Friday September 15, 2017
KNOXVILLE, TN (Knoxville News Sentinel, by Jim Gaines) — When Lyla, a 6-year-old boxer, developed lumps in her throat and one on each hind leg, her owners Robin and Karen Hedden were afraid they knew what was wrong.When Lyla, a 6-year-old boxer, developed lumps in her throat and one on each hind leg, her owners Robin and Karen Hedden were afraid they knew what was wrong.
“My wife has had boxers in the past, and they are prone to cancer,” Robin Hedden said.
The Loudon residents took Lyla to her regular vet in Lenoir City, who diagnosed her with canine lymphoma and referred them to Knoxville’s Animal Emergency & Specialty Center at 10213 Kingston Pike.
Spare no expense
“They went over a very thorough treatment schedule, went over the options,” Hedden said. “We chose the longer-term treatment. We’re not going to spare any expense.”
Initial results were good. But after a couple of months, Lyla stopped responding to chemotherapy, said Jeff Phillips, oncologist at Animal Emergency & Specialty Center. In mid-July she wasn’t very frisky, and a knot under her chin signaled that her cancer had returned. Lyla came out of remission nine weeks into a 25-week course of treatment, Phillips said.
Before this year, Lyla’s options would have been very limited. But two new therapies have emerged, both available at Animal Emergency & Specialty Center. One is a vaccine which stimulates the immune system’s anti-cancer response, administered with a needle-free injector, Phillips said.
The other is Tanovea, a “completely novel type of chemotherapy,” he said. Neither is a cure, but the aim of both is to keep the disease in remission longer.
Tanovea is a second-line treatment for dogs such as Lyla who aren’t responding well to regular chemotherapy.
Lymphoma is one of the most common forms of cancer in dogs, Phillips said. Also called lymphosarcoma, it’s a disease of white blood cells which often starts in the lymph nodes, spleen or bone marrow.
“It’s 50 to 100 times more common in dogs than in humans,” Phillips said.
Humans with lymphoma have a variety of treatment options. But while the same treatments for many diseases can be used on dogs, that’s not the case with lymphoma, he said.
“Dogs until recently had none of those secondary options,” Phillips said.
Vaccine came out six months ago
The vaccine came out about 6 months ago, and Animal Emergency & Specialty Center quickly offered both it and Tanovea to its patients, Phillips said.
The effects of Tanovea are quickly apparent. Lyla had already improved when she came back for a second dose in early September. Licensed Technician Tammy Hilkert held Lyla gently on a table as the drug dripped in through an IV over 30 minutes.
“A lot of times they just go to sleep,” Hilkert said, keeping Lyla calm and still.
If practice treating Lyla will improve care for other dogs in the future, it’s worthwhile, Hedden said.
“We’re holding out all hopes it’ll work, but with the understanding there’s about a 90 percent chance it won’t,” he said. “If your dog is diagnosed with cancer, don’t give up. Don’t put your dog down. There are treatments available. Sometimes they work, sometimes they don’t; but it’s not the end of the road.”
Phillips said the clinic probably treats 150 to 175 cases of canine lymphoma per year.
“We do very well in the short term,” he said. Animals usually come in very sick, but can improve rapidly with treatment.
Only about 25, however, will likely be alive two years later. The new treatments still aren’t cures, but should lengthen and improve dogs’ lives, Phillips said.
But Tanovea and the vaccine aren’t cheap, he said. The vaccine, which requires four doses, costs patients $500 per dose. A full course of Tanovea is six doses, at $600 to $700 each.
Treatment may be stopped after one dose if Tanovea isn’t working, Phillips said. If it is working, treatments are given at three-week intervals.
Savannah, a 9-year-old beagle, was back for an ultrasound and checkup one week after her first Tanovea treatment. One morning in April, Savannah awoke lethargic, with no appetite, said her owner Susan Barner of Strawberry Plains. Barner knew that was unusual for the chubby, frisky dog.
“We’ve had her since she was six weeks old,” Barner said.
She took Savannah to her regular vet, Lori Smith at Tazewell Pike Animal Clinic, and within a couple days had a diagnosis of lymphoma.
Less than 24 hours later, Savannah got her first chemotherapy treatment at Animal Emergency & Specialty Center. She was in remission within a month, Barner said.
Beagles are predisposed to a type of lymphoma which usually responds well to therapy, Phillips said. But Savannah came out of remission after 15 weeks.
After talking with Phillips, Barner agreed to try Tanovea.
Before her first treatment with Tanovea, Savannah’s lymph nodes were enlarged, Phillips said. A week later they were back to normal.
Her spleen had been three to four times larger than normal, he said.
“It’s one of the hot spots where this cancer likes to grow,” Phillips said. After a week, an ultrasound showed only one black spot on a smaller spleen. Savannah’s liver still had many cancerous spots, but fewer than a week ago, he said.
“We’re very pleased with today’s outcome,” Barner said. “And her quality of life has not been affected at all with any of these treatments – she’s happy, she’s loving, she’s playful. That was my one concern, that her quality of life would be good.”
Savannah had already had a knee replacement, and three bouts with a fungal infection, Barner said.
“We lovingly refer to her as the billion-dollar beagle,” Barner said. “But actually, the chemotherapy has been very affordable.”
Animal Emergency & Specialty Center is one of the first veterinary oncology centers in the country, and the only one in the Knoxville area, to offer Tanovea, according to the company, which also has a Chattanooga location.
In January, the FDA gave conditional approval for injected use of rabacfosadine, under the trade name of Tanovea-CA1, for treatment of lymphoma in dogs. Its manufacturer is VetDC Inc.
Tanovea is one of a category of drugs developed in Eastern Europe, which only reached the United States after the fall of the Berlin Wall, Phillips said. A similar drug is on the market as a treatment for oral herpes in humans, but the canine version is unique, he said.
“Tanovea represents the result of 10-plus years of research,” Phillips said.
The drug’s most common side effects are decreased white blood cell count, diarrhea, vomiting, loss of appetite, weight loss, decreased activity and skin problems, according to the FDA. Owners are warned to be careful in handling and cleaning up after their dogs for five days after each treatment, since the animals’ immune systems will be weakened.
Dogs tend to tolerate chemotherapy better than humans do, according to Phillips – a week after treatment, when a person would probably still be in bed, Savannah seemed normal, he said.
A good life for a bit longer
A good life for a little longer is what Lyla’s owners are hoping for. The average lifespan for a boxer is only about a decade.
“We want to give Lyla a quality of life while she’s with us,” Hedden said. “She wants to play with everybody. She’s a very social dog. So whatever’s going to keep her happy while she’s with us, that’s what we’re going to do.”
This article was originally published by the Knoxville News Sentinel September 15, 2017. You can read the full article here.