Dog, Health

Cancer In Dogs – The Signs And Symptoms You Should Know

Like its human counterpart, canine cancer can affect many parts of the body including the skin, bones, and internal organs from the brain to the anus. Cancer in dogs also takes many forms in terms of metastatic progress with some growing slowly while others do so rapidly. Effective treatments against cancer have been developed while others are still in their developmental stages although it must be emphasized that early diagnosis is a key to a successful treatment.

Symptoms of Cancer

Since the symptoms of cancer are also similar to other types of canine diseases and disorders, it is important to seek veterinary advice. In this way, the proper diagnosis and corresponding treatment can be administered at the soonest possible time, thus, increasing the likelihood of success in beating cancer.

Nonetheless, the Veterinary Cancer Society has identified the ten most common symptoms of canine cancer, as follows:

• Abnormal swellings on any part of the body that persists despite treatment with antibiotics and even continue to grow

• Skin sores that refuse to subside despite symptomatic treatment with medications

• Unexplained weight loss • Loss of appetite or marked decrease in appetite

• Bleeding and other fluid discharges from any of the body openings like the anus

• Offensive odor even after taking baths • Difficulty in eating or swallowing both solid foods and liquid

• Loss of stamina and energy with marked hesitation to engage in exercise where it was a favorite activity before

• Persistent lameness or stiffness in the limbs

• Difficulty in breathing as well as urinating or defecating

If the dog exhibits more than two of these symptoms even for a short period of time, immediate veterinary attention must be provided.

Causes of cancer

Causes Like human cancer, all types of canine cancer are the result of the uncontrolled growth of abnormal cells in the body. It must be noted that in normal cellular functioning, the cells grow, divide, and then die in a rapid-fire orderly pattern especially during the early years.

However, as the dog ages, the cells will only grow and divide to replace dying cells and to assist in the repair of injuries. But cancer cells do not follow the normal pattern since these continue to grow and divide. And instead of dying like the normal cells, cancer cells will continue to produce more and more of their kind until such time that the normal cells in the surrounding area are overrun.

The root cause of the development of cancer cells can be traced to DNA damage. DNA is the building block of life itself since it is present in every cell with the added information that normal cells can usually repair DNA damage on their own. This is not true with cancer cells.

The damaged DNA can be inherited from a parent. This accounts for the high risks of cancer in dogs with family histories of either parent suffering from cancer. It appears that the DNA undergoes mutation even without outside stressors. Exposure to environmental carcinogens can also damage DNA.

These carcinogens include smoke, pesticides, fertilizers, and other toxins as well as an unhealthy diet. Unfortunately, veterinary science has yet to discover a guaranteed way to prevent cancer from occurring in an otherwise healthy canine body.


The first good news is that there are sophisticated diagnostic tools and techniques to diagnose canine cancer. But it is not only the presence of cancer in the dog that can be determined with finality since the exact location and metastasis stage of cancer can also be detected. Take note that the cancer is named for wherever the cancerous cells were found – anal cancer for the anus, lung cancer for the lungs, and so on and so forth.

These diagnostic tools and techniques are combined to provide for the definitive diagnosis and to guide veterinarians as to the treatment plan. These tools and techniques include imaging technology (like x-rays, ultrasounds, MRI and CAT scans) and biopsy (removal of a piece of the tumor for grading purposes).


Once diagnosis has been made, the treatment protocol must be started as soon as possible since the earlier cancer is treated, the better its prognosis. The treatment protocol will expectedly vary from one dog to the next based on criteria like location, type, and stage of cancer as well as the physical condition of the canine. Discussions with the veterinarian are a must especially as there are tough decisions to be made regarding the treatment. At present, there are three ways by which canine cancer can be treated, by surgery, chemotherapy, and radiation therapy.

Surgery may be necessary to remove the cancerous tumor from the body. This is most applicable to localized cancers with more than its fair share of reservations when cancer has spread to other areas of the body. In the latter case, surgery can only lessen the number of tumors in the body but not necessarily stop the cancer cells from metastasizing.

Chemotherapy is the second choice after surgery. Basically, the chemotherapy drugs are used to kill the cancer cells with the main side effect being that the normal cells are being killed, too. Veterinarians will strive to balance the need to kill as many cancer cells as possible with the need to preserve as many normal cells as possible.

Chemotherapy is usually given intravenously with very few anti-cancer drugs given in oral doses.
Radiation therapy involves killing the cancer cells with radiation beams. It is most successful when the tumor is localized and solitary instead of the cancer cells being spread in other areas.

The Costs

The costs for treatment of canine cancer vary widely depending on factors like location, type, and stage of cancer as well as the combination of treatment methods used. Diagnosis can cost more than $200 while major surgery starts at $1,500 and chemotherapy ranges from $20 to $2,000 per session for 3-6 months of treatment. Radiation therapy is more expensive at $2,000 to $5,000 for the duration of the treatment.

Obviously, when cancer is left untreated, death is at the dog’s doorstep. Canine cancer can also lessen the dog’s ability to fight off a wide range of diseases, thus, the array of health complications.