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

Study Shows that Lymphoma in Dogs and Humans is Almost Identical

 

Comparative oncologists have been investigating the links between canine

and human cancers to develop effective treatments for both.  They believe dogs with spontaneously occurring cancers are especially relevant models for human cancers because dogs and people share the same water, breathe the same air, and in some households eat the same food. One of the most common subtypes of cancer, lymphoma, appears to be identical in both dogs and people.

In a recent wonderful study article published in Cancer Research (http://cancerres.aacrjournals.org/content/early/2013/06/19/0008-5472.CAN-12-3546.abstract), veterinary oncologists and researchers from North Carolina State University College of Veterinary Medicine, University of North Carolina, and Duke University show that diffuse large B-cell lymphoma is molecularly almost identical in dogs and people.

This NC State study is the first that uses molecular analysis by gene expression profiling (determining which genes are over or under expressed) and immunohistochemistry (staining a biopsy sample to determine the specific cell type) to compare canine lymphoma with human lymphoma. 

This study is very important as it clearly demonstrates the similarity between lymphoma in dogs and people. Because of this similarity—from what the cells look like under a microscope, to the expression pattern of the genes in the tumor—scientists can use lymphoma in dogs as a model to develop treatment for human lymphoma.

Animal Cancer Foundation Executive Board President Dr. David Levine applauds this study as “an incredibly important step in the development of a more representative animal model for diffuse large B-cell lymphoma in people. ACF believes that through the support of comparative oncology studies such as this, we will make significant strides in our work to better diagnose, treat and prevent cancer in both pets and people.”

 

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

Kobi's story

As promised, I’d like to share with you the story of Kobi, a tri-colored Collie that participated in one of our clinical trials in 2009. There have been many more stories just like his since then. My decision to share Kobi instead of a more recent patient was not without thought. Several months after Kobi’s passing, the Masilamani family was asked to share their story for the ACI (Animal Clinical Investigations) website as a success story. They were generous with their time, honesty and emotions by writing this wonderful story that walks you through from the time of Kobi’s diagnosis all the way until the end. While it would be wonderful if the last paragraph of Kobi’s story read, “He was cured and will be with us for another 5 years!”. Unfortunately, we know that is not how most of these stories end. The GREAT NEWS is that, as you read this, you will see that Kobi’s story doesn’t actually end in sadness. In fact, Kobi’s story hasn’t ended! The clinical trial that he participated in will likely result in approval of a new cancer drug for use in dogs! His story is still up on the website for all to read and now you are getting to meet Kobi! The more you share his story or repost, the more his story gets to continue… In my next blog, you will meet Frida, an amazing dog with unbelievable owners that flew her from their home in Cancun, Mexico all the way to us in Connecticut to participate in a clinical trial. Frida’s story has unlikely (happy) ending to her clinical trial journey and the start of a new chapter in her life and you won’t want to miss it!

This is the Story of Kobi (as told by the Masilamani Family) http://www.animalci.com/for-pet-owners/success-stories

Kobi was a 3-year old, tri-colored collie I got from a rescue. He was our first family dog, and a wonderful addition to our family. He stayed true to the collie temperament and we had the most memorable 7 years with Kobi. A few days before Thanksgiving 2009, I had noticed a swelling on his mouth, and had taken him to get it checked out. After a week of antibiotics the swelling had not gone down, so the veterinarian ran a test. He soon informed me it was cancer. Kobi was diagnosed with a mast cell tumor, and was given 3 months to live. I did not have many options; it was either treatment in NY, which would cost thousands of dollars, or enjoy him for the next few months and provide him with a life of love and comfort. Although it was a hard decision, I chose not to seek medical treatment, knowing that any treatment would only prolong the inevitable. That Thanksgiving was a very difficult time, knowing he wouldn’t be with us the next year. That said, we were grateful for the time.

A week later I received a call from my vet, telling me about a clinical trial that was testing a new treatment for cancer for dogs. They were curious as to whether I would be willing to talk to the folks at the oncology and hematology center (The VCC) in Norwalk, to see if I would want to participate. As soon as I was off the phone with my vet, I called the office in Norwalk and set up an appointment to meet with their team of vets and staff. While I know that no cure for cancer has been found, I wanted to know if this trial would help to understand and treat this illness, and maybe someday help to eradicate cancer from the world.

After meeting with the folks at The VCC, I was happy to enroll Kobi into this trial. As much as Kobi was doing his part in the treatment, our family was also involved in documenting his progress through the series of treatments for the next 4 months. These four months were difficult for all of us, including some of Kobi’s reactions to the medication, but through the care provided by The VCC and love from everyone involved we kept on, knowing our experience would someday help toward the cure for cancer for dogs.

After the 4-month trial, Kobi’s cancer “burden” was greatly reduced, and I knew that this trial had extended Kobi’s life. For the next 18 months, Kobi lived a full and fun life; we cherished every moment we had with him. Sadly one weekend, it came to a sudden end. Just a day before, he was out in the backyard running around with me and my kids, and the next morning, he was all worn-out. He wouldn’t eat and just laid down breathing heavily. The next day I took him to the vet’s office and they did an x-ray on his stomach, which showed a large gray mass. Knowing his previous condition, the veterinarian was sure it was cancer. He gave me some medication to ease the pain that Kobi could be experiencing, and told me it was a matter of time before the end. That night, as Kobi lay on his favorite bed, each of us prayed with him and said our goodbyes. I pulled a sleeping bag next to him, and prepared to spend the night with him. I knew he was not going to make it through the night – his breathing got shallower as the night progressed, and around 2am I could not hear his breathing anymore. I reached over to him, resting my ear to his chest, and I knew he had passed on.

We had Kobi cremated, and a print of his paw taken in clay. My family and I are ever so grateful for the opportunity we were given through this clinical trial, and for giving us 18 more precious months with Kobi. Kobi is not with us any longer, but we know that through his life not only did he give us love, but a chance that someday other dogs may not have to go through what he did.

- The Masilamani family

The Influence of Dogs on Human Development



A recent archaeological dig found what is believed to be a dog’s head carbon dated over thirty-one thousand years ago. Whether our relationship with dogs goes back twelve thousand years or a hundred thousand years the fact remains that our relationship with “man’s best friend” goes back further than any other animal.



The debate about how dogs became domesticated is still widely debated. Most scientists and researchers believe that cave men would not have had the resources needed to breed wolves’ generation after generation culminating in today’s domesticated dog. These early humans would have been too busy hunting, gathering and would need to have pooled all of their resources just to survive.

The fact remains that there are very few animals that are both social hunters, carnivores, and hunt by the light of day. This combination of behaviors could have created a natural teamwork between man and wolf (the predecessor of domesticated dogs).



The domestication of the wolf likely fundamentally changed human life style by allowing us to be better hunters and thereby providing more food. This would enable the survival of more human offspring and helped to ensure our success as a species. There is also the theory that the domestication of the dog led to the creation of agriculture by helping early humans guard and protect their flocks as well as their crops. Some people even postulate that without dogs, man would still be hunter-gatherers and that civilization as we currently know it would not have been possible.

 

Recent studies by cognitive behaviorists showing that dogs are the only other species that responds to us pointing to an object – something that we take for granted with our dogs. These studies show that even highly intelligent species such as chimpanzees are not capable of understanding this type of gesture.  This does not imply that dogs are (arguably) smarter than most species, but it does show how uniquely suited they are for human companionship.

 

Dogs not only respond to finger pointing, but also are remarkably good at understanding our eye movements. Humans are one of the only species that have sclera (whites of the eye) that is visible. This is believed to be an adaptation to enhance human communication using nothing but our eyes. The dark coloration around most other animals’ eyes suggests an adaptation to camouflage gaze direction so that predators could not predict movements by watching their prey’s eye movements.

  

The truly fascinating aspect is that even though dogs do not use either of these two characteristics to communicate with each other, they have learned to watch for this type of input from people. Dogs are also very good at reading our emotions and body language, making them the undisputed winners of the title “man’s best friend”.

 

 David Duchemin

Chief Operating Officer, and Practice Co-Owner of

The Veterinary Cancer Center

Co-Founder, and Treasurer of

The Riedel & Cody Fund