Principles of Cancer Surgery in Dogs and Cats
- Surgical removal of localized cancer can often be curative if the cancer was detected at its earliest stages, prior to spreading to other parts of the body.
- Surgeons will often play a critical role in managing your pet's cancer whether it is for obtaining a biopsy sample, performing curative surgery, or alleviating symptoms caused by the tumor.
- Cancer is sometimes referred to as the disease of the elderly since its incidence dramatically increases with age. Some veterinarians may not feel comfortable performing an aggressive surgery on an older pet because of concerns whether the pet will withstand the surgical intervention. However, no pet should be denied treatment on the basis of age.
- An older pet may be in better health than a 4 year old pet, thus the question of compatibility with surgery should be discussed in terms of the pet's overall health and likelihood of benefiting.
- Surgery is the mainstay of cancer management but it is not always necessary. Pet owners should engage in a detailed discussion with their veterinarian and veterinary oncologist to ensure that all questions have been answered and a logical conclusion about the necessity of a surgery was reached.
Questions to ask before the surgery:
- Prior to scheduling a surgery for your pet, the following questions should be answered by both your pet's medical team and your family.
1. What is the type, stage, and grade of cancer to be treated?
2. What are the expected effects of your pet's particular tumor?
3. Is cure or significant health improvement achievable without dramatically compromising your pet's quality of life?
4. Is surgery necessary or are there alternative, less invasive treatments available?
5. What is expected in terms of post-operative care?
6. Can your family handle taking care of your pet's post-operative needs? If your pet will require 24/7 care for the first few days, can you take days off from work for the required period of time or have the resources to leave your pet in the hospital for medical supervision?
Types of surgery
- The type of surgery that will be performed on your pet will largely depend on the anatomical site of the tumor and the type, size and stage of the tumor.
- It can either be performed as a single treatment or in combination with chemotherapy or radiation to enhance the overall chance for cure.
Surgery for cure:
- This type of surgery will attempt to remove all traces of cancer from your pet's body. It is generally believed that the first surgery has the best chance of cure. The surgeon will not only remove the tumor itself but also some of the surrounding tissues to make sure that no cancer cells are left behind.
Lymph node removal:
- Lymph nodes are structures that drain lymphatic fluid for circulation into the lymphatic system and is one of the mechanisms by which tumor cells can spread to other organs.
- In some cases, when the tumor cells were found to spread to the nearby lymph nodes, it is desirable to remove the lymph nodes to prevent further spread of tumor cells.
- However, there is still some controversy as to when such procedure should be performed. Generally speaking, lymph nodes should be removed if they are positive for cancer cells.
- This type of surgery is not aimed to cure the pet but rather improve the pet's quality of life by alleviating some of the painful symptoms associated with the presence of cancer.
- It should be carefully considered how the procedure's expected risks compare with expected benefit.
- If the surgical treatment will result in worse outcome than no treatment at all, other methods
of palliative care should be applied such as pain management.
- This type of surgery refers to the incomplete removal of a tumor. It is usually performed to enhance the efficacy of other types of treatment such as cryosurgery or radiation.
Miscellaneous surgical intervention in cancer management:
- Surgeons may also use their expertise in placing long term vascular access catheters for delivering fluids, chemotherapy or anesthesia and pain relief agents, placing of feeding tubes or performing emergency based operations arising from infections, bowel obstruction, bleeding or intractable pain.
- Some types of cancer in pets can be prevented by surgical intervention. For example, there is evidence that spaying female dogs and neutering male dogs will reduce the risk of breast cancer and prostate/testicular cancer, respectively.
- The removal of precancerous lesions from the skin of white cats or removal of adenomatous polyps from the rectum of dogs may also prevent subsequent cancer development