Palliative radiation therapy

     One of the things that I have come to realize as a radiation oncologist is that palliative treatment is a large part of what we do for animals.  As a veterinarian who is trained to treat cancer, our tendency is usually to want to try to cure our patients.  For this we often recommend aggressive surgery, definitive radiation and/or chemotherapy to try to beat back our patient’s cancer as much as possible.  But when I looked back over the majority of patients that I treat I realized that about 65% of these patients were treated with palliative radiation.  By palliative radiation I mean using a small number of treatments with a large dose each time.  The goals of this type of treatment are to cause as little effects on the patient as possible with as little impact on their quality of life, while trying to either shrink or slow down their tumor or in many cases just providing pain control.  However, palliative radiation very rarely is enough to control the tumor for a significant period of time.  Many times owners elect this course of treatment because they just want to try to keep their pet comfortable and they do not want to go through the side effects that you can get with definitive treatments.  Some cannot afford to go through a definitive treatment course.  Definitive surgery, radiation and chemotherapy can be unaffordable for some pet owners. 

      Palliative radiation can help decrease pain in dogs with bone tumors, or any tumor involving the bone.  If animals cannot eat because of a tumor in the mouth palliative radiation may make it possible for them to eat for a period of time.  Tumors that are ulcerated and bleeding will often dry up with palliative radiation.  When owners cannot afford a definitive course of treatment, palliative radiation may help slow down progression of their pets tumor.  What I have found in treating so many pets with palliative radiation is that many pet owners tell me that they are so happy that the treatment was able to keep their animal comfortable for a period of time, without a lot of side effects.  What this has made me realize is that palliative treatment for animals is just as important, if not more important than trying to cure tumors because in the long run, keeping our animals comfortable for as long as we can is the most important goal.

 

Dr. John Farrelly

Using technology to improve radiation treatment for animals

     As a radiation oncologist one of the tumors that I have disliked treating the most are nasal tumors in dogs.  Nasal tumors usually fill up one or both sides of the entire nasal cavity and sinuses.  In a dog’s head this means that the tumor is basically wrapping around the eyes and the brain and the tumor sits right above the mouth.  So when we treat these patients we usually have to include a great deal of the mouth the eyes and the brain.  In some dogs, treating these areas causes severe short-term side effects, and animals are usually very painful during and for a few weeks after radiation.  We have much better pain medications so it is possible to get these patients through their treatment, but for many pet owners and their animals treating a nasal tumor is a difficult decision and I feel that a lot of dogs were not treated because of these side effects. 

     With the advent of newer radiation technologies this has changed.  Intensity Modulated Radiation Therapy (IMRT) is a newer radiation technique that is becoming available to treat difficult tumors like nasal tumors.   With IMRT the patient is positioned in a positioning device so that their head is very still, and a CT scan is done not only to identify exactly where the tumor is, but also this CT scan is used by a three-dimensional treatment planning computer.  Radiation beams are aimed at the tumor from a number of different directions so that the radiation can approach from all sides. Then the radiation oncologist tells the computer what dose they want to give to the tumor as well as the maximum dose they want to give to the important normal tissues.  Then the computer figures out how to accomplish this.  For each field, small leaves up in the head of the radiation machine are used to deliver different doses of radiation to different parts of the field.  For example, if one of the fields is pointed at the tumor and the brain, the field might give little or no radiation to the brain while at the same time giving a high dose to the tumor.

     For dogs with nasal tumors this means that the radiation can be directed to the tumor and the dose to the normal tissues is minimal.  Dogs that are being treated with IMRT usually have small areas of redness and irritation in their mouths, but most of their mouths, eyes etc. have little to no significant side effects.  This means dogs are much more comfortable going through treatment, but also it most likely will decrease the number of permanent side effects, making radiation much safer.

 

 

Dr. John Farrelly

Sometimes the “where” matters.

When scientists write about themselves, others or our profession, the topics are often about the “whats”. What we do, what topics or areas of interest do we have, or what we produce in terms of research. However, sometimes, the “where” is the most important question.

 I recently had the fortune to travel to Tanzania to witness the Great Migration of wildebeest and other grazing herbivores across the Serengeti. It is truly one of the greatest spectacles in the natural world, being the largest land mammal migration on Earth. There are over one-and-a-half million wildebeest, about 200,000 zebra and 500,000 Thomson's gazelle in the herd.

 Millions of wild animals surrounded me and it was not only a visual spectacle but an auditory one as well. As I closed my eyes, I heard thousands upon thousands of baby wildebeest and zebra calling to their mothers and an equal number of mothers returning the call. The sound was almost deafening.

 This experience took me outside of my day-to-day life and myself. I am one of the lucky few that loves their job and truly, I have never worked a day in my life. Nevertheless, to experience the Great Migration, not just see it on television, but to truly be there, was a life affirming and life changing experience.

 
The most important words I have ever read about this wonderful phenomenon did not come from Science, Nature or for that matter any other respected scientific journal. The words that matter most, were written on an old T-shirt that our driver wore—“The Serengeti Shall Never Die”.

Dr. Gerald Post

“What does a Clinical Trial Coordinator do?”

While this blog may not be the most exciting, there are many more exciting blogs to come about clinical trials, our clinical trial patient success stories and interesting things happening in the comparative oncology arena! Comparative oncology?? If that’s what you’re thinking right now…. Here’s a fun homework assignment: search the internet (or Google “Dr. Gerald Post”)and then leave a comment on what you understood it to be. Anyone that comments regarding “comparative oncology” will receive a free gift from The VCC!  If that’s too much work and you hate free gifts, you can be in suspense until a future blog when I discuss it! J

Back to the “What does a Clinical Trial Coordinator do?” question. Who knows? Maybe someone out there will decide this is what they want to do! My job is to manage our clinical trials from start to finish. This process begins with informing our area veterinarians that a new trial is open and which types of cancers and patients are eligible (mailings, faxes, emails and calls). Once that happens, calls and emails come in from around the country (even Mexico!) to inquire about pet eligibility. 

Working closely with the doctors at The VCC, we determine which patients might benefit from the study and we begin a screening and enrollment process. If a patient passes all screening tests, they are officially enrolled. Many studies even pay for those screening tests to be done on the patient. Once a patient is enrolled, it is my job to oversee all of the study drug administrations, accurate documentation (very important when a drug is trying to get approved), side effects, lab work, ensuring that the protocol is strictly followed, close communications with ACI (Animal Clinical Investigations), VCC oncologists, and the pet owner. 

Each individual patient is monitored closely and if necessary, for the well-being of the patient, he/she may be withdrawn by our oncologist, by the study sponsor or by the owner at any time. While we are all serious about the data that we gather from the trials, our first priority is always the health and well-being of each patient. We will never compromise on what is best for our patients, so no need to worry about these beloved pets being “guinea pigs” or “lab rats”! We treat each patient as if it was our own family member and that never changes – clinical trial or not! There you have it. 

That’s the broad overview of what a Clinical Trial Coordinator at The VCC does. The truth is, it’s so much more and I hope you’re starting to catch a glimpse of why I love my job! As an example, my next blog will highlight a clinical trial patient from a few years ago. Even after Kobi passed away, his family was very excited to write a “Success Story” about his journey through a clinical trial. Check back soon for that story!

 

Maria Salas

Radiation Side Effects

In a previous blog I mentioned how we use technology to minimize side effects to our pets when treating them with radiation.  However, there are many situations where we cannot or do not want to completely avoid normal tissues.  Almost all tumors have microscopic cells that extend into the surrounding normal tissues.  We often use the analogy of an octopus to describe a cancerous tumor.  The body of the octopus is the part of the tumor that we can see either with our eyes, or by some imaging (such as ultrasound, CT scan, MRI etc.).  If we just needed to treat this cancer would be easy to cure with surgery.  The cancer cells that extend into the normal tissue, like the arms of an octopus, often cannot be removed with surgery and these are often what we are treating with radiation or chemotherapy.  When we treat these cells we usually have to treat the normal tissues that they are invading into and this results in side effects in the normal tissues.

Radiation side effects in animals can be severe in some cases, but we are able to manage them, to get pets through treatment.  They usually start around the middle of a course of radiation, but they can get worse for up to a week after treatment is finished.  When the skin, the lining of the mouth, the eye or the colon is treated these side effects usually include redness and irritation of the area.  This looks a lot like a sunburn.  It starts as mild redness and itch, but usually gets worse until the area is very red and/or ulcerated.  When this happens pets usually need pain medications, anti-inflammatories and antibiotics to help keep the animal comfortable.  Fortunately we have many more pain options available for dogs and cats to help get them through this time.  The area is usually itchy so it is also very important that animals not be allowed to lick or chew at the area, so sometimes they need to wear a cone type collar to prevent this.

Fortunately for cats the short-term side effects are usually much less severe than in people or dogs.  Most cats who are treated with radiation usually just get dry, flaky skin or mild redness in the radiation area and they usually are not very painful.

Long-term side effects from radiation usually do not cause problems, things such as changes in hair coat color or thin skin.  Fortunately dangerous long-term side effects, such as bone destruction or radiation induced tumors, are typically very rare and can take many years to develop.

Although side effects from radiation can cause significant pain and discomfort, the radiation protocols that we use to treat animals are designed to try to minimize these effects so that we can get pets through treatment with as little discomfort as possible.

 

 

Dr. John Farrelly

New Technology for diagnosing and treating cancer in our pets.

We see technological advances around us every day.  Things that we couldn’t even imagine ten years ago are happening every day.  I am going to reveal my age here, but when I first started working with computers the text was green on a black background and graphics were cursor-sized boxes.  Today you might be looking at this blog on a smartphone while walking through the park.  Hopefully we use these changes in technology to make our lives better. 

 When it comes to caring for our pets the same is true and it is making a huge difference in the care that is available to our pets.  Today Computed Tomography or CT and MRI are available in many different centers.  PET scans (Positron Emission Tomography) These tools allow us to get an incredibly detailed look inside the body to identify diseases.  When it comes to cancer this is crucial to help diagnose tumors and to identify exactly where the tumor is in relation to the normal tissues.

However, this technology is not just useful for diagnosis.  New advances in technology are changing the ways that we have available to treat tumors.  There are approximately 70 centers in the world that have radiation therapy capabilities for treating animals.  Most of these facilities have linear accelerators for treating cancer, which allow us to focus radiation to the tumor, while avoiding the normal tissues.  Some of these facilities have a technology called intensity modulated radiation therapy (IMRT) or stereotactic radiation.  These techniques, used with advanced imaging techniques, allow us to truly pinpoint the radiation to the tumor, and minimize the dose of radiation to any normal tissues in the area.  By doing this we are able to effectively treat our pets with cancer, while making sure not to damage their normal tissues…helping us achieve our goal of effectively treating cancer, while keeping our pet’s quality of life as normal as possible.

 

I look forward to seeing what the next ten years brings to allow us to provide the best care possible for our pets.

Dr. John Farrelly

“Sammy-a simple story”

Sammy is a 9 year old Golden Retriever whose story is so simple yet so revealing that I needed to share it with you.

 

Sammy had no prior medical problems before being brought into the emergency service of one of our partner hospitals for a severely swollen left rear leg. On the initial examination, the leg was swollen from the tip of the toes all the way up to the hip. The swelling was among the most severe cases I had ever seen.  There was no history of trauma, no chance the dog was hit by a car, motorcycle or even bicycle.

 

Physical examination revealed no evidence of a fracture, insect bite, snake bite or anything else—just severe, severe swelling.

 

Unfortunately, as in many cases these days, finances were a big concern for the owner and she was considering having Sammy humanely euthanized. Our criticalist decided to try and convince her to see if –by chance—one fine needle aspirate of this swelling would give us the information we needed in order to save Sammy. Luckily the owner said “yes.” After checking the entire leg, a small area that was very slightly firmer than the rest of the leg was found. A fine needle aspirate was performed.

 

The aspirate revealed mast cells on cytology. The owner was devastated to learn that here beloved dog had cancer and again, she was considering euthanasia. But yet again, luck smiled on this very special dog. I convinced her to try one week of prednisone-before she made that final decision. By the following week, Sammy was a new dog. The swelling in his left rear leg had completely resolved—except for an area the size of a quarter right near his knee (stifle).

 

Because Sammy was now doing well, enjoying life and the massive swelling had changed to a small mass, the owner elected to have the mass removed. A “Trifecta”—the mass was found to be a low-grade mast cell tumor and our surgeon was able to get a complete excision. Sammy was cured.

 

This was not the most complex case, nor was it a case that required combination therapy or a new or novel therapy. What this case represents, is the value of a good physical exam, the value of honest heart-felt communications, and the value of hope (along with a little bit of luck).

 

Every time we see Sammy—we are so thrilled that his mom said yes.

 

 

Dr. Gerald Post - 2013

The Veterinary Cancer Center