What is cancer?

In its simplest form cancer is a group of abnormal cells. These cells often form in a large mass called a tumor. Cancer cells are constantly growing and reproducing. Cancer cells which are not dangerous are called benign. Cancer cells which attack organs or other cells are called malignant.

How many types of cancers are there?

There are more than 100 types of known cancers. They are named by the type of organ or cell where they develop. Some of the most common cancers are breast cancer, skin cancer, mouth cancer, bone cancer and tissue cancers such as connective tissue cancer and lymphatic tissue cancer.

How does cancer start?

Cancer starts with a healthy cell that transforms. The transformation process begins with initiation. Healthy cells divide and reproduce continuously. Sometimes a healthy cell will divide incorrectly and produce a mistake that will mutate. The next step is called promotion. Promotion requires agents to stimulate the mutated cell to grow and reproduce into cancer. Common promoting agents are environmental factors and drugs.

What dogs are prone to cancer?

Cancer is visible in all breeds of dogs. However some breeds of dogs are more likely to develop certain cancers based on genetic factors. The three dog breeds most likely to develop cancer are Bernese Mountain Dogs, Boxers and Golden Retrieves. Older dogs are also more susceptible to cancer.

Symptoms of Cancer

Because there are so many forms of cancer there are many possible symptoms of cancer. Some symptoms include growing or changing lumps, cuts or sores that do not heal, swollen lymph nodes, unexplained bleeding, difficulty breathing, sudden loss of weight, decreased physical activity or stamina, recurring vomiting or diarrhea, sudden abdominal swelling and signs of physical discomfort. These symptoms are not exclusive to a cancer diagnosis, but should be evaluated by a veterinarian.

Diagnosis of Cancer

There are many ways in which your veterinarian may diagnose cancer. Some of these are blood tests, x-rays, ultrasounds, biopsies and laparoscopy. Once your veterinarian has diagnosed your dog with cancer you might want to seek a second opinion and the advice of a veterinary oncologist. For most people a diagnosis of cancer seems like the end of the world. While it is a bitter pill to swallow, it is not a death sentence. If caught early there are many treatment options available.

Treatments for Cancer

Depending on the location and severity of the cancer your veterinarian may suggest one or more the following treatments.

Surgery – Surgery is the oldest cancer treatment. Surgery is usually recommended for cancers that have not spread and are easily accessible. The goal with surgery is to remove all or most of the tumor and in some cases the normal tissue surrounding the tumor. While surgery is effective on localized tumors it can have many complications. Some common complications are infection, bleeding, pain, loss of normal function, and possible recurrence of the cancer.

Radiation – Radiation is the use of x-ray like energy to destroy the cancer cells. The concentrated beam either kills or damages the cancer cells making them unable to reproduce. Radiation is not always a treatment option due to the size and location of the tumors. Possible complications from radiation therapy are damage to normal tissue and lowered immunity. Anesthesia is required to perform radiation.

Chemotherapy – Chemotherapy is using drugs to kill or destroy the cancer cells. This process is usually used to shrink or stop the growth of the cancer cells. Chemotherapy drugs are either delivered by pill, intravenous injection, intramuscular injection or subcutaneous injection. Chemotherapy is usually unable to cure cancer on its own and is commonly used in conjunction with surgery or radiation. Common side effects from chemotherapy are nausea, bleeding, lowered immunity and occasionally hair loss.

Cryotherapy – Cryotherapy freezes cancerous tissue with probes. This treatment is used infrequently and can destroy cancer cells with limited damage to the surrounding tissue. This therapy is only available for limited cancers based on severity and location.

Hyperthermy – Hyperthermy is the opposite of Cryotherapy since it uses heat probes to destroy the cancer cells. This treatment is also used infrequently and is only available for a limited number of cancers based on severity and location.

Diet – While diet cannot cure cancer alone, it can greatly help to inhibit the growth potential of cancer. Cancer cells feed off of carbohydrates, so the idea here is to limit carbohydrates and increase quality protein. By limiting sugars and complex carbohydrates you can “starve” the cancer cells and help the normal cells stay healthy. It is also recommended to increase quality fats like omega 3 fatty acids.

Nutraceuticals – Depending on the type of cancer your vet may recommend adding nutraceuticals or specialized vitamin supplements to your dog's diet. These supplements can greatly increase function of damaged organs and promote healing. Please consult your veterinarian before adding supplements and herbs to your dog’s treatment plan.

Preventing Cancer

There is no magic formula to prevent cancer in your dog, however being aware of your dog’s environment and what they eat can play a large part. Avoid the use of insecticides, pesticides and herbicides in your yard. Be careful about the products used to clean your floors. Read the labels and avoid cleaners with harsh chemicals. Avoid prolonged exposure to the sun and second hand smoke. Feed your dog quality food without chemicals and preservatives. Keeping regular veterinary well exams to monitor changes in your dog’s health can also make a difference. It is also important to research your dog’s breed and family history to know if they are predisposed to certain cancers.