Cancer in Companion Animals

Studies show that 1 out of 4 dogs will develop cancer. Although it cannot be prevented, it is important to know the signs to look out for because early detection is key. It is recommended to recognize what your pet’s normal behaviour is in order to identify if anything becomes abnormal quickly.

Signs of cancer include:

  • Unusual lumps/bumps that increase in size
  • Sores that don’t heal (indicates that the immune system is compromised in some way)
  • Decreased weight/appetite lasting more than 24 hours (If Fluffy usually begs for scraps but suddenly seems uninterested or not wanting to eat anything at all)
  • Lethargic/no energy
  • Inability to urinate or defecate

If you notice any of these signs, contact your veterinarian so that further testing (such as blood work, x-rays, biopsies) can be performed in order to confirm or rule out cancer. Once a diagnosis of cancer is confirmed, your veterinarian will go over treatment options. The success of treatment depends on the stage and type of cancer and how well it will respond to treatment.

Treatment options include:

  • Surgery – Involves removing or debulking a tumour.
  • Radiation Therapy – Ionizing radiation used to kill abnormal cells.
  • Immunotherapy – Used to activate the immune system into fighting off the cancer
  • Chemotherapy – Systemic drugs that are used when cancer has spread, or it is not a localized tumour.

With the use of any drugs, there is the possibility of side effects. The side effects of chemotherapy are vomiting, diarrhea, and decreased white blood cells. In regards to the white blood cells, your veterinarian will be closely monitoring those values to see if they get to low. If they do, we will look at decreasing the dose, changing the medication, or putting your pet on an immune-stimulating drug. Hair loss is a less common side effect in animals, but in breeds that continuously grow hair coats like poodles may experience some thinning of the hair. It is also important to note that the drugs will remain active in your pet’s system for a couple of days after treatment. So, it is suggested to have them urinate/defecate in a separate area away from other pets and to wear gloves when picking up after them. It is also recommended to have separate water/food bowls if you have healthy pets in the house to prevent it from affecting them. Also, if you are the one administering the medication to your pet, wear gloves and wash hands after doing so.

Some types of cancer can be cured, while others can only be managed to decrease the spread. If your pet is not responding to treatment or if the cost is an issue, this is where palliative care comes into play. Palliative care is a way to make your pet comfortable and to improve its quality of life without slowing cancer, essentially just treating the clinical signs. You should discuss with your veterinarian what the best palliative care plan is for you and your pet.

Written by: Sabrina