The lifespan of a dog with cancer can vary depending on various factors such as the type of cancer, the stage at which it was diagnosed, the age and overall health of the dog, and the treatment options available.

Some cancers such as lymphoma or leukemia can be very responsive to treatment, and with appropriate care, a dog with these cancers can live several months to a few years. Other types of cancer such as osteosarcoma or hemangiosarcoma can be more aggressive, and even with treatment, the prognosis can be poor.

In general, early detection and treatment are important for improving a dog’s chances of survival. Additionally, supportive care such as pain management, nutritional support, and quality of life measures can also play a role in improving a dog’s overall health and wellbeing.

It is important to work closely with a veterinarian to determine the best course of action for a dog with cancer and to monitor their condition closely throughout their treatment.

Man and dog lying in grass

Cancer treatments for dogs

Traditionally, cancer in dogs is treated similarly to cancer in humans, with three basic types of treatment: surgery, chemotherapy, and radiotherapy. Newer therapies are also being introduced into the animal world, including immunotherapy & CBD oil for dogs with cancer.

Surgery

Surgery is most often used in cases where veterinary surgeons believe the procedure has a good chance over removing most or all of a cancer. Therefore, surgery is often recommended for tumors in the skin, or for distinct growths. Surgery is also used to relieve pressure caused by tumors, which may be contributing to negative side effects and discomfort.

Chemotherapy

Chemotherapy is a widespread treatment, used in treating both isolated cancers and those that have spread. Chemotherapy is sometimes used as a primary mode of treatment, but it’s also used as a supplement to surgeries. Chemotherapy for dogs usually has fewer side effects than chemo for humans, as dosages are often smaller. In the majority of cases, chemotherapy is not expected to cure cancer. Instead, it is used to slow progression and symptoms.

Radiotherapy

Radiotherapy refers to the use of X-rays targeted at cancer cells in order to destroy them. Like chemotherapy, radiotherapy might be recommended by vets as an alternative to surgery (if surgery proves difficult or impossible). Radiotherapy is most often seen as a curative treatment and is often the first choice for cancers, where it offers the best chance of long-term tumor control.

Immunotherapy

Immunotherapies work on the basis of supporting the body’s own immune system. As a relatively new form of cancer treatment, it’s shown success in both humans and dogs. Penn Vet from UPenn describes a number of different immunotherapy treatments for dogs, such as a bacterial vaccine, which enhances the immune system’s ability to fight spreading cancer, as well as creating a long term “memory” response.

Isolated tumors & cancer that has not spread

When dogs are diagnosed with an isolated tumor, surgery is common. Veterinary surgeons will seek to remove the cause of cancer, and may follow up with courses chemotherapy or radiotherapy. How viable and successful surgery will be depends a lot on where the tumor is growing. If the growth is in the brain, for example, surgery might not be possible.

How long can a dog live after being diagnosed with this kind of cancer? For dogs who successfully recover from surgery, there really is no limit on how life or well they can live. Dogs who undergo surgery to remove lumps and tumors have often been diagnosed at an early stage, meaning that they often remain cancer-free after treatment for the rest of their lives.

(Although there is some evidence that dogs who develop a tumor are more vulnerable to developing tumors at a later date).

Cancer that has spread within the body

Treatment options, life expectancy, and a dog’s quality of life all depend on how, where, and when cancer spreads. In a minority of cases, such as very old dogs, vets may also recommend palliative care and eventually euthanasia. But even if your dog is diagnosed with terminal cancer, there are plenty of options to ensure a happy daily life. Here’s some info on three of the most common cancers in dogs:

Skin cancers—Mast cell and Melanoma

Dogs often develop lumps under their skin. Some of these are benign, while others develop into cancer—mast cell and melanoma being two of the more common types. Mast cells are found in connective tissues, which exist in the muscles, vessels, and nerves under the surface of the skin, which can develop into cancerous cells. Melanoma is a similar form of cancer and the most common kind of oral cancer in dogs.

How long can a dog live after being diagnosed with this kind of cancer?  According to FetchVets, while skin tumors are among the most common tumors found in dogs, many are benign. However, skin cancers that continually recur in the same place may be more dangerous, as they can spread to other sites without being detected. Biopsies are helpful in this case to determine how aggressive tumors are.

Leukemia or Lymphoma

Lymphomas are cancers of the white blood cells. Because white blood cells circulate in the blood as well as the lymphatic system, lymphoma can cause a cancer that’s fast-spreading and difficult to remove. According to PetMD, dogs can develop several different forms of lymphoma, with the most common symptom being enlarged or hardened lymph nodes, especially in the throat area.

How long can a dog live after being diagnosed with this kind of cancer? Because lymphoma is often widespread, surgery is often unable to remove all traces of cancer. Chemotherapy is a common treatment to help slow the spread of the disease—as left untreated, the average life expectancy for dogs after diagnosis under three months. Unfortunately, some dogs diagnosed with lymphomas will not respond to treatment, and so it’s important for owners to engage in open and empathetic conversations with vets.

Sarcomas

VCA Hospitals defines sarcomas as a broad category of tumors arising in connective tissue, muscle, nervous tissues, or bones in dogs. Abnormal and accelerated production of cells is the usual cause of sarcomas such as fibrosarcoma.

Fibrosarcomas are tumors that develop from fibroblasts, which are the most common cells of the connective tissue in the body. Because of this, Fibrosarcomas often occur in the connective tissues beneath the skin.

Osteosarcoma is the most common type of bone tumor in dogs. It arise when cells overproduce and begin to break down bone, and normally affects the longer bones in a dog, such as their legs. As such, these types of sarcoma are more common to large dog breeds, such as Great Danes. In fact, Great Danes are thought to be 200 times more likely to develop osteosarcomas than toy breeds.

How long can a dog live after being diagnosed with this kind of cancer?

Life expectancies vary again, especially in terms of where the sarcoma is located. Fibrosarcomas can be highly treatable, thanks to their location near the skin. Unfortunately, osteosarcomas tend to be more aggressive and faster spreading. Prognosis after surgery is an average of five months, although that figure rises to a year when chemotherapy is also prescribed.