Chemotherapy for Dogs with Cancer

Because cancer is one of the most dangerous diseases that domesticated dogs can contract, dogs with cancer have a very low probability of survival, even with the best treatment. However, if you have a dog that is suffering from cancer, do not give up on your pet just because its chances are slim. There are treatments available for dogs that have cancer that can help to improve the animal’s chances.

What is Cancer?

Canine cancer occurs when a cell or group of cells in the dog’s body go through a set of several specific mutations, which result in the mutated cells continually reproducing themselves, with no way to stop. The mutated cells, called cancer cells, continue to divide and clump together in an ever-growing pile known as a tumor. As of now, the tumor is localized and solidly packed with cancer cells. This type of tumor is called a benign tumor. If a benign tumor mutates even more, it may start to grow root-like tendrils of cancer tissue that penetrate further into the dog’s body. These tendrils can break off and form new tumors in different parts of the body. Cancer in this condition is called malignant.


One of the most popular methods of treating canine cancer is chemotherapy. This treatment consists of intravenously flooding the patient’s bloodstream with toxic chemicals. It works for treating canine cancer because the chemicals are slightly more toxic to cancer cells than healthy cells, so the cancer dies out of the body before the poisons can do any permanent damage.

Using Chemotherapy to Treat Dogs with Cancer

Chemotherapy is most commonly used when the cancer is malignant. This is because the other two methods of treating cancer in dogs, surgery and radiation therapy, are only designed to treat a localized region. Surgery is unsafe when removing large quantities of tissue or when cutting too deep into the body, so it's clearly not to be used to treat cancer that is spreading throughout the body. Radiation therapy can't be used to treat a body-wide malignancy, because it's dangerous to expose the dog’s entire body to such intense radiation. By process of elimination, chemotherapy is determined to be the best treatment for malignant cancer in dogs, because it treats the whole body simultaneously.

When to Avoid Chemotherapy

The toxic chemicals used in chemotherapy always make the patient feel extremely sick and uncomfortable, and it's also a very expensive procedure. It's not advisable to use chemotherapy unless absolutely necessary. Most tumors can be removed using the other two treatment methods, especially if the tumor is benign.

Dogs with malignant cancer usually don't have long to live. While it is unlikely, it is possible to cure a malignant case of canine cancer completely by using chemotherapy; if you have a dog that suffers from cancer, do not give up.