occurs in the bone. It is an aggressive type of cancer that spreads rapidly, especially to the lungs, lymph nodes, and other bones. The treatment typically involves the amputation of the affected bone and chemotherapy. Radiation therapy is another treatment that may be added to treatment.

Unfortunately, most dogs only live for about two or three years, even with the best treatment. With this type of cancer, it can likely come back.

Mast Cell Tumors

This type of cancer mainly occurs as a skin lump. Malignant mast cell tumors can migrate to the lymph nodes, spleen, liver, and bone marrow. Treatment may include surgery, chemotherapy, and radiation, which is contingent on the grade and stage of the tumor.

Fortunately, mast cell tumors are one of the most treatable forms of cancer in dogs. Your vet will remove the tumor. The prognosis typically depends on the grade of the tumor. For low-grade tumors that do not spread, the prognosis is generally excellent.


This type of malignancy can affect any part of the body but usually occurs in the dogs’ oral cavity. Melanomas look like darkly pigmented growths, but they may also be pink in color.

If you find an unusual growth in your dog’s mouth, it is essential to get to the vet as soon as possible, as melanoma can spread to other parts of the body.

The treatment of melanoma typically includes surgery to eradicate the tumor. Chemotherapy or radiation is the general course of treatment. Some dogs who have had a melanoma may be eligible to receive a vaccine to prevent a recurrence.

As long as melanoma does not spread to other places in the body, the prognosis is good. If it has spread, the prognosis is poor. The melanomas need to be surgically removed before metastasis for the assurance of a good outcome.

What Are the Common Cancers in Cats?

You want your cat to live a healthy life for as long as possible. Cancer does not have to be a death sentence for your feline companion. If it is uncovered and treated early on, the prognosis will likely be good. Make sure if you see anything unusual in your cat, you contact your veterinarian right away.

The following are the most frequent types of cancer in cats:


Lymphoma occurs when a cell of the immune system becomes cancerous and affects multiple parts of the body. There is a definite correlation between lymphoma and feline leukemia. The classification of feline lymphoma is often split into several groups. These include:

  • Multicentric – Various organs involved
  • Gastrointestinal – Digestive
  • Mediastinal – Lymph nodes and chest
  • Renal – Kidney
  • Spinal – Brain or spinal cord
  • Nasal – Sinus

Multicentric, nasal, and gastrointestinal forms of cancer occur more in middle-aged cats and are not typically associated with the feline leukemia virus. Mediastinal and spinal forms of cancer typically affect younger cats of age 2 or 3, and they are associated with the feline leukemia virus. Cats with kidney form of cancer may be positive for feline leukemia, and they average around eight years of age.

Treatment for lymphoma in cats is usually a combination of chemotherapy and various medications. With nasal lymphoma, radiation therapy is another course of treatment that is advised for this condition.

Squamous Cell Carcinoma

This type of cancer is the equivalent of skin tumors in fair-skinned people. Cats are affected in the tips of the ears, the nasal area, and the eyelids. The affected regions may appear pink in color on the skin with some scaling.

If your cat has this type of cancer, the vet will most likely recommend that they stay out of the sun and that you apply water-based sunscreen on them where they are affected. If the condition worsens, the skin may have growths and have ulcerated wounds that can bleed.

If it goes untreated, cancer can spread to the lymph nodes or lung tissue. Treatment for this kind of cancer is the surgical removal of the tumor. Radiation therapy, cryotherapy, laser, and photodynamic therapies are all treatment options.

Soft Tissue Sarcomas

Soft tissue sarcomas in cats are rare, but they can appear in injection sites from a vaccination. This type of tumor develops in the connective tissues of cats. Although they can occur anywhere on the cat’s body, they commonly occur on the skin or subcutaneously. Surgery is part of the treatment for injection site sarcoma. Radiation and chemotherapy are also recommended.

This type of cancer is challenging to treat. It depends on where on the body it is and how quickly it is treated. Cats who have a tumor on the legs can have an amputation performed. However, cats with cancer on the body’s trunk do not have as good of a prognosis. Regrowth is also a possibility.

Mammary Gland Carcinomas

Mammary cancers are most commonly diagnosed in elder cats between 10 and 14 years old. This type of cancer is very aggressive, and 80 to 90 percent of tumors tend to be malignant. Mammary tumors often spread to the adjacent tissues. They may also metastasize to distant sites. Something called a radical mastectomy may be performed, possibly followed by chemotherapy.

The prognosis for mammary gland carcinomas depends on the size of the tumor and the grade of cancer. Cats that have tumors that are more than 3 centimeters in size typically have a survival time of about six months, while cats who have tumors less than 2 centimeters in size could live for another three years after surgery.

Cats will experience cancer symptoms in varying amounts, with a period that is different for each cat. The above are all average times, ages, and occurrences that come with these types of cancer. The individual symptoms of these illnesses do not always indicate cancer. Always rely on your veterinarian for the proper diagnosis.

How Can I Support My Dog or Cat With Cancer?

Cancer is a painful condition for humans, as well as animals. Your cat or dog needs their rest, even more, when they are sick.

Every moment you spend with your dog or cat is precious. You can also comfort them by being there to hold them and give them lots of love during this difficult time.

Keep an Eye Out for Common Signs of Cancer in Pets

Cancer is a serious diagnosis, but it does not have to be an immediate death sentence. If the cancer is discovered early enough, your pet will likely have a good prognosis.