How Precise Radiation Therapy is Helping Pets Beat Cancer

We had a dog with a tumor in its pituitary part of the brain at the base. It was so large it was causing him to walk in tight circles. He had three treatments and by day three, he was able to walk in a straight line.
Dr. Chad Johannes, Iowa State University

We all know the major give-and-takes of rural versus urban living: nature versus nightlife, open country roads versus congested freeways, and affordable living versus proximity to jobs.

Besides the negligible inconveniences, such as the occasional long drive to reach government offices or the nearest airport, the country lifestyle is ideal for many. But living at a distance from essential services does sometimes pose a problem when it comes to accessing specialized healthcare for yourself, and especially for your pets.

Stereotactic radiosurgery (SRS), a specific kind of radiotherapy (RT), is one such example. RT is now recognized as an essential element of an effective cancer care program throughout the world, as about half of all cancer patients can benefit from receiving the treatment in the management of their disease.

The beginnings of the therapy date back to the early 20th century, when scientists discovered that daily doses of radiation over several weeks greatly improved patients’ chances of being cured of cancer. But they quickly learned that exposure causes long term cell damage, meaning radiation could cause cancer as well as cure it.

Technology has been improving incrementally over the last 100 years, but it made a major breakthrough about 30 years ago thanks to advancements in radiation physics, computer technology, and 3D imaging. These developments enabled doctors to aim radiation at cancer cells with unprecedented precision. This update form of RT is known as SRS.

Radiotherapy for Pets

Veterinary medicine has also benefited from these advancements, improving treatments mainly for cats, dogs, and rats for all kinds of tumors, including those in the head and neck, oral melanomas, oral fibrosarcomas, nasal tumors, brain tumors and thyroid tumors.

As a result, RT is safer than ever before, has less of the debilitating side effects like fatigue and hair loss, and drastically reduces the number of necessary treatments from about 20 to only a couple. Compared to traditional surgery to remove tumors, SRS is also less risky and requires little to no recovery time—most patients can go about their normal routines following each treatment.

While it’s not suitable for every patient, it’s often a good option for solid tumors in areas that aren’t candidates for surgery, such as inoperable brain tumors or nasal tumors.

Outcomes can range from slowing down a cancer’s growth and prolonging life expectancy to even stopping cancer growth altogether and preventing it from returning. In either case, the quality of life of a sick pet can be increased, regardless of the ultimate outcome.

RT has been used to treat cancer in animals almost as long as it has been in humans. In fact, the first report of radiation therapy in an animal was published in 1905, just ten years after the discovery of x‐rays.

However, as is the case with other innovations in medicine, veterinary medicine has lagged a bit behind when it comes to availability of SRS because of the high price tag of the equipment (and the level of demand needed from pet owners to justify the investment.)

The Lag in Veterinary SRS Treatment

Availability of SRS treatment for animals in the U.S. has been mainly concentrated on the densely-populated coastlines. Florida and California have many of these treatment centers located within state lines—each tallying nine and 13, respectively—but there are 21 states between the coasts that don’t have a single one, as of 2020 data from the Veterinary Cancer Society.

The whole 12-state region of the Midwest has about the same number of veterinary radiation facilities (just a couple more) as California does, yet the Midwest is home to about 25 million more people and is spread out over 820,000 square miles, meaning there are significantly fewer SRS facilities per capita in the Midwest.

So, many individuals located in rural states seeking access to SRS treatment for their pets have faced the choice of either traveling a great distance to reach a facility—and making arrangements to stay the necessary amount of time to complete the required number of treatments—or saying goodbye to their pets too soon.

Fortunately, over the last ten-plus years, there has been a dramatic increase in the number of veterinary centers offering radiotherapy, “along with advances in imaging modalities and sophisticated computer‐aided radiation planning systems,” a survey found.

The Hixson-Lied Small Animal Hospital within Iowa State University’s College of Veterinary Medicine is one of the major players that has changed the game in the Midwest, opening their own SRS center in spring of 2019.

We talked to Dr. Chad Johannes, a practicing veterinarian and assistant professor within Iowa State’s College of Veterinary Medicine, to learn more.

Meet the Expert: Dr. Chad Johannes, Iowa State University

Dr. Teri Sue WrightDr. Chad Johannes holds a doctorate in veterinary medicine (DVM) from Kansas State University and completed residencies at University of Missouri-Columbia and North Carolina State University before joining Iowa State. Prior to his current role, Dr. Johannes worked for pharmaceutical company Pfizer and was involved in launching Palladia, the first FDA-approved cancer treatment drug for dogs.

Part of the reason Dr. Johannes was recruited to Iowa State five years ago was to help build the university’s oncology program. He was at the forefront of the process of getting the new radiation treatment facility up and running—a project that took about three years.

“In general, radiation treatments have been available primarily at universities for decades, but the technology has changed,” Dr. Johannes said. “As often is the case, we lag a little bit behind human medicine and just being able to afford that technology, and so that happened with stereotactic radiation.”

A Game Changer in Treating Animal Cancers the Midwest

Prior to the opening of Hixson-Lied Small Animal Hospital’s stereotactic radiation facility, Iowans had more limited options when it came to getting their pets cancer treatment.

“Depending on what technology you were looking for, we sometimes had to send clients to Colorado State for stereotactic,” Dr. Johannes said.

The drive to Colorado State University’s Flint Animal Cancer Center is about eight to 10 hours from Ames, Iowa. Clients typically have to leave their pet at the clinic to undergo the duration of the treatment, which takes about one to four weeks. This logistical challenge isn’t feasible for those that can’t afford to take time off work and pay for hotel accommodations on top of the expense of the treatment itself.

“It’s challenging to drive that distance and have your pet somewhere from anywhere to a week to four weeks depending on the radiation protocol, which just limited the options for a lot of clients,” Dr. Johannes said. “So, having the technology here to offer an additional treatment modality is a great option.”

Still, there are currently no radiation facilities in Nebraska, Iowa, and South Dakota. “Even Kansas City doesn’t have one,” Dr. Johannes added. “So, the closest ones we had were in Columbia, Missouri; Minneaplois, Minnesota; Madison, Wisconsin; and Colorado State University.”

Since opening last February, the clinic has treated cases from about seven states.

“We had a dog with a tumor in its pituitary part of the brain at the base. It was so large it was causing him to walk in tight circles. He had three treatments and by day three, he was able to walk in a straight line,” Dr. Johannes said. “He’s a year out now and is home and comfortable … many of his neurological signs have been alleviated. You can get a really significant improvement fairly quickly [with SRS].”

While there are many benefits of SRS, there are factors that pet-owners need to consider before moving forward that have to do with the kind of cancer the animal has, which determines whether or not the pet is a suitable candidate.

“Clients look at it from a quality of life perspective. Oftentimes, radiation is the best option for them and their pets because they don’t want that aggressive surgery,” Dr. Johannes said. “Sometimes we use a combination of surgery first to remove the bulk of the tumor and leave some cells behind and use radiation to go in and kind of clean up and treat those remaining cancer cells that are left.”

There is also the matter of the client’s ability to pay for treatment. Pricing varies depending on the client’s needs and the geographic location.

“You’re probably going to find a lot of regional variation. If you’re in Southern California, the price is much different than Iowa,” Dr. Johannes said. “Here the cost can range anywhere from $3,500 to $8,500 for the course of treatment depending on the tumor type, the number of treatments, how much imaging they need or don’t need to plan that.”

According to Dr. Johannes, the prices can be twice as much as that on the coast.

“It really depends on the region and kind of what technology [is being used], what treatment planning is involved and what the goals are,” he said. “So that’s why it’s a lot of conversation with clients talking about their goals and options so they can make the best decision for them.”

Increased Opportunities for Veterinary Technicians

Now, Dr. Johannes says, “more and more of our clients are wanting to do more advanced diagnostics and treatments on their pets with cancer.” And that means there are more opportunities for technicians in the field.

“The coasts are where many of the oncologists live and where many of the oncology facilities have been traditionally,” Dr. Johannes said. “But access for clients is growing and with those, the number of sites and the opportunities for veterinary technicians.”

The global veterinary oncology market size is expected to reach $369.2 million by 2026, a growth of 13.2 percent over the forecast period, according to some estimates. And North America is expected to lead the market growth mainly due to an increased focus on pet health, as well as innovation in drugs and treatment options.

“We’re taking better care of [our pets] with preventative medicine,” Dr. Johannes said. “If you and I live long enough and our pets live long enough—and we don’t develop heart disease or kidney disease—we’re probably going to develop some type of cancer, and that’s what we see in our pets.”

This growth in demand will need support from availability of qualified staff to operate the machinery. Technicians that specialize or medical oncology will be needed by SRS facilities in order to operate.

“They play a vital role with everything from client communication, patient care, giving updates, and administering the anesthesia,” Dr. Johannes said.

The need for veterinary technicians in the U.S. is expected to grow by 19 percent between 2018 and 2028—a rate much faster than average job growth, according to the Bureau of Labor Statistics.

“There’s this whole world of specialty medicine, oncology being part of it, that is definitely a growing field,” Dr. Johannes added. “There are more and more pharmaceuticals coming out that are directed toward cancer patients. Oncology is an added avenue for students to consider as they go through their training.”

Nina Chamlou (Writer)

Nina Chamlou is an avid writer and multi-media content creator from Portland, OR. She writes about aviation, travel, business, technology, and education. You can find her floating around the Pacific Northwest in diners and coffee shops, studying the locale from behind her MacBook.