Page 3332 - Cote clinical veterinary advisor dogs and cats 4th

Consent to Perform Radiation Therapy

VetBooks.ir Patient name:_________________________________
Pet owner’s name:_____________________________ Med rec #____________
Best contact during/after procedure (e.g., cell phone number):____________________

INTRODUCTION FORESEEABLE RISKS TO THE PROCEDURE
We want to make sure that you understand the planned medical There are two types of side effects that occur with radiation therapy:
procedure to be performed on your pet. You should know why the early and late. Early side effects are related to the total amount of
procedure has been suggested, what the potential benefits are for radiation delivered and are more common with definitive protocols
your pet, and the most common/important risks of the procedure. since those use a higher total radiation dose. Late side effects are
Alternatives to this procedure, when applicable, will be discussed related to how much radiation is delivered per dose and are more
with you. It is also important that you recognize that medicine is common with palliative protocols. Side effects also depend on the
not an exact science, and that the outcome cannot be guaranteed. area being irradiated. Hair loss and change in hair color can occur
We encourage you to ask us as many questions as required for in radiation fields, but are fortunately only cosmetic concerns.
you to make a well-informed decision. Early side effects are temporary and common. They usually begin
within 2 weeks of starting radiation therapy and resolve within two
BENEFITS/OPTIMAL OUTCOME OF THE PROCEDURE weeks of finishing. They are usually apparent where the radiation
Radiation therapy is used to treat cancerous and certain non- was administered. Skin in the radiation field can develop moist or dry
cancerous disease processes. Radiation therapy works best on desquamation, akin to a sunburn. Similarly, ulceration of the nasal
microscopic disease, meaning it is most effective when used to cavity, sinuses, or mouth can occur if they are in the radiation field.
treat cancer cells left behind after surgery or other treatment has If radiation is aimed nearby, inflammation of the esophagus (the part
removed the bulk of a tumor. In such a setting, the goal of radiation of the throat that connects the mouth to the stomach) can cause
therapy is to kill cancer cells left behind to reduce the risk of tumor regurgitation or inflammation of the trachea (windpipe) can cause
regrowth. Radiation therapy can also be used to shrink tumors or coughing. Colitis, or inflammation of the colon, can occur when the
reduce pain when surgery is not possible. hind end is irradiated and can cause diarrhea. Early side effects are
treated with pain medication, antibiotics, and other supportive care
EXPLANATION OF THE PROCEDURE as needed until they resolve.
Radiation therapy involves delivery of x-rays to a specific part of Late side effects occur 6 months or more after radiation therapy.
your pet’s body, targeting cancer cells while sparing normal healthy These side effects are permanent, but they are not common. They
tissues. These are the same as x-rays used for imaging (for example, can include bone necrosis (die-off of bone tissue), cataract formation
to identify broken bones), but have higher energy. Your pet must in the eyes, blindness, or nerve damage. If the gastrointestinal tract is
hold very still during this procedure, so he or she put under light affected, small areas of scarring and narrowing called strictures can
anesthesia for a short period of time, usually around 15 minutes. occur. In less than 5% of patients, a different cancer develops at the
Short-acting anesthetics are used so that your pet will be alert and radiation site. For these reasons, radiation therapy may sometimes
wake up quickly after the procedure. be avoided in young patients or patients who are expected to live
There are two types of radiation therapy protocols used: definitive for many more years.
and palliative (also called “hypofractionated”). Palliative radiation
is not given with the intent to cure cancer, but rather to improve Other anticipated risks specific to your pet:___________________
the quality of life for the pet by reducing tumor size or extent.
Depending on the type of protocol developed for your pet, this will _________________________________________________________
be performed daily Monday-Friday for several weeks (definitive), or
for only a few treatments (palliative; for example, once weekly for
4 weeks). ALTERNATIVES TO THE PROCEDURE
Additional procedures planned for your pet at the same time Alternatives to radiation therapy depend on the type and location of
as the radiation therapy: disease being treated, but may include surgery, chemotherapy, or
supportive care. Selecting a different form of treatment may result
____________________________________________________________ in increased risk of tumor regrowth, spread, or shortened survival
time. Other alternatives for pets with cancer include euthanasia or
USE OF SEDATIVES OR ANESTHESIA hospice care.
General anesthesia causes your pet temporarily to become
unconscious. Although anesthesia is performed routinely with good AUTHORIZATION
outcomes, it does bring risks, including a very small risk of death. By signing this form below, you agree that:
These risks are increased for animals with severe disease. To reduce • You understand how/why the procedure is likely to help your
these risks, your animal will be supplied with extra oxygen, and will pet
be monitored closely during both anesthesia and during recovery • You understand what will be done to your pet during the
from anesthesia. The decision to perform this procedure is based procedure
on having assessed that the anticipated benefit is greater than the • You understand the known risks that accompany the procedure,
anesthetic risk. and also understand that unforeseen complications may occur

From Cohn and Côté: Clinical Veterinary Advisor, 4th edition. Copyright © 2020 by Elsevier Inc. All rights reserved.