RADIATION THERAPY

Introduction to Radiation Therapy for Pets

Following an MRI to determine the location and size of a tumor, radiation therapy may be recommended as a treatment option for your pet. This form of cancer treatment is often advised when surgical removal of a tumor is not feasible or as a post-surgical measure to reduce the likelihood of the tumor reoccurring. Stereotactic Radiation Therapy (SRT) is a specific type of radiation therapy frequently employed for tumors in the brain, spinal cord, and peripheral nerves. Its advantage lies in its ability to precisely target the tumor while safeguarding the surrounding healthy tissue. SRT has been a long-standing treatment in human medicine, and recent studies confirm its efficacy for animals, often matching or surpassing other radiation therapy methods.

Understanding SRT Treatment For Pets

Stereotactic Radiation Therapy (SRT) for pets is a non-surgical procedure. It’s a painless treatment that doesn’t require an overnight hospital stay. Typically, pets undergo SRT for 3 to 5 consecutive days. During each session, they are anesthetized for their comfort and safety, but most pets tolerate this process well.

Before starting SRT, a CT scan is necessary, even if an MRI has already been performed. This additional scan allows the veterinary team to precisely plan the treatment. A machine called a linear accelerator is used to administer the radiation. The setup for this machine, based on data from both the CT scan and MRI, requires a few days to ensure everything is safe and accurate.

Are There Side Effects?

Most pets receiving SRT experience minimal to no visible side effects, such as skin irritation or hair loss. They may feel drowsy or tired for a week or two following the treatment, but this usually resolves independently. In rare cases, some pets may develop a treatment-related inflammatory reaction a few months post-SRT, but this can generally be managed effectively with medication.

Follow Up Care

Post-treatment, pets will have follow-up appointments with the neurology team. These visits include medication reviews and comprehensive neurological examinations to assess the pet's condition. Typically these visits start one month after treatment, and gradually space out as your pet’s health improves. As always, please check in with the neurology team if you have any concerns about how your pet is doing.

MRI scans are the most effective way to evaluate the tumor's response to SRT, and the veterinarian may recommend periodic MRIs or additional scans if new issues arise.

Understanding the Prognosis After SRT

Although Stereotactic Radiation Therapy (SRT) has a high success rate in improving pet’s quality of life, it's important to remember that no medical treatment offers 100% certainty. In the case of brain tumors, our goal is to shrink the tumor and slow down it’s growth. It is not unusual to see regrowth of the tumor at some point, often more than a year after treatment. Additionally, a small percentage of pets, about 5%, may experience complications where the radiation affects the healthy parts of the brain, spinal cord, or nerves. However, this is relatively rare.

It’s crucial to monitor your pet closely for any symptoms and report them to your veterinarian. These symptoms could be similar to the ones that initially led you to seek neurological consultation, or they might be entirely new. Early detection and communication with your vet are key to addressing any potential issues promptly.